Vitamin E refers to a group of fat-soluble nutrients known as tocopherols and tocotrienols. Alpha-tocopherol is the most active form of vitamin E in the body, and functions to promote the immune system, muscle growth, healthy eyes and skin, as well as a number of other metabolic processes. Vitamin E is also an antioxidant, a substance that lowers the production of free radicals or reactive oxygen species (ROS). Nuts, leafy green vegetables, avocado, canola oil, and flaxseed oil all have high levels of vitamin E.
A genetic variant in the APOA5 gene is linked to vitamin E levels, particularly the alpha-tocopherol form. This gene encodes an apolipoprotein necessary to regulate the levels of triglycerides, or storage fats. Individuals who inherit the protective genetic variant of APOA5 have higher levels of alpha-tocopherol and a lower risk of vitamin E deficiency.