A recommendation was issued that intake of beta-carotene and vitamin E for the prevention of cardiovascular disease and cancer actually increases the harm. The conclusion is that multivitamins are also insufficient to evaluate benefits.
The U.S. Preventive Services Task Force (USPSTF) released a statement of advice on supplement intake for the prevention of cardiovascular disease and cancer on the 21st.
Cardiovascular disease and cancer are the leading causes of death and account for regarding half of all deaths in the United States annually. Inflammation and oxidative stress affect both cardiovascular disease and cancer, and supplements such as dietary supplements can have anti-inflammatory and antioxidant effects, which is why a diverse population is taking them.
In fact, according to the National Health and Nutrition Examination Survey data, 52% of US adults surveyed reported using at least one dietary supplement in the past 30 days, and 31% reported using a multivitamin/mineral supplement.
To update its 2014 recommendations, the USPSTF reviewed the evidence for the effectiveness of supplements with dietary nutrients or multivitamins to reduce the risk of cardiovascular disease, cancer, and death in the general adult population.
Through evaluation, the USPSTF concluded that the risks of beta-carotene supplementation outweigh the benefits of preventing cardiovascular disease or cancer. He also judged that vitamin E supplementation for the prevention of cardiovascular disease and cancer had no net effect.
Six randomized clinical trials (RCTs) were conducted with beta-carotene. One of the clinical trials studied beta-carotene and vitamin A supplements. A joint analysis evaluating association with beta-carotene use showed an increased risk, although not statistically significant, for all-cause mortality associated with beta-carotene use (OR 1.06) during a follow-up period of 4 to 12 years.
A joint analysis of five studies showed a statistically significant increase in cardiovascular mortality associated with beta-carotene supplementation for 4 to 12 years (OR 1.10).
In two trials in people who smoked or had been exposed to asbestos at work, either beta-carotene supplementation alone (RR 1.18) or beta-carotene plus vitamin A supplementation was associated with a risk of lung cancer (RR 1.28).
Meanwhile, nine RCTs were conducted with respect to vitamin E. The results of the analysis showed no benefit from taking vitamin E in the composite outcome of cardiovascular events at 3 to 10 years of follow-up.
Regarding multivitamins, we took a reserved position in the sense that there is not enough evidence to judge the benefits and risks.
In an analysis of 27 RCTs of vitamin D supplementation with or without calcium, no difference was found in all-cause mortality at 6 months to 7 years of follow-up.
In addition to vitamin B, vitamin C, and selenium, the results were mixed or there was insufficient evidence to determine the effect relationship.