Vitamin Overdose Can Lead to Cancer, Study Finds



Although research about the effectiveness of dietary supplements, or vitamins, is still not conclusive, many people create daily vitamin regimens in the hope that the practice will improve their health and help prevent illness.

A new study, however, presented at the American Association for Cancer Research Annual Meeting 2015, has found that too many vitamins can actually lead to heart disease and cancer.

Dr. Tim Byers, of the University of Colorado Cancer Center, remarked about the research he carried out, “Evidence shows that people who take more dietary supplements than needed tend to have a higher risk of developing cancer.”

Although the initial test results in lab animals were promising, Byers said: “We studied thousands of [human] patients for ten years who were taking dietary supplements and placebos…We found that the supplements were actually not beneficial for their health…In fact, some people actually got more cancer while on the vitamins.”

Specifically, a trial involving beta-carotene supplements found that over-dosage lead to a 20% increase in the risk for developing cancer of the lungs or heart.

Similarly, supplements like folic acid had opposite and detrimental effects when taken in high doses.

Dr. Byers makes sure to add that people should not be afraid of taking vitamins. “If taken at the correct dosage, multivitamins can be good for you…But there is no substitute for good, nutritional food.”

Vitamins and dietary supplements are an extremely lucrative business. The Council for Responsible Nutrition, the trade association for American dietary supplements, countered Dr. Byers findings. “Cancer is a multifactorial disease for which there is no proven prevention…Government research demonstrates that Americans do not obtain all the nutrients they need from food alone, and in those cases, dietary supplements can help fill nutrient gaps…We do not recommend high doses of vitamins, unless under the direction of your doctor.”