Showing posts with label Texts. Show all posts
Showing posts with label Texts. Show all posts

Wednesday, December 8, 2010

Contrail Clouds

Contrails (short for "condensation trails") or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets. If the air is cold enough, this trail will comprise tiny ice crystals.

The wingtip vortices which trail from the wingtips and wing flaps of aircraft are sometimes partly visible due to condensation in the cores of the vortices. Each vortex is a mass of spinning air and the air pressure at the centre of the vortex is very low. These wingtip vortices are not the same as contrails.




Depending on atmospheric conditions, contrails may be visible for only a few seconds or minutes, or may persist for many hours which may affect climate.


Condensation from engine exhaust

The main byproducts of hydrocarbon fuel combustion are carbon dioxide and water vapor. At high altitudes this water vapour emerges into a cold environment, and the local increase in water vapor can push the water content of the air past saturation point. The vapour then condenses into tiny water droplets and/or deposits into ice. These millions of tiny water droplets and/or ice crystals form the vapour trail or contrails. The vapor's need to condense accounts for the contrail forming some way behind the aircraft's engines. At high altitudes, supercooled water vapor requires a trigger to encourage deposition or condensation. The exhaust particles in the aircraft's exhaust act as this trigger, causing the trapped vapor to rapidly turn to ice crystals. Exhaust vapour trails or contrails usually occur above 8000 meters (26,000 feet), and only if the temperature there is below -40°C (-40°F).

MODIS tracking of contrails generated by air traffic over the southeastern United States on January 29, 2004.

From the photograph you can imagine how many air traffic in southern United States. There'd be so many flight in a day.

Wednesday, December 1, 2010

Mushroom Clouds

A mushroom cloud is a distinctive pyrocumulus mushroom-shaped cloud of condensed water vapor or debris resulting from a very large explosion. They are most commonly associated with nuclear explosions, but any sufficiently large blast will produce the same sort of effect. They can be caused by powerful conventional weapons like the GBU-43/B Massive Ordnance Air Blast bomb. Volcano eruptions and impact events can produce natural mushroom clouds.


Mushroom clouds form as a result of the sudden formation of a large mass of hot, low-density gases near the ground creating a Rayleigh–Taylor instability. The mass of gas rises rapidly, resulting in turbulent vortices curling downward around its edges, forming a vortex ring and drawing up a column of additional smoke and debris in the center to form its "stem". The mass of gas eventually reaches an altitude where it is no longer of lower density than the surrounding air and disperses, the debris drawn upward from the ground scattering and drifting back down.


Origin of the term

Although the term itself appears to have been coined at the start of the 1950s, mushroom clouds generated by explosions were being described before the atomic era. For instance, The Times published a report on 1 October 1937 of a Japanese attack on Shanghai in China which generated "a great mushroom of smoke". During World War II, descriptions of mushroom clouds were relatively common.



The atomic bomb cloud over Nagasaki, Japan was described in The Times of London of 13 August 1945 as a "huge mushroom of smoke and dust." On 9 September 1945, The New York Times published an eyewitness account of the Nagasaki bombing, written by William L. Laurence, the official newspaper correspondent of the Manhattan Project, who accompanied one of the three aircraft that made the bombing run. He wrote of the bomb producing a "pillar of purple fire", out of the top of which came "a giant mushroom that increased the height of the pillar to a total of 45,000 feet."



Later in 1946, the Operation Crossroads nuclear bomb tests were described as having a "cauliflower" cloud, but a reporter present also spoke of "the mushroom, now the common symbol of the atomic age." Mushrooms have traditionally been associated both with life and death, food and poison, making them a more powerful symbolic connection than, say, the "cauliflower" cloud.


Physics

Inside a mushroom cloud: cooler air is drawn into the rising toroidal fireball, which itself cools into the familiar cloud appearance.

Mushroom clouds are formed by many sorts of large explosions under earth gravity, though they are best known for their appearance after nuclear detonations. In space the explosion would be somewhat spherical. Nuclear weapons are usually detonated above the ground (not upon impact, because most of the energy would be dispelled into the ground) in order to maximize the effect of their spherical expanding fireball and the blast wave. After immediate detonation, the fireball itself begins to rise into the air, acting on the same principle as a hot-air balloon.

One way to analyze the motion, once the hot gas has cleared the ground sufficiently, is as a 'spherical cap bubble', as this gives agreement between the rate of rise and observed diameter.

While it rises, air is drawn into it and upwards (similar to the updraft of a chimney), producing strong air currents known as "afterwinds", while inside the head of the cloud the hot gases rotate in a toroidal shape. When the detonation itself is low enough, these afterwinds will draw in dirt and debris from the ground below to form the stem of the mushroom cloud.

After the mass of hot gases reaches the equilibrium level, the ascent stops and the cloud starts spreading to the characteristic mushroom shape.

Wednesday, November 10, 2010

4 Fruits That Can Whiten Your Teeth

Below these were the most useful fruits used to whiten the teeth. Could you imagine the small cute strawberries, wonderful apples, crunchy carrots and the sour lemon or lime juice can make your smile gettin brighter? Now, you don't have to go to dentist for making your smile looks great, these fruits can help you get your beautiful smile back.


1. Strawberries

It was Strawberries are a natural food to whiten the teeth. Strawberries contained malic acid that act as a substance that can erode and remove stains on tooth surfaces.


2. Apples

Apples contain two useful in helping to whiten teeth. The first benefit, the process of biting hard and crunchy apples can tarnish of dental plaque that can change the color of your teeth become whiter. Also, biting the apple also stimulates production of saliva which can naturally fight bacteria in the mouth that change the color of teeth. The second benefit, apples contain malic acid which act as natural ingredients to remove stains on tooth surfaces.


3. Carrots

Carrots can also function as a natural tooth whitener. Carrots also contain that can remove dental plaque that hard during the process of mastication.


4. Lemon or Lime Juice

Lemon juice can also be used to whiten teeth. Lemon juice can be combined with the salt and baking soda made like pasta mixture. Then rub the mixture on the teeth for 10 to 15 minutes. Do this treatment twice a week.

Always rinse and brush your teeth properly after using lemon juice on teeth. High citric acid content in lemons can cause tooth enamel fragility.

Thursday, September 16, 2010

The Largest Snake Ever Found, Over 50 Feet

About Snakes:

Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with many more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads with their highly mobile jaws. To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional lung. Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca.

worldsbiggest

Kids react to the video:


Friday, September 10, 2010

40 Interesting Facts

1. California has issued at least 6 drivers licenses to people named Jesus Christ.

2. Kangaroos can not walk backwards.

3. 'Jedi' is an official religion, with over 70,000 followers, in Australia.

