Research Review Links Vegetarian Diet to Better Cellular Health

by | Oct 30, 2012 | 2012, Cancer, Cardiovascular Health, Fruits and Vegetables, Vegetarianism

Written by Greg Arnold, DC, CSCS. In a review that included 124,706 vegetarians, vegetarian diets reduced the death rate, heart disease, and cancer.

The number of Americans who consider themselves vegetarians has grown from 1% of the population (2 million Americans) in 1971 (1) to 2.4% of the population (7.3 million Americans) in 2008 (2, 3). It is generally believed that a vegetarian diet is healthier than a non-vegetarian diet, but it’s been shown that vegetarians are frequently deficient in B-vitamins (4). The large Adventist Health Study (5) did show vegetarian diets reduce the risk for some cancers like colon and prostate cancer, however the large Oxford Vegetarian Study (6) did not show significant reduced risks for breast or colorectal cancer. Now a new review of the research (7) looked at seven studies on vegetarianism consisting of 124,706 subjects ranging in age from 10 to 90 and lasting between 10 and 23 years (8,9,10,11,12,13,14). The term “vegetarian” included lacto-ovo vegetarians (no meat or fish or ate them less than once a week, but did eat eggs and/or dairy products) and vegans (no meat, fish, eggs or dairy products).

For specific diseases, the researchers found the following for vegetarians vs.
non-vegetarians:

  •  A 9% lower risk from all causes of death, consistent with previous studies (p = 0.089) (15)
  • A 22% lower risk of death from ischemic heart disease, similar to previous studies (16,17) but this risk reduction was only present in those who had been vegetarians for more than 5 years (p = 0.076)
  • A 16% lower risk of death from circulatory diseases such as heart attack and stroke (p = 0.046)
  • An 18% overall lower risk from cancer (p = 0.087) though the researchers did not look at specific cancers.

Other than ischemic heart disease, the researchers did not go any further into duration of vegetarianism and disease risk. They emphasized the low-fat characteristic of vegetarian diets as “high-fat diets are implicated in the onset of cardiovascular disease, cancer and obesity” and that “large intakes of saturated and trans fatty acids, together with low levels of…omega-3  polyunsaturated fatty acids, appear to have the greatest impact on the development of cardiovascular disease.”

For the researchers, “Our results suggest that vegetarians have a significantly lower ischemic heart disease mortality and overall cancer incidence than non-vegetarians.” However it should be noted that although the study includes a very large number of participants, the p values are higher than the 0.05 level that is usually regarded as meaningful, and further research needs to be done in this area.

Source: Huang, Tao, et al. “Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review.” Annals of nutrition and metabolism 60.4 (2012): 233-240.

© 2012 S. Karger AG, Basel

Posted October 30, 2012.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com

References:

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  2. 2008 report: “Vegetarianism in America” posted on Vegetarian Times website
  3. US population statistics obtained from the US Census website
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