Individuals choosing to follow a vegan diet do not eat meat or products derived from animals, such as dairy products and eggs. Many features of a vegan diet are believed to have a protective effect against heart disease. It is well-documented that high intakes of saturated fat from red meat can increase blood cholesterol levels leading to an increased risk of cardiovascular disease. This has led some to suggest that following a vegan diet for heart disease could help both in treatment and prevention.
Saturated Fat and Cholesterol
High cholesterol levels are linked to an increased risk of heart disease. Excess cholesterol can accumulate in the blood vessels, leading to atheroscelerosis (narrowing of the arteries). The proportion of different lipoproteins in the blood is important in maintaining a healthy cholesterol level. Lipoproteins are involved in the transport of cholesterol around the body, and a high level of low-density lipoprotein (LDL), or a low level of high density lipoprotein (HDL), are both associated with increased blood cholesterol levels.
Replacing saturated fats with complex carbohydrates has been shown by Clarke et al (British Medical Journal, 1997) to have a significant effect on cholesterol levels, reducing them by 10 to 15 percent. Red meats in particular are high in saturated fats. Vegan diets contain considerably less saturated fat due to the lack of red meat and dairy products.
Vegans Eat More Fiber
It is estimated that most vegans consume between 50 and 100 percent more fiber than non-vegans, and this can have a range of health benefits associated with decreased risk of heart disease. High-fiber diets have been linked with more favorable lipoprotein profiles, thus resulting in a lower risk of heart disease. Soluble fiber has also been shown to reduce risk of heart disease by lowering blood cholesterol.
Folic Acid from Leafy Greens
Those following a vegan diet tend to consume a much larger proportion of fruit and vegetables in their diet than their omnivorous counterparts. Many types of fruit and vegetables are high in folic acid: especially leafy greens. Folic acid has been shown to help reduce homocysteine levels, resulting in a decreased risk of heart disease.
A study by DeRose et al published in the journal Preventative Medicine in 2000 imposed a vegan diet on a number of healthy subjects together with other lifestyle restrictions such as physical exercise, stress management and exclusion of alcohol and tobacco. Plasma homocysteine levels were significantly reduced after just one week of intervention. Due to the imposition of further lifestyle changes, this study cannot provide conclusive evidence that the vegan diet was responsible for this change.
Vegan Diet For Heart Disease Versus Vegetarianism
Those following a vegan diet are at significantly lower risk of developing heart disease than lacto-ovo vegetarians, according to a study by Thorogood et al published in the British Medical Journal in 1987. Although all forms of vegetarianism exhibited a reduced risk of developing heart disease when compared with the meat-eating group, incidence of coronary heart disease in life-long vegetarians was only 24 percent lower, compared with a 57 percent decrease in risk for life-long vegans.
Vegan Diet May be Useful in Treatment
A study by Sanders et al published in the _American Journal of Clinical Nutritio_n in 1978 measured a number of features related to risk of heart disease in vegan subjects and compared them with matched non-vegan controls. The vegan group exhibited lower weight and skinfold thickness than the control group, suggesting obesity is less likely when following a vegan diet. The vegan group had a higher proportion of linoleic acid and a markedly lower cholesterol level than the control group. The researchers suggested that a vegan diet may therefore be beneficial in the treatment of ischemic heart disease and angina.
GA Spiller, B Bruce “Vegan Diets and Cardiovascular Health” Journal of the American College of Nutrition 17:407-408 (1998)
“Cholesterol and Lipoproteins” Heart UK
R Clarke, C Frost, R Collins “Dietary Lipids and Blood Cholesterol: Quantitative Meta-Analysis of Metabolic Ward Studies” British Medical Journal 314:112 (1997)
Council on Scientific Affairs “Dietary fiber and health” Journal of the American Medical Association 262:542–546,(1989)
H Refsum, PM Ueland, O Nygard “Homocysteine and Cardiovascular Disease” Annual Review of Medicine 49:31-62 (1998)
DJ DeRose, ZL Charles-Marcel, JM Jamison “Vegan Diet-based Lifestyle Program Rapidly Lowers Homocysteine Levels” Preventative Medicine 30:225-233 (2000)
M Thorogood, R Carter, L Benfield “Plasma Lipids and Lipoprotein Cholesterol concentrations in People With Different Diets in Britain” British Medical Journal Clinical Research Edition 295-351 (1987)
TAB Sanders, FR Ellis, FRC Path “Studies of Vegans: The Fatty Acid Composition of Plasma Choline Phosphoglycerides, Erythrocytes, Adipose Tissue and Breast Milk. and Some Indicators of Susceptibility to Ischaemic Heart Disease in Vegans and Omnivore Controls” American Journal of Clinical Nutrition 31:805-813 (1978)