Review finds Vegetarian Diets Beneficial for Blood Pressure

by | Jan 14, 2016 | 2014, Blood Pressure, Cardiovascular Health, Vegetarianism

Written by Greg Arnold, DC, CSCS. The researchers found that consumption of a vegetarian diet resulted in a significant drop in blood pressure.

High blood pressure is one of the most significant risk factors for cardiovascular disease and heart disease, accounting for 1 in 3 of all U.S. deaths and costing our healthcare system $473 billion in 2009 (1)). The condition also causes the heart to thicken over time due to increasing its workload, also leading to an increased risk of stroke, heart attack, kidney failure and congestive heart failure (2). This has led to blood pressure being deemed a worldwide epidemic (3). The National Institutes of Health classify a healthy blood pressure as 120/80 mmHg or less, a blood pressure between 120/80 and 140/90 as “pre-hypertension”, and 140/90 mmHg or greater as high blood pressure (4).

Now a new study (5) suggests that following a vegetarian diet may help maintain a healthy blood pressure. In the study, researchers identified seven controlled trials (a total of 311 participants; mean age, 44.5 years) lasting an average of 15.7 weeks, six of which were randomized controlled trials (6-11).   The researchers found that consumption of a vegetarian diet resulted in an average drop of 4.8 mmHg in their systolic blood pressure (the top number, p < 0.001) and a 2.2 mmHg drop in the diastolic blood pressure (the bottom number, p < 0.,001) compared to those consuming an omnivorous diet (both meat and vegetables).

They then looked at 32 other types of studies called observational studies, consisting of  21,604 subjects with an average age of 46.6 years. They found that consumption of vegetarian diets reduced systolic blood pressure by an average of 6.9 mmHg (p < 0.001) and reduced diastolic blood pressure by 4.7 mmHg, p < 0.001) compared with the consumption of omnivorous diets.

When suggesting why vegetarian diets may be beneficial for blood pressure levels, the researchers pointed to studies showing potassium to be abundant in vegetarian diets (12) which is thought to increase blood vessel relaxation and kidney function while decreasing blood clotting (13). While some studies suggest a decreased sodium intake as another mechanism (14), not all studies have found this to be so (12).

For the researches, “Consumption of vegetarian diets is associated with lower blood pressure” and that “such diets could be a useful nonpharmacologic means for reducing blood pressure.”

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

Source: Yokoyama, Yoko, et al. “Vegetarian diets and blood pressure: a meta-analysis.” JAMA internal medicine 174.4 (2014): 577-587.

© 2014 American Medical Association. All rights reserved.

Posted April 14, 2014.

References:

  1. “Cardiovascular Disease at a Glance” posted on the CDC website.
  2. “Risk Factors for Coronary Heart Disease” posted on The American Heart Association Website.
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  4. “What Is High Blood Pressure?” posted on the NIH Website.
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  6. RouseIL, Beilin LJ, Armstrong BK, Vandongen R. Blood-pressure–lowering effect of a vegetarian diet: controlled trial in normotensive subjects. Lancet. 1983;321(8314-8315):5-10.
  7. Margetts BM, Beilin LJ, Vandongen R, Armstrong BK. Vegetarian diet inmild hypertension: a randomised controlled trial. Br Med J (Clin Res Ed). 1986;293(6560):1468-1471.
  8. Kestin M, Rouse IL, Correll RA, Nestel PJ. Cardiovascular disease risk factors in free-living men: comparison of two prudent diets, one based on lactoovovegetarianismand the other allowing lean meat. Am J Clin Nutr. 1989;50(2):280-287.
  9. Nicholson AS, Sklar M, Barnard ND, Gore S, Sullivan R, Browning S. Toward improved management of NIDDM: a randomized, controlled, pilot intervention using a lowfat, vegetarian diet. Prev Med. 1999;29(2):87-91.
  10. Sciarrone SE, StrahanMT, Beilin LJ, Burke V, Rogers P, RouseIL. Biochemical and neurohormonal responses to the introduction of a lactoovovegetarian diet. J Hypertens. 1993;11(8):849-860.
  11. Hakala P, Karvetti RL.Weight reduction on lactovegetarian and mixed diets: changes in weight, nutrient intake, skinfold thicknesses and blood pressure. Eur J Clin Nutr. 1989;43(6):421-430.
  12. Rizzo NS, Jaceldo-Siegl K, Sabate J, Fraser GE.  Nutrient profiles of vegetarian and nonvegetarian dietary patterns. J AcadNutr Diet. 2013;113(12):1610-1619.
  13. McDonough AA, Nguyen MT. Howdoes potassium supplementation lower blood pressure? AmJ Physiol Renal Physiol. 2012;302(9):F1224-F1225.
  14. Larsson CL, Johansson GK. Dietary intake and nutritional status of young vegans and omnivores in Sweden. Am J Clin Nutr. 2002;76(1):100-106.