Let Food Be Thy Supplements and Supplements Not Thy Food
In reviewing the literature regarding vitamin E this week, I found that most scientific papers touted its health benefits because it is the most powerful fat-based antioxidant. Many health issues, such as cancer, aging, arthritis, and cataracts, have been associated with oxidation. Vitamin E is promoted to help prevent or delay these chronic diseases linked to oxidation. And so it goes for all vitamins; only their upsides are promoted, and it is assumed that there are no downsides. Unfortunately, ample evidence shows that vitamins oftentimes don't help and can hurt, hence my belief that our nutrients should come from whole foods, not vitamins and supplements.
The Studies
A 2019 paper in the Annals of Internal Medicine concluded that dietary supplements are not associated with mortality benefits among U.S. adults after collecting data from 30,899 U.S. adults aged 20 years or older. 1 That same year, the NIH stated that after gathering data from over 27,000 individuals taking dietary supplements, they had the same risk of dying as those who got their nutrients through food. According to the researchers, taking dietary supplements did not affect mortality rates. Conversely, those who consumed enough vitamin A, vitamin K, magnesium, zinc, and copper in their food were less likely to die. The study did not find the same correlation for nutrient intake through supplements.
Lastly, and most unfortunately, the Iowa Women's Health Study monitored the supplement intake of over 38,000 women aged 55 and above for almost two decades. The study revealed that taking a multivitamin could lead to a higher chance of early mortality. 2
Healthy User Effect
Individuals who reported consuming dietary supplements were found to have higher education and income levels and lead healthier lifestyle. This included consuming more nutritious food, refraining from smoking or drinking alcohol, and maintaining a regular exercise routine. Therefore, when correcting for these confounding factors, the apparent benefits of supplementation disappear. 3 This phenomenon is called the healthy user effect, or bias, a problem in most health studies. 4
Vitamin E
Numerous clinical trials have evaluated vitamin E supplements as a preventative therapy for various chronic diseases due to their demonstrated ability to decrease oxidative stress. However, despite this, some studies have failed to show significant evidence of vitamin E's effectiveness in reducing the risk of cancer, cardiovascular disease, and overall mortality. On the other hand, taking vitamin E supplements was linked with a higher chance of developing lung cancer, particularly with lung adenocarcinoma.
Vitamin C
Many patients and doctors have hoped that consuming vitamin C, known for its antioxidant properties, could help conquer chronic illnesses like cancer or cardiovascular disease. However, in high enough doses, the antioxidant effect causes oxidation(pro-oxidation). It has been shown to have pro-oxidant effects and can cause damage by stimulating lipid peroxidation.
Vitamin A and Beta Carotene
Vitamin and its cousin beta carotene have been touted to benefit our eyes, skin, bones, and immune system. It is now clear from a few studies that supplements containing beta-carotene can lead to negative outcomes such as higher lung cancer rates and greater mortality among cigarette smokers. Additionally, Vitamin A has been known to cause birth defects. Additionally, high amounts of vitamin A can lead to an elevated risk of hip fractures.
Folic Acid
Folic acid, primarily known for preventing congenital disabilities, caused an increase in lung cancer, cancer-related mortality, and all-cause mortality in ischemic heart disease patients supplemented with it. 5
Calcium
Calcium supplements are recommended for the prevention of osteoporosis; however, a review of over 43,000 patients found that calcium supplementation increased the risk of cardiovascular disease by 15 percent in post-menopausal women. 6
Conclusion
Taking vitamin E, A, C, D, and folic acid supplements to prevent disease or cancer is ineffective and can harm health. So, limiting these supplements' consumption to those lacking the mentioned vitamins would be rational. In addition, when considering supplementation, seek professional supervision by a qualified practitioner. Finally, try to eat an unprocessed, nutrient-dense diet and track your nutrients with an app like My Fitness Pal.