Efficacy of vitamins for coronary heart disease
Micronutrients and specific foods are studied as substances for reducing the risk of cardiovascular diseases (CVD). Common supplements that many use to reduce the risk of heart disease include multivitamins, vitamins B and folic acid, antioxidants such as vitamins E and C, various carotenoids and ubiquinone (coenzyme Q10).
Foods that can reduce cardiovascular risk (SSR) are whole grains, fiber, fish and fish oil, and soy protein. Observational studies have shown a lower incidence of CHD among those who use antioxidant vitamins and folic acid, but the results of the research are contradictory and their effect is modest.
The significance of randomized clinical trials for heart-healthy foods and nutrients is best illustrated by a description of the advantages and disadvantages of vitamin E. In fundamental research, there is strong evidence that oxidative stress plays an important role in the development of diseases caused by atherosclerosis, and vitamin E can slow down or prevent various stages of atherosclerosis.
By the mid-1990s. observational studies have convincingly shown that high doses of vitamin E reduce the risk of CHD, especially with secondary prophylaxis. However, completed secondary prevention studies have revealed that the addition of vitamin E has little effect on the risk of coronary heart disease (CHD). Similar results were obtained in two long-term primary prevention studies – the Women’s Health Study and the SU.VI.MAX (Supplementation en Vltamines et Mineraux AntioXydants), which evaluated a combination of antioxidants, including vitamin E in a dose of 30 mg.
No significant reduction in the risk of cardiovascular disease (CVD) was found in these studies.
In the study of the cardiovascular effects of antioxidants in women in the framework of secondary prophylaxis, no positive cardiovascular effects were found among those taking any antioxidant: vitamin E, vitamin C or β-carotene for> 9 years. In the GISSI study, 11,324 patients who recently had myocardial infarction were divided into groups:
(1) taking daily supplements containing 1 g of omega-3 PUFA;
(2) taking vitamin E at a dose of 300 mg;
(3) receiving both supplements;
(4) not taking anything.
Observation was conducted 3.5 years. Treatment of omega-3 PUFA, but not vitamin E, reduced the relative risk of the primary endpoint (death, non-fatal MI and MI) by 10% (95% CI 1-18). This beneficial effect was primarily due to the reduced risk of death, and not due to nonfatal MI or cerebral stroke (MI).
Finally, in numerous prospective cohort studies, plasma homocysteine levels have been consistently associated with increased vascular risk. On this basis, it was hypothesized that a decrease in homocysteine with folic acid would lead to a decrease in the frequency of vascular events. However, numerous studies with the addition of folic acid to patients with vascular disease did not reveal a favorable clinical effect.
Recommendations. There are no results of studies supporting the use of food supplements for the prevention of KBS or other cardiovascular events (SSSob). Antioxidants did not show a clear benefit in preventing CHD, but observational studies revealed the possibility of various micronutrients and specific foods to reduce the risk of coronary heart disease (CHD). However, soy protein and isoflavone supplements lost their popularity in 2006, when the ANA, which had previously recommended soy, changed its position after analyzing the results of 22 studies, saying that it could not recommend supplements of isoflavones in pills or in food to prevent heart disease.
More research is needed on fish oil supplements before offering general recommendations. Several recent studies have failed to reveal the benefits of folach supplementation, thus showing that a decrease in homocysteine is not associated with a reduction in vascular risk.