Over the past decade, vitamin E has become one of the top-selling supplements in the United States, in part because research released in the early- to mid-1990s suggested that taking vitamin E supplements might protect against heart disease, boost the immune system and reduce the risk of macular degeneration.
Now, however, more recent studies have failed to confirm these earlier findings, calling into question vitamin E's status as a super supplement.
Found naturally in vegetable oils, nuts, seeds, and green, leafy vegetables, vitamin E works as an antioxidant in the body, preventing and repairing damage caused by free radicals. Damage to body cells by free radicals may contribute to the development of several chronic diseases including heart disease, cancer, diabetes and age-related macular degeneration.
Evidence from preliminary studies suggested that taking vitamin E supplements provided protection from certain diseases associated with free radical damage, particularly heart disease.
However, subsequent studies have repeatedly failed to support these findings. When researchers at the Cleveland Clinic Foundation reviewed seven vitamin E studies involving more than 80,000 participants who took between 50 and 800 International Units of vitamin E daily and were followed for up to six years, no dose of vitamin E was proven to be beneficial for reducing death from cardiovascular disease. Further, a Canadian study that tracked approximately 2,500 women and 7,000 men aged 50 years or older who were given either a vitamin E supplement or a placebo found that, after five years, those taking the vitamin were no better off than those taking a placebo. In fact, supplement-takers suffered as many heart attacks, strokes and deaths from cardiovascular disease as did placebo-takers.
Vitamin E supplements also recently failed to demonstrate that they could boost immunity in older people. Researchers in the Netherlands randomly assigned 652 healthy people aged 60 or older to take a vitamin E supplement, a placebo or a multi-vitamin for 15 months. Interestingly, when people receiving the vitamin E supplement got a cold or the flu, it lasted an average of five days longer and they suffered more symptoms than the placebo-takers. In addition, a 2002 Australian study of 1,000 healthy volunteers found that those who took vitamin E supplements were no less likely to be diagnosed with macular degeneration than those who took a placebo.