Vitamins and minerals are essential for good health, but it is possible to take too much. Just like eating too much sugar or drinking excessive amounts of water, taking too many supplements can be hazardous to your health. According to Johanna Dwyer, DSC, RD, senior nutrition scientist in the Office of Dietary Supplements of the National Institutes of Health and professor of medicine (nutrition) and community health at the Tufts University School of Medicine, vitamin D, calcium and folic acid are three nutrients that can be consumed in excess, particularly through supplements. It is well known that people who eat a lot of vitamin and mineral-rich foods tend to live longer and healthier lives.
However, taking too much of a vitamin can lead to serious health issues. For example, while vitamin A helps keep vision and immune system healthy, its toxicity can cause hair loss, bone loss, confusion and even liver failure. Similarly, while vitamin C is unlikely to cause toxicity in healthy people, it can cause tissue damage and fatal heart defects in those with hemochromatosis, an iron storage disorder. Additionally, a recent study published in the Journal of the American Heart Association found that calcium supplements may increase the risk of plaque building up in the arteries and causing heart damage.
Consumers are often bombarded with health information that tells them that taking high doses of certain vitamins can benefit their health in many ways. However, some studies show no evidence that many popular supplements have real health benefits, leading many scientists to change their recommendations. Science shows that taking a lot of supplements does not seem to have real health benefits and could even be harmful. People with health problems can experience even more serious reactions when taking too much of a vitamin.
According to the National Institutes of Health, taking high doses of vitamin C can cause stomach cramps and diarrhea. It is not about taking one large dose of a supplement occasionally; rather it is about taking an excessive amount on a consistent basis, even if it is something like calcium which is key for good health. Data from the National Health and Nutrition Examination Survey (NHANES) indicate that people may continue to consume supplements despite this knowledge. It is important to talk to your healthcare provider about the supplements you take on a regular basis, especially if you have a health problem, dietary restriction or are taking any type of medication.
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