by | Apr 22, 2015 | Diet and Cancer

Overconsumption of Vitamins and Supplements Increases Risk of Cancer

A review of 20-years of research by a prominent cancer center finds that people who take more than the recommended dosage of vitamins and supplements are at a greater risk for the disease.

Dr. Tim Byers, associate director for cancer prevention and control at the University of Colorado Cancer Center, made the statements at the 2015 annual meeting of the American Association for Cancer Research in Philadelphia.

“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,” Byers said in a statement released by the agency.

Center spokeswoman Erika Matich told the N. Y. Daily News, Byers made the comments after a review of current research of the past two decades. Byers has not released a new report specifically on this topic.

Matich stressed that these health products are safe as long as consumers do not exceed the recommended amounts.

At the end of the day we have discovered that taking extra vitamins and minerals do more harm than good.

“The best way to get the nutrients you need is to eat them in real foods with a balanced diet,” she said. “More doesn’t make it better. Take the recommended dosage.”

Byers started to examine the benefits of these supplements 20 years ago.

Doctors had begun to notice people who eat more fruits and vegetables had a lower risk of the serious illness and he wanted to see if there were similar results with these health products.

And after studying thousands of patients over the past decade they discovered more people taking the vitamins got cancer than people taking placebos.

“We found that the supplements were actually not beneficial for their health,” Byers said.

The products are often marketed as ways to lower the risk of the disease but people should get their nutrients with a balanced diet.

Some examples include people who took excessive amounts of beta carotene supplements, which produce Vitamin A and help improve peoples’ immune system and vision, increased the risk for developing both lung cancer and heart disease by 20 percent.

A 2005 study of French women found that the number of smokers with high beta-carotene intake who had cancer (368.3 per 10,000 women) more than doubled compared to women with low levels of the supplement (174 per 10,000 women), reports Medical News Today.

People who have taken too much folic acid have also reported an increase of colon polyps, which forms stacks of cells in the lining of a colon and can develop into colon cancer.

In a 2012 article Byers co-wrote with four colleagues, the experts argued the products should not be labeled for cancer prevention unless there is proven results from a clinical trial. They note that many of the manufacturers market their product as a way to reduce their chances for cancer.

The best way to get the nutrients you need is to eat them in real foods with a balanced diet.

“In considering the current evidence, many expert committees and organizations have made public health recommendations, generally concluding that nutritional supplements have little to no benefit in preventing cancer,” the report states.

“Perhaps, it is generally assumed by supplement users that these products are as well regulated as over-the-counter medications. These beliefs underscore the need for efforts by scientists and government officials to encourage the public to make prudent decisions based on sound evidence with respect to use of dietary supplements for cancer prevention.”

Byers adds many people taking these supplements may not need them if they eat a healthy, balanced diet.

“At the end of the day we have discovered that taking extra vitamins and minerals do more harm than good,” he said.