4. According to a recent survey, more than half of British adults have had sex in a public place!

5. Most alcoholic beverages contain all 13 minerals necessary to sustain human life.

6. Nachos is the food most craved by pregnant women.

7. Each year, 24,000 Americans are bitten by rats!

8. Most dreams last only 5 to 20 minutes.

9. The hair of an adult man or woman can stretch 25 percent of its length without breaking.

10. On average, the life span of an American dollar bill is eighteen months.

11. Non-dairy creamer is flammable.

12. The first domain name ever registered was Symbolics.com.

13. Americans collectively eat one hundred pounds of chocolate every second.

14. U.S. President Calvin Coolidge liked to eat breakfast while having his head rubbed with Vaseline.

15. When a giraffe's baby is born it falls from a height of six feet, normally without being hurt.

16. Venus is the only planet that rotates clockwise.

17. The creator of the NIKE Swoosh symbol was paid only $35 for the design.

18. How does a shark find fish? It can hear their hearts beating.

19. Penguins can convert salt water into fresh water.

20. In ten minutes, a hurricane releases more energy than all the world's nuclear weapons combined!

21. The IRS employees tax manual has instructions for collecting taxes after a nuclear war.

22. During WWII, because a lot of players were called to duty, the Pittsburgh Steelers and Philadelphia Eagles combined to become The Steagles.

23. Nearly 22,000 checks will be deducted from the wrong account over the next hour.

24. More than 50% of the people in the world have never made or received a telephone call.

25. There are more fatal car accidents in July than any other month.

26. There are more bacteria in your mouth than there are people in the world.

27. More than 2 million documents will be lost by the IRS this year.

28. Bats always turn left when exiting a cave.

29. Washington, D.C. has one lawyer for every 19 residents!

30. Avocados have more protein than any other fruit.

31. The average car produces a pound of pollution every 25 miles!

32. Cranberries are sorted for ripeness by bouncing them; a fully ripened cranberry can be dribbled like a basketball.

33. In 1980, a Las Vegas hospital suspended workers for betting on when patients would die!

34. The most powerful electric eel is found in the rivers of Brazil, Columbia, Venezuela, and Peru, and produces a shock of 400-650 volts.

35. If the population of China walked past you in single file, the line would never end because of the rate of reproduction.

36. Antarctica is the only land on our planet that is not owned by any country.

37. In India, people are legally allowed to marry a dog!

38. You are more likely to get attacked by a cow than a shark.

39. Half of all identity thieves are either relatives, friends, or neighbors of their victims.

40. One in three male motorists picks their nose while driving.

source: dave’s daily

Wednesday, September 8, 2010

A Special Love For An Extraordinary Person

On December 12th, a 93-year-old Tianjinese was selected as one of the 20 candidates for the “People Who Moved China” 2005 award. When his name, photo and activities were broadcast with those of Yuan Longping, Liu Xiang and Ren Changxia on CCTV, the whole country was moved —— it was very difficult for general public to connect the 350,000 RMB donation with an old and thin person who lay paralyzed in bed.


‘An old man, a pedicab, 350,000 RBM donation, 300 poor students……’ when all these words are connected together, the difficulty, misunderstanding, persistence and charitable love of an old man’s life was unrolled before the eyes of general public.


This generous old man was Bai Fangli.


In Daoism, it said that a great brightness seems like darkness; a great square has no corners; a great ability takes a long time to perfect; a great sound is hard to hear; a great form has no shape. It also said that a great perfection seems flawed; a great fullness seems empty; a great straightness seems crooked; a great skill seems clumsy and a great eloquence seems stammering.


Bai Fangli led a simple lifestyle. He never took pride in honor; never explained away misunderstandings and never showed arrogance before admiration. Maybe, in the eyes of ordinary people, what he demonstrated could be called ——— great love.



A turning point: at 74 years old, he started on another road.

“Money is needed for students to go to school, money is needed for schools to maintain teachers and money is needed to rebuild old classrooms……”



While Bai’s food simply consisted of a fried bun with green Chinese onion and soy sauce along with a bowl of wontons, he began to aid education in 1987, when he was 74 years old. In that year, Bai came back to his hometown in Changxia County, Hebei Province as he prepared to retire and say goodbye to his pedicab. A group of children working in the field aroused his attention. Later, he learned that these children did not go to school because they lacked the financial resources rather than that they were naughty. The school was unable to collect tuition, and without money, it was unable to maintain the teachers and without teachers, how could the students learn? “Money is needed for students to go to school, money is needed for schools to maintain teachers and money is needed to rebuild old classrooms……” These thoughts keps the old man awake at night. He remembered that he, himself, left Tianjin because of poverty; and now decades later, his hometown was still poor. How could this next generation change their lives without education? Do we keep watching today’s children remain illiterates like their forefathers?


As soon as he returned to Tianjin, Bai went back to work. He rode his pedicab once more and donated his pension of 5000 RMB to aid education. At the age of 74 years old, he began pedaling another road.



Stubbornness: love, frustration was carried by the little pedicab.

“let him to do it If only he feels happy. If he does not like it, he will return to a comfortable life.”
“You are so old and you have sons and daughters, why don’t you stay at home to enjoy a relaxing life since you have worked so hard and not had an easy life until now.” His children try to persuade him.


“I have strength to do it, and it makes me happy to earn money for the students by driving my pedicab.” Bai was continued to be stubborn, even in his old age.


At that time, Bai went out in the early morning and wouldn’t return until after 11 pm, summer and winter. Daily, his children worried about him and waited for him at the door. They wouldn’t rest until they saw their old father return back. However, no matter how they tried to persuad him, the father turned a deaf ear to them. Sometimes, they tried to stop him, Bai persisted in his decision. In the end, the family gave up: “let him to do it If only he feels happy. If he does not like it, he will return to a comfortable life.” Therefore, by driving a pedicab, the old man earned money to make one donation after another to organizations like the Reward Fund for Teachers in Tianjin Primary and Middle High School, China Youth Development Fund and Children’s Palace in Hebei District, Tianjin.



A Record: Donating money earned with sweat and toil by driving a pedicab.

“The money donated by Grandpa Bai was full of sweat and toil, and we cannot let him down”

On September 1st, the government rewarded Bai Fangli the plaque of “Model Citizen of Supporting Education” in Daguangting Township, Chuangxian County, Hebei Province.


Later on, to increase his effort to assist students in need, Bai moved to a simple room near the Eastern Tianjin Railway Station. At that time, he waited for clients 24 hours a day, ate simple food and wore discarded second-hand clothes he found. His donations were sent to poor students in Hongguang Middle High School, Nankai University, Tianjin University.


