Vitamin supplements are used by more than half of the country’s population in the U.S. In 2010, the U.S. supplement market share amounted to$28 billion (about RMB 170 billion). The annual sales of supplements in the UK amounted to £650 million (about RMB 6.4 billion), involving about 1/3 of the national population. The market share of nutritional supplements in China in 2011 was around 77 billion yuan. Users account for 10% of the population and are highly educated. Many people believe that, as a basic element to maintain the normal function of biological organisms, vitamins have the function of maintaining life and metabolism, but also can slow down aging, lower cholesterol, help weight loss, eliminate toxins from the body, prevent chronic diseases, and even prevent cancer. Johns Hopkins University School of Medicine researcher Edgar Miller believes that: where the nutritional status of the person, and then supplemental vitamins are not necessary, or perhaps counterproductive. But the results of numerous studies in recent years have made near-unflattering conclusions about the role of taking vitamins. 2007, the Journal of the American Medical Association published a study by multinational researchers that found a 4% increase in mortality from overdosing on vitamin E, a 7% increase in mortality from beta carotene, a 16% increase in mortality from vitamin A, and that there was no evidence that vitamin C could prolongs life. In a scientific paper published in the prestigious medical journal Annals of Internal Medicine, scientists analyzed a large, comprehensive study involving 500,000 people and concluded that taking vitamin supplements is almost invariably a waste of money with no health benefits. Three other related studies were published in the current issue of the Annals of Internal Medicine. The first study, a systematic review by the U.S. Task Force on Disease Prevention of 27 clinical studies on vitamin supplements and disease prevention, with more than 400,000 participants, confirmed that there is no evidence that vitamin supplements reduce any mortality rate or prevent cardiovascular disease or cancer. Moreover, smokers who took only beta carotene had an increased risk of lung cancer instead. Meanwhile, Harvard Medical School published a large population randomized double-blind controlled trial. They followed 5,947 people over the age of 65 for 12 years, all of whom took either a daily multivitamin or a placebo. The final conclusion was that long-term use of multivitamins had no benefit on cognitive or language skills in the elderly. In the last study, the American Heart, Lung, and Blood Diseases Institute and the Center for Alternative Medicine looked at 1,708 patients who had experienced a heart attack. These people took either a multivitamin or a placebo twice a day for up to five years, yet more than half stopped taking it, making it difficult for the authors to draw any real conclusions about the effectiveness of the vitamins. Vitamin E Supplements Researchers at Tel Aviv University in Israel, who published their study in the new issue of the U.S. journal Atherosclerosis Thrombosis and Vascular Biology, said they followed about 300,000 people from the U.S., Europe, and Israel, comparing those who took vitamin E to those who did not. The results found that the former had nearly four months fewer “quality-adjusted life years” than the latter. Previous studies have also found that vitamin E supplements not only do not prevent certain diseases, but may also conflict with cholesterol-lowering drugs. Researchers say that if you can get enough vitamin E from food, taking a supplement is unnecessary. Vitamin D A new study in New Zealand shows that vitamin D supplementation is not effective in preventing heart disease, stroke, cancer or bone fractures. Researchers from the University of Auckland in New Zealand reported in the latest issue of The Lancet Diabetes & Endocrinology that they analyzed 40 high-profile clinical trials and found that vitamin D supplementation is not necessary for healthy adults to prevent these diseases. Vitamin D is a fat-soluble vitamin important for bone, tooth and muscle health that the body can synthesize through ultraviolet light exposure to the skin or obtain from foods such as fish oil and egg yolks. In recent years, some studies have concluded that the health benefits of vitamin D supplementation have been overstated. In March 2013, British researchers surveyed 4,000 women and found that whether or not pregnant women took vitamin D supplements had no effect on the bone health of their fetuses, while a 2012 U.S. study found that vitamin D supplementation did not lower cholesterol levels in humans. Reviewing the results of all the large studies on vitamin supplements so far, scientists say the evidence is strong enough. These vitamins should not be used to prevent chronic diseases, only to treat them. We do not advocate taking vitamin supplements, especially since high doses are often harmful. Some people claim that there are many nutritional deficiencies in our diets, but the truth is that we eat too much overall, and we are usually perfectly well nourished.