The appeal of popping a pill in which the powers of healthfulness are concentrated is hard to deny. And indeed, by the end of 2013, half of Americans reported taking vitamins; sales of which total at least $28 billion a year. Perhaps at play is the fact that so many of us are eating food that has had its vitality processed out of it – but eating nutritionally insipid food with a handful of vitamin supplements on the side just doesn’t work.
A growing voice of vitamin dissent reared its head in late 2013 when a panel of experts wrote a strongly worded editorial in the Annals of Internal Medicine, saying, “most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided."
New research takes this even further, finding that vitamin supplements can actually lead to increased risk of disease.
At a forum at the American Association for Cancer Research (AACR) Annual Meeting 2015 by University of Colorado Cancer Center, researcher Tim Byers, MD, MPH, describes research revealing that over-the-counter supplements may actually increase cancer risk when more than the recommended daily amount is taken.
“We are not sure why this is happening at the molecular level but evidence shows that people who take more dietary supplements than needed tend to have a higher risk of developing cancer,” explains Byers, associate director for cancer prevention and control at the CU Cancer Center.
Byers’ research started two decades ago when it was observed that those who ate more fruits and vegetables tended to have less cancer. Byers and other researchers began investigating whether or not taking extra vitamins and minerals would reduce cancer risk even further.
“When we first tested dietary supplements in animal models we found that the results were promising,” says Byers. “Eventually we were able to move on to the human populations. We studied thousands of patients for ten years who were taking dietary supplements and placebos.”
The results surprised them.
“We found that the supplements were actually not beneficial for their health. In fact, some people actually got more cancer while on the vitamins,” says Byers.
One trial looking at beta carotene supplements found that exceeding the recommended dosage increased the risk for developing both lung cancer and heart disease by 20 percent. Another trial found that folic acid, which was thought to help reduce the number of polyps in a colon, actually increased the number, according to a press statement for the study.
Byers says that people can get all the vitamins and minerals the body needs by eating healthy meals – and that many adults who take vitamins quite possibly don’t need them. And that too much can do more harm than good.
“This is not to say that people need to be afraid of taking vitamins and minerals,” he says, noting that at proper dosage multivitamins can be OK.
“But," he adds, "there is no substitute for good, nutritional food."