When he first started donating funds, Bai did not ask for receipts. In his opinion, the receipts were useless if his donations were necessary. However, the beneficiary organizations recorded his donations clearly. “The money donated by Grandpa Bai was full of sweat and toil, and we can not let him down.” For this, the recipient organizations paid great importance to funds received from Bai. Besides recording the use of the donations, they also held a ceremony to distribute Bai’s donations. During the ceremony, Bai was able to see the students accept his donation and heard them report on their studies. This gave Bai great comfort, especially when he heard the school say: “you must not waste your grandpa Bai’s money, which was earned by driving pedicab. But if you study well and grow up healthily, please don’t worry about money, your grandpa will earn money for your tuition and other school fees.”


Bai drove his pedicab for 56 years and sponsored education for 18 years. During this time, the pedicab, his comrade in arms, accompanied him through rains and winds. Now, please take a rest when you tired and let the pedicab also take a rest for a while.



Frustration: Persistence, there are so many students waiting for help.

“he is a common person, he also has concerns and at times confusion. ”


Bai had adhered to his conviction for decades, and what is the power that supported him to overcome difficulties, misunderstandings and disagreements? Yang Junye, the head of Tianjin Association of self-employed individuals said that Bai was simple and noble person; he had no selfish reason for aiding education. Yang Junyu was 20 years younger than Bai, but he was his “old leader” and “friend of different generations”. On the long journey of supporting and aiding education, Bai would tell Yang what confused him. “Bai is a stubborn person; he will stick to his commitments once he has made decision. But he is also a common person; he also has concerns and at times confusion.”

In 1998, to follow municipal policy, Bai stopped his education support company, dismissed the workers, sold out the company’s properties. He then donated the 20,000 RMB to several schools. “One day, I heard a person calling me at the eastern railway station; I turned around and found it was a thin old man. After a moment, I recognized it was Bai. He was so thin that his shape had changed a lot. He told me: ‘the company is closed, but I am not willing to go. I had not eaten for several days and I can not support the students. I don’t want to live. ” What Bai said surprised Yang deeply. He took him to his home and consoled him: “it is right for you to aid the education and it is also right for you to follow the municipal policy. I support you, but you must open your mind. I will find reporters to report what you did and so everyone will learn from you. You should promise me that you will live to be 100 years old.” Bai opened his mind and found the hope ——— there are so many students still waiting for help. He determined to be the model for others follow. How could he stop at that time?



Concern: Supporting Education, the road to be walked on.

“As I recovered, I will continue to support education.”

Every time when Bai delivered a donation to Hongguang Middle High School, the students would wished he would stay longer.


Reports about Bai’s deeds in supporting education were growing. He won many rewards and attended more and more gatherings…… however, since there was no aid for Education Company, his road to support education became more difficult. The company had closed, but he continued to stay in the simple room and accumulated his money cent by cent. As the cents cumulated to hundred RMB, he would wrap them in strings and deliver them to the schools. At that time, he did not know how long he manages to keep doing this. In 2000, he fell from his pedicab and injured his arm. However, he did not go to the hospital but instead continued to drive pedicab to earn money. In the end, his daughter persuaded and accompanied him to check out his arm at hospital. It turned out he wasn’t supposed to move his arm due to a bone fracture.


It was then impossible for him to drive the pedicab because of his physical condition ——— and he had to stop his work to aid education. However, he was missed the students and thought: “I will continue this work when I am healed.”



Eternity: Love will continue promoted by the model.

“you have led a hard life, and we should return the service to you since you are so old.”

His aid of education deeds attracted many students to visit him.


During his period of supporting education, Bai also made donations to Tianjian Resthome. When festivals or holidays came, he would send the resthome his hundred RMB donation to console the old people. In 2000, he at last said goodbye to his pedicab and went to the home for rest. The Tianjin Resthome arranged a high grade room for him and appointed special staff to take care of him. People said: “you have led a hard life, and now you are so old that we must return the service to you. It is also convenient for students to see you.”


The condition in resthome was good and the staff was very kind, but Bai found it difficult to have others serve him. He always telling the staff: “you take a rest, I can look after myself.” He thought that he was troubling others———“I have not done anything, and the government paid me attention and brought me here, now I trouble you to take care of me. I might as well go home.” So, with his persistence, he moved to the house of his daughter, Bai Jinfeng.


After going home, he did not stop working; he found reports about him in various media and arranged them into a handbook. When students came to see him, he would show it to them and educate them. He told them to study well and use their talents in future to support their country. His words were simple, but like seeds, they were planted in the hearts of the students. By now, many students supported by him were supporting other poor students.


Sunday, August 22, 2010

The Myths of Vegetarianism

The Myths of Vegetarianism was originally published in the Townsend Letter for Doctors & Patients, July 2000 (and was revised in 2002). Whilst I agree with Byrnes on a few of his points, and applaud him for bringing some pertinent issues to the attention of vegetarians, I believe that much of what he has written is misleading and many of his arguments are invalid.

I KNOW VEGETARIANS who seem distinctly unhealthy: pale faced, weak and unable to concentrate. I also know meat-eaters that are equally unhealthy: red-faced, gasping for air and with high cholesterol. Stereotypes for sure! There are also both vegetarians and meat-eaters who are very healthy — like Byrnes himself who looks the picture of health! That said, statistically, vegetarians are healthier than meat-eaters and there is, contrary to what Byrnes tells us, much supporting evidence for this.

Of course there will be "several authorities" that question this data… there are authorities who question global warming, whether BSE could affect humans, and the wisdom of farming without pesticides and herbicides. Experts have different opinions and anyone who has been in the academic world will be aware that, after degree level, scientific knowledge is often conflicting and open to much interpretation. These "several authorities" have probably been "ignored" (presumably by vegetarians) because most vegetarians are primarily making an ethical stand rather than merely choosing a more healthy lifestyle (unless they have been scared off a meat-based diet by BSE!).

Byrnes' article is very useful to the vegetarian community because it reiterates the fact that just because a diet is vegetarian doesn't automatically mean it healthy — an assumption that has seen many a healthy omnivore turn into an unhealthy vegetarian. Byrnes does us all a favour by bringing this important issue to light. However, in the process, it would seem that he has been overzealous in his dismissal of vegetarianism, to the point whereby he has presented some arguments that make no sense, others that are contradictory, and selected research that that in no way is representative of the pervading opinion on these matters which is based on the total research done in this area. This, of course, is his prerogative, but in doing so he actually ends up diluting the pertinence of his message by trying to make the scope of his argument a little too broad—the "myths" a little too numerous. This is a shame as it is essential to be quite mindful when eating a vegetarian diet to make sure that we get all the nutrients that we need for our particular body type. By dismissing everything about vegetarianism out of hand, Byrnes becomes as imbalanced as the "vege-fanatics" he derides.

I shall go through his article myth by myth, giving what I believe is a much more balanced point of view. Some of his myths I actually agree with and others I am not able to comment upon at greater length as I am not up on the current scientific research.

Myth #1: Meat consumption contributes to famine and depletes the Earth's natural resources.

