Vitamin E (α-Tocopherol): Emerging Clinical Role and Adverse Risks of Supplementation in Adults

Abstract

Vitamin E, primarily in its active form α-tocopherol, is a well-known antioxidant that protects cells from oxidative stress and free radical damage. It plays an essential role in maintaining cellular integrity and supporting immune function, making Vitamin E a widely popular and easily accessible dietary supplement for overall health and wellness. However, high-dose Vitamin E supplementation has become a concern related to potential risks. The scientific research surrounding the safety and efficacy of Vitamin E is complex yet emphasizes a balance in the use of Vitamin E supplementation. Excessive or high-dose supplementation causes a shift in this balance, as Vitamin E's beneficial antioxidant properties are outweighed by harmful interference in normal cellular processes such as immunity, cell growth, and oxidative stress. An additional complication involves Vitamin E's anticoagulant effects, which have been shown to amplify the risk of bleeding when high-dose supplementation is combined with blood thinners such as warfarin and aspirin. Studies have linked high-dose Vitamin E supplementation to adverse outcomes, including enhanced risks of all-cause mortality, hemorrhagic stroke, cardiovascular events, and certain cancers. These risks are particularly significant for individuals with pre-existing health conditions such as heart failure, coagulation disorders, or a history of stroke. The potential risk of adverse side effects emphasizes the need for further research into high-dose Vitamin E supplementation. This review will provide a comprehensive analysis of Vitamin E's multifaceted role in health and physiology, focusing on navigating the balance between potential benefits and risks in supplementation.

Keywords: antioxidant; cancer; cardiovascular; hemorrhage; stroke; vitamin e; α-tocopherol.