Saturday, 20 April 2013

10 reasons to become a vegetarian, and the science to back it up

Working as a programmer is not really promoting good health, sitting in front of computers 10 hours a day often with work related stress. Since a kid I have had a condition of Atopic Dermatitis which comes with a weakened immune system, so naturally I look for ways to strengthen my immune system.

This year I have decided to become a semi-vegetarian in order to stay healthy. Becoming more vegetarian also has many other benefits so I have compiled a list of benefits to encourage others to also consider cutting down on animal based foods.

Reasons to become a vegetarian

  1. Better health.
  2. Prevent cancer. 
  3. Weight control.
  4. Healthy mind. 
  5. Save the environment.
  6. Support sustainable development.
  7. Ethics.
  8. Reduce the effects of aging. 
  9. Save money.
  10. Smart people tend to become vegetarians.


1. Better health

The combined results from five studies in 1999 involving more than 76,000 people compared the incidence of disease among vegetarians to that of nonvegetarians with similar lifestyles. Mortality from heart disease was 24% lower in vegetarians than nonvegetarians [1].

A number of environmental toxins build up in animal tissues and are found in meat. According to the FDA, studies suggest that exposure to dioxin-like compounds (DLCs) may lead to a variety of adverse health effects, including reproductive and developmental problems, cardiovascular disease, increased diabetes and increased cancer [2],[3].

A 1985 Swedish study demonstrated that individuals with asthma practicing a vegan diet for a full year have a marked decrease in the need for medications [4].

A vegetarian diet contains more antioxidants. Antioxidants mop up free radicals that cause chronic inflammation [5],[6],[7].

Gout [8], kidney stones [9] and other diseases are also associated with an animal based diet.

Avoid consuming residues of antibiotics, veterinary drugs, heavy metals and other non-degrading toxins. According to an analysis of U.S. Food and Drug Administration data by the Johns Hopkins University’s Center for a Livable Future, 80% of all antibiotics sold in 2009 were for use on livestock and poultry [10].

You seldom get sick from a vegetable but food poisoning from Escherichia coli, Campylobacter, Salmonella etc in meat and seafood is not unusual [39].

2. Prevent cancer

Large studies in England and Germany have shown that vegetarians are about 40% less likely to develop cancer compared to meat-eaters [11][12].

Vegetarians avoid animal fat linked to cancer and get abundant fiber, vitamins, and phytochemicals that help to prevent cancer. Vegetarians also have a higher level of white blood cells that attack cancer cells [13].

Several studies published since 1990 indicate that cooking meat creates heterocyclic amines (HCAs) [14] which can cause cancer.

Residues of artificial hormones that are widely used to promote growth in beef cattle, dairy cows and sheep may increase the risk of breast, prostate and colorectal cancer in humans [15],[16].

3. Weight reduction

A study in 2009 found that vegetarians and vegans had body weights 3% to 20% lower than meat eaters [17].

Cutting out red meat in general is associated with lower body weight [18],[19].

4. Healthy mind

Cholesterol is now linked to Alzheimer’s decease [20],[21]. Plants do not contain cholesterol.

There is also a trend towards delayed onset of dementia in vegetarians [22].

5. Save the environment

In Latin America, 20 million hectares of tropical forest have been converted to cattle pasture since 1970. Deforestation has had a devastating impact on plant and animal diversity in Latin America [23].

Pound for pound, beef production generates greenhouse gases that contribute more than 57 times as much to global warming as do the gases emitted from producing potatoes [24].

According to the United Nations Food and Agriculture Organization (FAO) there are 1.4 billion cattle and 1.1 billion sheep on the planet producing 37% of the total methane generated by human activity. Methane is 20 times more potent at trapping greenhouse gases than carbon dioxide [25].

In a study in California from 2009 researchers found that a nonvegetarian diet required 2.9 times more water, 2.5 times more primary energy, 13 times more fertilizer, and 1.4 times more pesticides than a vegetarian diet [40].

An assessment from 2002 in the Netherlands suggests that on average the complete life cycle environmental impact of nonvegetarian meals may be roughly a factor 1.5–2 higher than the effect of vegetarian meals in which meat has been replaced by vegetable protein [41]. A recent study in the Journal of Climatic Change from 2014 [42] came to just about the same conclusion.

On average vegetarian diets have an environmental advantage but exceptions may occur. Long-distance air transport, deep-freezing, and some horticultural practices may lead to environmental impacts exceeding those for locally produced organic meat. Keep in mind that on a large scale organic meat has higher carbon footprint as it requires more land which means less forest to bind carbon dioxide.

6. Supporting sustainable development

The rising animal based food intake is related to several global crises such water, climate, and energy [26].

One pound of pork that provides between 1000 and 2000 calories takes 14,000 calories of energy to produce [27].

Several places on the planet are experiencing a water shortage. The production of meat requires between six and twenty times more water than for cereals [28].

The increasing global water crisis is already affecting some regions of the world (in 10-20 years the icecaps in the Himalayas will be gone, major source of water for India and China) [29].

China and India are also booming economies, and their meat and dairy consumption has increased significantly in the last decades. In China the number of adults with more than 10% of their caloric intake from these animal foods increased with 17.6% from 2000 to 2006 [30].

A growing human population is increasingly relying on unsustainable agricultural practices. As world population approaches nine billion, global food demand is expected to double in the next fifty years [31]. Because of the increased food demand, we as a species run the risk of depleting our natural resources and degrading the environment.

8. Ethics

Avoid the mass slaughtering of animals for your pleasure. 10 billion land animals were raised and killed for food in the United States in 2010 [32].

Although direct measurement of subjective experiences or emotions in farm animals is not possible they do feel pain [33]. By reducing your meat intake you decrease the market demand for animal based food. Less demand means less need for factory farming which is often associated with animal cruelty [34].

9. Reduce the effects of aging 

Evidence suggests that eating whole fruits, vegetables, and whole grains, all rich in networks of antioxidants, provides protection against many of these signs of aging [35].

Antioxidant-rich foods seem to have a protective effect for the skin [36].

7. Save money

Reduce your future health care costs. The total annual US medical costs attributable to meat consumption have been estimated to something in the order of 30-60 billion $ [37].

Vegetables can be stored longer before it has to be thrown away and it tends to cost less. Vegetarian meals at restaurants usually cost less than other meat dishes.

10. Smart people tend to become vegetarians

In a British study of more than 8,000 participants IQ was measured over a period of 20 years starting at age 10. The study showed that higher IQ had a strong correlation with being a vegetarian [38].

If not science can convince you of cutting down on meat then maybe role models can. Albert Einstein, Sir Isaac Newton, Darwin, Pythagoras, Leonardo Da Vinci, Nikola Tesla and Thomas Edison were all vegetarians.

11. (Bonus) Build personal strength

By cutting down on meat you make a conscious choice. It shows that you care and are willing to make sacrifices. This helps to build character. By reducing your meat consumption you will not save the planet but you will improve your health, build personal integrity and strength, as well as contributing to a better world  for all


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