The first myth certainly exposes Byrnes' biasness. I am surprised that he would put this as his first myth as it is certainly his weakest point. Meat consumption today certainly does contribute to both famine and the depletion of Earth's natural resources.

Byrnes' arguments here do not make a lot of sense. First of all, if Earth's dry land is suitable for grazing animals, it is entirely possible to make it suitable for farming (unless it is extremely rocky and / or mountainous); methods and technologies do exist that can enrich thin soils and produce fantastic yields in these sorts of dry areas. Stating that this land is "currently being put to good use" seems rather an odd statement when one considers how destructive grazing animals are at converting scrubland to desert. Contrary to what Byrnes' believes, you cannot graze a modern cattle herd on thin scrubland or desert. They need a constant and abundant supply of rich grasses, fattening feeds and huge amounts of water. Herds end up stripping away the grass protection for the topsoil and lowering the water tables, a combination that creates thousands of square miles of empty desert every year. What is more they create a significant proportion of greenhouse gases. The cattle are just moved on to put another area of land "to good use", whilst the deserts never ever recover.

Byrnes then quotes from Breeds of Livestock (University of Oklahoma, Department of Animal Science) which over-simplifies the contribution of agricultural animals and has an obvious bias! Whilst it is true that animals have made a major contribution to human welfare, it is simply not true that they provide a "renewable resource". Sure herds are renewable in the breeding sense, but the effects of those herds on the land is certainly anything but renewable. And manure produced by these animals is in such large quantities that it is now poisoning the water supplies with nitrates. (And burning this manure is hardly the solution for the large herds that now dominate the modern meat industry!)

Breeds of Livestock then goes on to state that "over two-thirds" of the feed fed to animals consists of substances that are either undesirable or completely unsuitable for human food, and uses this fact to dismiss the argument that vegetable matter can more efficiently be fed directly to humans rather than to cattle which in turn feed humans. This is illogical: two-thirds of the feed fed to animals is precisely that which is undesirable to humans because it is being grown specifically for animals! Otherwise the land would be used to grow crops suited to human consumption.

Byrnes then states that widespread poverty is responsible for lack of food, not the ability of the world to product it. But he does not question why people are so poor in the first place and why food is so expensive. In many Third World countries, the people are starving whilst these countries are exporting expensive meat products. Had they been growing vegetables instead, the cost of the food would be significantly less and exporting less of an attractive money-spinner. And of course the Population Reference Bureau would not attribute world hunger to meat-eating when they are, according to their own information, "funded by government contracts, foundation grants, individual and corporate contributions… " Considering that the US government strongly supports the meat industry, and that the meat industry is infinity more wealthy than those who advocate vegetarianism and therefore is much more likely to be contributing to the Population Reference Bureau, it is hardly surprising that they do not denounce the meat industry in their reports!

Then something quite astonishing happens. Byrnes, an academic, quotes an opinion posted on an anti-animal rights website forum as justification that food availability would actually decrease if we all became vegetarians. His concern at a decrease in food production is a little misplaced because, in preceding paragraph, he states that "at the present time, there is more than enough food grown in the world to feed all the people on the planet". But a potential decrease in food production is only one opinion from a site that is supporting a very profitable industry, and not widely held. It is much more likely that food production and availability would be increased as grain used to feed animals is either used directly or upgraded for human use, and land used for cattle grazing is turned into arable production. (Three hectares can produce either one tonne of beef, or 50 - 100 tonnes of grains, pluses and vegetables.) This increase in availability (even if overall production is decreased — which is unlikely) would drive down prices. Less land would be needed to feed the world and so land would not be so attractive to large producers allowing local farmers to grow their own crops. Rainforest would be less at risk, water tables given a chance to recover, desertification would be massively reduced and the methane production would plummet.

It is laughable to state that it is basically animal husbandry that is keeping the world from becoming a crop monoculture! This is happening anyway, in the meat industry as well, as food production reaches ever larger scales. In fact, it could be argued that if less monoculture crops were grown for animals, which are given a very basic diet, and more for humans, there would be increased demand for variation. As for the heavy use of fertilizers that would be needed for crops, Byrnes forgets that he has argued previously that there would actually be a drop in overall vegetable food production. In fact, as crops grown for animal feed have less stringent pesticide residue requirements, the overall pesticide use could be substantially reduced. And there is little point bemoaning the fact that one ton of fertiliser requires 10 tons of crude oil to produce when at the present moment huge amounts of grain crops need to be grown to feed animals which then feed people, a hugely inefficient use of crude oil. And what about the poisons used to kill parasites on animals, the steroids used to make them grow faster and the antibiotics used to cover up their ill health?

In the next paragraph, Bynres quotes a British organic dairy farmer who is obviously no impartial observer. Mark Purdey erroneously points out that a predominantly vegetable farming system would produce soil erosion (but forgets to add that animal farming produces a lot more erosion for the equivalent calorific production), agrichemical use (but does not add that, as explained above, pesticide use is likely to be reduced), cash cropping (meat is far the biggest cash crop around), prairie-scapes (like the sort used to graze animals?) and ill health (spoken just like someone in the meat industry). Mark Purdey understandably has a rose-tinted view of meat production around the world.

It is very easy to list the evils of large scale arable monoculture. Most vegetarians oppose this sort of farming as well. However, when one compares the effects of large scale crop monoculture with large scale meat production, the former "wins" hands down in terms of environmental impact. Aware of this, Byrnes resorts to the absurd comparison between small scale animal/mixed farming and large scale arable monoculture production. Clearly, the latter has a greater environmental impact. He fails to mention that the arguments in favour of mixed crop farming are even more applicable to mixed vegetable crop farming as they are to vegetable/animal mixed farming. It is all very well for Purdey, a small scale farmer, to critisize intensive agribusiness and favour the resurrection of "the old traditional extensive system" but he fails to outline exactly how this system could cope with the massive demand for food today. The fact is, that for the foreseeable future and until farmers become better educated in ecological farming practices, large scale intensive farming is going to pick up the load whether we are meat-eaters or vegetarians, and large scale vegetable farming is certainly environmentally preferable to large scale meat production.

After quoting Purdey, Byrnes finishes off this "myth" with the remarkable assertion that "It does not appear, then, that livestock farming, when properly practised, damages the environment." This is a little strange when one considers that Purdey, in the sections quoted, does not mention or give evidence for this conclusion at all. Byrnes has drawn this conclusion out of thin air. He then asserts that world vegetarianism could not be supplied by agriculture (a very curious statement considering that already enough vegetable matter is produced to feed the world) and that trying to do so would not be ecologically wise — as if supplying the world with meat is a better solution! These are completely illogical arguments.

More recently in 2007, The United Nations Food and Agriculture Organization (FAO) examined the impact of the livestock industry on global warming, concluding that this industry accounts for 18% of all greenhouse gas emissions, which is significantly higher than the 13.5% produced by all world transportation (cars, planes, trains etc.). In fact, a single cow can produce as much as 500 litres of methane a day, a gas 23 times more causative to global warming than carbon dioxide. So although changing to energy-saving light-bulbs or using cars only for essential journeys is important and may make us feel green, unless we change to a vegetarian diet our actions will not be enough to stop the destruction of planet Earth.

Myth #2: Vitamin B12 can be obtained from plant sources.

I agree with Byrnes on this one: it is essential for all vegans to include a B12 food supplement in their diets (these supplements are made from bacterial cultures and so can be taken by vegans). There is some evidence that certain foods like Klamath Blue Green Algae contain available (non-analogue) B12, and that this vitamin can be manufactured by intestinal flora and that it might be in the soil residues, but it is dangerous to rely on these sources for such an essential vitamin (although many people have and with fair results). The risks are too great not to supplement. Byrnes last statement that vegans a few decades ago would have died as they did not have supplements or fortified foods is not true as veganism is not a modern invention!

Myth #3: Our needs for vitamin D can be met by sunlight.

I also agree with Byrnes on this, and it is important for vegans to mindfully include quantities of alfalfa, sunflower seeds and avocados in their diets. Supplementation is also an option. That said, short periods of exposure to sunlight (15 minutes a day or more) are enough to prevent deficiency, although those with darker skins need more.

Myth #4: The body's needs for vitamin A can be entirely obtained from plant foods.

Once again, supplementing vitamin A is no problem, although it has to be said that vitamin A deficiency is quite rare in vegans who have adequate beta-carotene. Byrnes does point out that "infants and people with hypothyroidism, gall balder problems and diabetes have difficulty making the conversion from beta-carotene to vitamin A" which is useful for vegans to know. But this is hardly justification to promote an animal based diet when supplementation is so easily available.

Myth #5: Meat-eating causes osteoporosis, kidney disease, heart disease and cancer.

Here, Byrnes returns to grinding his axe. Clearly, there is little point comparing the modern Western meat-rich diet with that of other cultures. The meat is entirely different and is often eaten raw. The Masai, for example, are remarkably healthy primarily on a diet of raw blood and raw milk which are unaffected by cooking or the toxins associated with modern cattle farming, although it should be pointed out that the average Masai lifespan is much shorter than that in the West, making comparisons more difficult. The Innuits also eat large quantities of animal fat, but again they eat it raw. Eating meat in its raw state (although not recommended in the West because of parasites and infections) can sometimes be healthier, but as we will see, this does not exclude these cultures from problems associated with a meat-based diet.

Osteoporosis: It is not true that meat consumption has no impact on bone density. Recently, there was an interesting article in New Scientist (15 Dec 2001 / No. 2321) entitled Hard Cheese by Douglas Fox which gives a detailed overview of this the effect of an acid diet on osteoporosis. Accoridng to the biggest and best study to date, the Study of Osteoporotic Fractures (SOF)—which has followed nearly 10,000 elderly women since 1986—more than half of all hip fractures are actually due to dietary acid load. According to Uriel Barzel, an endocrinologist at the Albert Einstein College of in New York, acidity in diet is "probably more important than the amount of calcium in the diet." Deborah Sellmeyer of the University of California states that this metabolic acidosis is produced by eating "a lot of cheese, bread (to a lesser extent) and meat". In fact, a huge meta-analysis of over 87 different studies found that the amount of acid produced by typical diets in 33 countries can account for over two-thirds of the variation in hip fractures between these countries. "The richest, like Germany and Sweden with their high-protein meat, cheese and fish diet, had 40 times as many hip fractures as poorer nations like Thailand." And the Innuit that Byrnes refers to, who consume one of the highest amounts of animal protein, have the highest rate of osteoporosis in the world. As Deborah Sellmeyer summarises, "A high ratio of dietary animal to vegetable protein increases the rate of bone loss and the risk of fracture… "

Kidney Disease: Animal foods clearly do form acid in the body and so Byrnes' assertions here are simply spurious. Meat based diets are also much higher in protein which puts stress on the kidneys.

Heart Disease: Like any disease, risk factors are often offset by other factors. In the case of the French, their high per-capita meat consumption is offset by not only fresh vegetables and less junk food, but bioflavanols in the copious amounts of wine that they drink (the so called French Paradox). The same is true in the Mediterranean countries mentioned by Byrnes. Byrnes must be well aware that the causes of heart disease are quite a complex interaction of different factors, and singling out one, albeit important one, such as meat consumption in cultural comparisons without taking into account these other factors is likely to lead to confusing results. Meat is high in certain saturated fats which, compounded by one or more of the following factors — high stress levels in the body, genetic factors, high blood pressure, sedentary lifestyles, diabetes and smoking — will cause problems in the body such as thickening of arterial deposits. Vegetarian diets high in dairy and cheese products are often just as bad at putting these types of fats into our bodies and so are little healthier (vegetarians tend to live more conscious lifestyles, however, which reduces some of the other factors in heart disease). Vegan diets, on the other hand, are significantly healthier provided that they include essential fatty acids in the diet (from seeds and especially flax seed oil — although flax oil does not convert efficiently to DHA so it might also be a good idea to supplement with a vegetarian source of DHA). A healthy vegetarian diet can actually reverse the symptoms of arteriosclerosis as has been used successfully in many a raw food clinic.

Cancer: As with heart disease above, the cause of cancer can be quite complex, involving several factors. As Byrnes correctly points out, comparisons between different groups can be meaningless if most other factors are not taken into consideration, which is why many of the studies undertaken in this area of research seem to throw up conflicting information. That said, most dietetic researchers would agree that a vegetarian diet does significantly reduce certain forms of cancer, especially colon and stomach cancer. Apart from the carcinogenic content of cooked and processed meats in the intestinal system, this may be due to the higher immunity (100% higher NK cell activity) that German researchers have found in vegetarians. Another factor might be acidosis — the tendency of meat based diets to have an acidic effect on the internal environments in the body, something which actually encourages cancer cell growth. Examples of this cancer causing effect of meat are as follows: a study of 35,000 older women which showed that those with diets high in meat and animal fat, especially hamburgers, doubled the risk for lymph node cancer — also known as non-Hodgkin's lymphoma. And the Journal of the National Cancer Institute recently (1999) published research that indicated a link between high animal fat intake and prostrate cancer. In fact, every year more evidence is gathering as to the link between high meat consumption and cancer, which is why the American Cancer Society recommends, amongst other things, that to help reduce cancer, people need to "choose most foods from plant sources, limit intake of high-fat foods — particularly from animal sources." Byrnes' focus on religious groups is misleading as, similar to heart disease, other causative factors such as stress, relationships, background radiation, pollution, genetic disposition (many religious groups tend to keep quite genetically isolated). Although, just because there are other factors at work, does not mean that meat is not one of them!

Myth #6: Saturated fats and dietary cholesterol cause heart disease, atherosclerosis and/or cancer, and low-fat, low-cholesterol diets are healthier for people.

This, as Byrnes rightly points out, is not a vegetarian myth and is one that many researchers now agree with. (A vegetarian diet can be just as high in saturated fats as a meat based diet, although cholesterol is only found in animal products.) Personally, as a vegetarian, my preference has always been for butter over margarine any day as the hydrogenation process undertaken in the manufacture of margarine (poisonous nickel or other heavy metal catalysts are also used) produces a lethal cocktail of trans fatty acids and metal residues. Traditional margarines are one of the unhealthiest substances that we can take into the human bodies.

Fortunately, the dangers of trans fatty acids are only now starting to be acknowledged and in some countries maximum levels have been set (less than 0.1%) and margarine manufacturers are producing healthier products — although those in English speaking countries may contain a much higher amount (30-50%!). However, for many decades, margarine has been unfortunately cited as the healthy alternative to butter, and much damage has been done as a result. This may well be why some studies of certain groups of vegetarians show just as much atherosclerosis as meat-eaters. That said, the homogenisation of dairy milk is certainly cause for alarm as it increases the absorption of a substance called Xanthine Oxidase which destroys arterial walls, helping plaque to build up. Once again, the factors involved in atherosclerosis are complex and to single out saturated fat per se without any other consideration is foolish. More research certainly has to be done in this area, preferably with non-margarine eating vegans.

Myth #7: Vegetarians live longer and have more energy and endurance than meat-eaters.

Byrnes rightly points out that although vegetarians tend to live healthier lifestyles, it is difficult to ascertain whether increases in longevity are due to dietary influences or overall lifestyle choices (that include diet). Overall, vegetarians do live longer than meat-eaters, but there are so many other factors involved in longevity — such as genetics, culture, physical activity, beliefs, smoking, alcohol consumption, etc. — that is almost impossible to pin down the exact role that diet has. Studies that match people in all these influences tend to be small in scale (due to the difficulty in finding matches) and so statistically less significant.

Byrnes quotes Dr. Russel Smith's study as showing that a meat diet was healthier for "some" study groups. But with so many interrelated factors to take into consideration this sort of confusion and contradiction is what we might expect in comparing dissimilar groups of people. As Tarasuk and Brooker write in the September 1997 edition of the Journal of Nutrition, "A dietary factor which appears to be important may simply be acting as a proxy for some other factor which has not been measured but which is also commonly found in the dietary patterns observed… unless both factors are considered, it will be difficult to discern the true dietary effect". They go on to state that, "To be considered causal, an association between a specific dietary factor and disease occurrence should be observed consistently across a number of population-based studies, conducted by different research groups in different settings. Conclusions cannot generally be drawn from a single study." There is little point, therefore, in Byrnes quoting isolated studies whilst ignoring the main accumulating body of evidence.

Much of Byrnes' article focuses on the work of Dr. Weston Price, a dentist who did a tour of the world in the early 1930s to understand the effect of modern diet on teeth and health. (Byrnes is on the honorary board of directors of the Weston A. Price Foundation, so it is no surprise to see him base much of his article on Price's work.) Price noted that the traditional peoples around the world, who ate their traditional diets, were much healthier and had fewer dental cavities than their modern counterparts. He noted that much of the food they ate was raw and that they included animal products in their diets.

The problem with Price's work is that it was undertaken 70 years ago, in cultures that are very different from ours. Price, as with scientific understanding of his day, did not grasp the complexity of health and so relentlessly pursued a simplistic diet-based causality in his research, whilst ignoring many other factors such as genetics, lifestyle, physical exertion, mortality rates etc. Indeed, being a dentist, he may not have been the ideal person to judge how healthy an individual was outside of tooth health (which is not necessarily the best indication of health as malnourished people often have few cavities.) His research did indicate, as many others' have before and after him, that a modern diet of processed foods, high in sugar and refined flours, is decidedly unhealthy. We all know that. It is also undeniable that the less processing foods go through, the healthier they are to our bodies. However, drawing the conclusion that Price's research indicates that a meat-based diet is healthier than a vegetable-based diet is to draw a very weak inference from his observations, especially considering that "Price was on the lookout for a vegetarian culture, but he came up empty"—so he had nothing to make a comparison with. (In Price's day, vegetarianism was also unheard of in Western society, and so he would hardly be researching it per se.) Even just from a tooth cavity point of view, meat is not necessarily healthier as New Zealand has one of the highest per capita consumptions of meat in the world and yet suffers from some of the worst tooth decay. Byrnes also mentions that the largely vegetarian Hindus of southern India have the shortest lifespan in the world, but that is due largely to extreme poverty, extremely high infant mortality rates, overcrowding, and poor sanitation.

What Price does not mention is that many of the traditional people he examined had and continue to have shorter life expectancy than modern people and far higher infant mortality rates. When we see traditional people living to a very healthy old age it is easy to forget that for each one of them there are many others that died a lot earlier. Traditional lives are extremely tough which tends to weed out the weaker individuals, so that the old that survive tend to be stronger and healthier than the average Westerner of a similar age.

As for "fat-loading" before an athletic event, short one week periods of high fat diets may shave off a few seconds from an athletic performance as the body has become adapted at burning fat more efficiently, but to do this longer term is definitely not a healthy option. Fat adaptation is also unlikely to be the answer to increasing everyday stamina for non-athletes.

Myth #8: The "cave man" diet was low-fat and/or vegetarian. Humans evolved as vegetarians.

There is no evidence that early humans were vegetarians, and it is very likely that most had hunter-gatherer diets that included meat. (The fact that certain essential nutritional factors such as B12 which can only be found in animal product diets indicates that humans must have had meat-based diets for considerable period of time.) When survival is difficult and you can't digest cellulose, you need to be able to be quite flexible in terms of diet. Of course, what is essential for survival is not necessarily what is best for health: the biological success of a population depends only upon its reproductive success, not on overall lifespans and health into old age. In fact, animal product diets are known to shorten the time to reproductive maturity. So just because the diet on which humans developed was likely to be predominantly meat-based and very high in fat, does not mean that this diet is the most healthful for people today for whom overall health and longevity is at least as important as reproductive success.

Having said that, the meat and animal products available to most of us today are a far cry from those eaten by our ancestors. Today we live longer, sedentary lifestyles with exposure to a huge array of toxins and chronic psychological stresses. Under these conditions a Palaeolithic diet may not be as healthful as some popular diet books would suggest. Humans may well have had extended periods during their evolution on a meat-based diet, but we are a long way from having the physiology of carnivores. Evidence is suggesting that a vegetarian diet, with the appropriate vitamin and mineral supplementations, may well be the most healthful diet that we could possibly choose for living today.

Myth #9: Meat and saturated fat consumption have increased in the 20th century, with a corresponding increase in heart disease and cancer.

Meat and diary products in the early part of the 20th century are very different product to what we see on our supermarket shelves today. The mass production of these foods has meant that processing techniques have had to be introduced which had not only allow "fresh" products to appear in all supermarkets nationwide, but makes them quite deadly in the process. And of course, other processing that has gone on with other products makes modern processed food poisonous biologically. (Even raw cuts of meat are rife with bacteria, parasites and toxins.)

So there is little point making comparisons of heart disease and cancer rates with people living 100 years ago. The only point that Byrnes can rationally make is that cleanly produced meat, with a low bacteria, parasite and toxin level, was not a primary cause of heart disease and cancer for the average person living in the context of life in the first half of the 20th century and before. Today is quite a different matter, and new research, rather than invalid historical comparisons, is necessary to find which group of factors is important for modern societies.

Myth #10: Soy products are adequate substitutes for meat and dairy products.

Soy products are not necessarily the health food that they are currently being marketed as, and Byrnes does all of us a favour in reminding us of this fact. Nexus Magazine published a very good article on the dark side of soy products here and there is a great site dedicated to the whole issue here. The problem is that the soy industry, which has grown extremely rich supplying much of the world's animal feed, has jumped on the health bandwagon and are using their huge political and economic clout to pushmodern-processed soy as a health product.

There are two basic types of soy: modern-processed soy — textured soy protein and soy milk— and more traditionally fermented soy. The fermentation process is actually essential for turning the soy product into a health food. Without that process, soy should not be consumed in large quantities. (If you drink soy milk you might try rice or oat milk — a delicious alternative.)

There has also been a lot of bad press recently on the oestrogen-mimicking ability of the isoflavones in soy. This is, however, a misconception based on the confusion between harmful 4,16-hydroxyestradiol and healthy 2-hydroxyestradiol (we have two different types of oestrogen receptor). Soy isoflavones tend to increase the latter and so cannot be regarded as unhealthy in this aspect — in fact they are now considered to be very healthy.

Overall, fermented soy most certainly can be a healthy subsitute for meat and dairy products, in fact it forms the staple diet of some of the longest-lived people in the world, those in Okinawa, Japan. Older Okinawans eat up to 80g of tofu a day. For a healthy perspective of soy, visit www.vegan.org.nz/soy.php.

Myth #11: The human body is not designed for meat consumption.

Like that of other primates, the human digesting system can cope with many different diets, including meat-based, vegetarian (although some vegetable matter needs to be cooked to release the nutrition), fruitarian and omnivorous. Humans seem to be remarkably adaptable to different diets. Quite what we have been "designed" for is open to conjecture, and probably the most accurate statement would be to say that we have been designed to be quite flexible in our diets.

Anatomical comparisons are useful only as a rough guide of what food types we can cope with or not (for example, we do not have a ruminant, and so we could never be grazers) but in nature, the rule of the game is survival to reproduction and not optimum life-span and wellbeing. Our pretty universal digestive system has been pivotal in making the human species one of the most successful on this planet, and also means that we have the design to pretty much choose which diet we want to follow (although the more restrictive the diet, the more the possibility that certain nutritional needs will not be met).

Myth #12: Eating animal flesh causes violent, aggressive behaviour in humans.

The statement that Byrnes makes in brackets in the following quote is astonishing. He states, "the fear and terror (if any; see Myth #15) an animal experiences at death… " If any??? I am sure if Byrnes visited to a modern abattoir he would describe the very visible fear of these poor animals as "a simple autonomic response to an unfamiliar environment". And he mockingly says that this supposed fear "somehow" gets transferred to the flesh and organs. This is from a doctor who must be well aware of the hormone system in the body, and that fact that adrenaline and other hormone levels in the deceased can give an indication in autopsy of stress levels at time of death. As for Price's note of extreme happiness and ingratiating natures of the peoples he encountered, considering that Byrnes states that Price didn't find a single totally vegetarian culture, this observation cannot be used to condone a meat-based diet, but probably does say something about primitive society and culture.

Myth #13: Animal products contain numerous harmful toxins.

It is accepted scientific fact that animal products are potentially a lot more toxic than vegetable products. They do contain parasites, salmonella, hormones, nitrates and pesticides. As Eric Schlosser reports in his book Fast Food Nation, "A serious of tests conducted by Charles Gerba, a microbiologist at the University of Arizona, discovered far more fecal bacteria in the average American kitchen sink [from meat] than on the average American toilet seat. According to Gerba, "You'd be better off eating a carrot stick that fell in your toilet than one that fell in your sink." And there is little point stating that some of these toxins are also in "commercially raised fruits, grains and vegetables" as the vast difference in levels and extensiveness makes the comparison misleading. Animals concentrate pesticide levels in their feed and toxins in the environment, and are exposed to extremely toxic chemicals during their lives. Animal products are also far more susceptible to bacterial infection. And although theoretically true, it is a very weak assertion that "Salmonella can be transmitted by plant products as well. " When a family member or friend gets food poisoning, the first thing we think of is what meat, eggs or dairy products he or she might have eaten!

Much of the toxic levels in animal produce are a result of how the meat is produced, handled, and how old it is when it is eaten. There is little point bringing up Price's observation of health in traditional societies that eat meat (often raw) because there are so many other factors to take into consideration that comparison to the modern diet is invalid. Byrnes then discusses Pottenger's observation that a raw meat diet is better than a cooked meat diet for cats, which of course has nothing to do with whether meat is good for you or not, but more to do nutritive destruction by heat. His point that the cats feed cooked meats had numerous parasites where as those that ate raw didn't seems misplaced considering that just a paragraph earlier he states that "Parasites are easily avoided by taking normal precautions in food preparation."—which presumably means cooking.

Finally, Byrnes harps on about Mark Purdey's very probable theory on the cause of BSE and how it was caused by organophosphates and "not cuased by cows eating animals parts in their food". This is a little odd as investigative journalist, George Monbiot, states in an article supporting Purdey's theory, "Mark Purdey accepts that the horrible practice of feeding dead animals to cows has a role in the development of the disease."

Myth #14: Eating meat or animal products is less "spiritual" than eating only plant foods.

Religions have grown over the generations and have had to endorse a meat diet because under the circumstances of the past, a vegetarian diet was often not feasible for the survival of the nation. But now, as people become more aware of diet and its impact in terms of the suffering of animals, more are choosing to minimise their impact. Religions evolve, and today there are strong groups of Christian vegetarians (and I am sure they are aware that Jesus ate meat), Jewish vegetarians (the Chief Rabbi of Ireland, David Rosen, has stated that "the consumption of meat is halachically unacceptable."), Hindu vegetarians (in fact there are more faith based vegetarians in India than any other place in the world) and Muslim vegetarians (the Prophet Mohammed stated that it "there is a meritorious reward for kindness to every living creature".)

The Dali Lama comes from a Tibetan monastic culture where meat was an important for survival, and yet he has stated that given the choice he prefers a vegetarian diet because it minimises the suffering of other creatures. The world does move on as it becomes more aware. Israel, for example, has now the largest number of faith based vegetarians in the world outside India — and this is a country that that Byrnes rightly points out has involved meat in its religious rituals for thousands of years!

Byrnes comes up with an unusual justification for meat-eating by stating that if we didn't eat meat, the "life force would become cancerous". Presumably by the same reasoning, we should congratulate ourselves on our healthy homicide rates. What strikes me about Byrnes's response here and in the next section is its total lack of compassion and empathy. This is an intellectual response — cold and academic — and one can see why such a man has difficulty understanding why some people should be vegetarians, outside of the intellectual stance that "philosophical problems with animal flesh must be respected".

Myth #15: Eating animal foods is inhumane.

Without question, MOST commercially raised livestock live in deplorable conditions! There is no need to go to Korea to find animal suffering for it is endemic to the Western agribusiness system that supplies 90% of our animal food supplies. (If you don't believe me, just visit your average slaughter house or factory farm.) There is little point Byrnes stating that "our recommendations for animal foods consumption most definitely do not endorse such practices" because it would be impossible to supply a whole nation with meat from small "humane" farms. There just isn't the land or the profitability for that sort of luxury. So by recommending an animal diet, you can only but support cruelty to animals.

It is also remarkable that Byrnes' only complaint against commercial farming is that it produces "an unhealthy food product". He goes on to recommend organic production because it is "cleaner and more efficient". Not a single word about animals' feelings and wellbeing outside of affecting the quality of the finished product! Clearly Byrnes is a man who sees animals as meals on legs. (His choice of links at the end of his article show his lack of compassion towards animal suffering.)

Of course it is possible to raise animals humanely, but is the brutality in killing them ever humane? It is naïve of Byrnes to state that dairy products and eggs are somehow separate from this deadly trade when under the current system that supplies just about all our eggs and dairy products (including the organic industry), when an animal is no longer able to sustain a ridiculously high level of milk or egg production, they are immediately killed for their meat. (Egg-laying chickens also have their beaks cut off so that they don't peck each other in the cramped conditions in which they are invariably raised.) Dairy production, egg production and the meat industry are part of the same process in most farms. And his weak observation at the end that the growing of crops involves many animal deaths anyway is a bit like saying that because some people die under medical care that we should not bother caring at all. Byrnes once more shows himself to be completely unable to understand a heart-felt intention.

Perhaps the best judge on inhumanity is someone who has suffered it to the extreme. Edgar Kupfer wrote in Dachau, a Nazi concentration camp, "I refuse to eat animals because I cannot nourish myself on the suffering and by the death of other creatures. I refuse to do so because I have suffered so painfully myself that I can feel the pains of others by recalling my own sufferings."

Biochemical, Genetic Individuality and Conclusion

There is metabolic variance within the human species which means that there is no one diet that will suit everyone. Usually, it is best to follow your instincts when it comes to choosing food, but these can often be warped by the addictive quality of high fat, high sugar and high salt fast food that so many of us gorge ourselves on today. Byrnes is right in saying that humanity evolved on a diet that often had a significant meat content. But it does not necessarily follow that following that sort of "caveman" diet will necessarily be healthful, as the animal products today are entirely different from those of times past (even chicken, which is often considered healthy, had a far higher fat content than it did just a few decades ago), and modern man has to cope with many other factors such as pollution, an extended lifespan, higher health expectations into old age, chronic stresses, drugs (both prescription and recreational), sedentary lifestyles, and dietary foods (such as margarine and milk) that are extremely unhealthy. Quite what the consequences of this modern cocktail of factors is to our health must be investigated by science today, and not by completely invalid historical comparisons, where these other factors, including genetics, are completely ignored.

Evolution is about species survival, and does not have a much to do with optimising either lifespan or health after reproductive years. Often some of the most badly nourished and unhealthy societies on our planet have the highest population growth rate, which from an evolutionary point ensures the survival of the species. Natural selection only selects for those that are fittest in reproducing. But modern society is entirely different. The weaker ones of us are not weeded out as they were in primitive societies with their extremely high infant mortality rates, and we grow up in a world with entirely different biological stressors. And after giving birth, most modern women expect to live at least another 30 to 50 years or more. The sort of diet that is optimum for this sort of existence is unlikely to be the same as that of our Neolithic ancestors. What is more, the density of people living on the planet now requires entirely different methods of food production, methods that could never supply us with the diet of a hunter/gatherer — a diet that requires vast areas to feed small numbers of people.

Should we include some animal products? If we are a vegetarian, it is perfectly possible with modern supplements (such as B12 supplements among others) to get all the factors that we need and still maintain an almost complete vegetarian diet. In this way suffering on the planet can be minimised. Just because the whole human race cannot be completely vegan without some supplementation (either artificial health supplements or with some animal products) does not mean that vegetarianism is unhealthy or that that we should not bother because it is an unattainable ideal. (Human rights is an ideal but because universal recognition of them is currently unattainable in the world does not mean that we should not strive for their application.) Our existence, even a vegan's, is very much dependent on animals (even car tires contain gelatine). But only an uncivilised society would not try to minimise the suffering of other creatures. Given the technology that we have, and our dietary know how (which could always be better but is certainly workable), it is now perfectly possible to be vegan and still be healthy. In fact, there the bulk of evidence does indicate that vegans and vegetarians have lower mortality from certain degenerative diseases, although more research needs doing.

Byrnes quotes H. Leon Abrams at the end stating that vegetarians "suffer from debilitated conditions of health". This is only true when vegetarianism is combined with extreme poverty (in a resource sense of the word), so that the diet is not only completely inadequate but there are numerous other factors leading to ill health. (Unless one has the land resource to hunt and gather, meat eaters can often be just as undernourished when faced with a lack of resources.) One such place that has this combination of poverty and vegetarianism happens to be India, which has the most vegetarians of any society in the world. It is pointless drawing the conclusions that vegetarians are unhealthy because most of them (which happen to live in India) are unhealthy. The only reliable comparison can be made with vegetarians in more afflulent societies, and they are at least as healthy, if not more, than their meat-eating counterparts.

Author's Notes:
The author would like to thank Sally Fallon, MA; Lee Clifford, MS, CCN; and Dr. H. Leon Abrams, Jr., for their gracious assistance in preparing and reviewing this paper.

This paper was not sponsored or paid for by the meat or dairy industries.

About the Author:
The late Stephen Byrnes, PhD, RNCP, is the author of Diet & Heart Disease: Its NOT What You Think and Digestion Made Simple (Whitman Books; 2001); and The Lazy Person’s Whole Foods Cookbook (Ecclesia Life Mana; 2001).