University of Arizona professor Cynthia Thomson is a dietician and cancer prevention expert. She’s run marathons, battled colorectal cancer and extensively studied the health benefits of the supplements she takes to encourage healthy aging.

Although her research has shown there are risks attached, she takes vitamin D and calcium supplements every day.

“I wouldn’t want cardiologists to say ‘no one should be taking calcium supplements,’ or for oncologists to say ‘everyone should be taking them’ — we really need to look at individual profiles,” Thomson told Business Insider. “I think this is where we’re going in medicine. It’s not going to be one-size-fits-all.”

Her latest study, published in the Annals of Internal Medicine, studied the effects of these supplements on more than 36,280 postmenopausal women for roughly seven years. The supplements were found to have small but positive impacts on the reduction of cancer deaths. In total, cancer-related deaths were 7% less common among the women who took the supplements over the ones given placebos.

Those who took the supplements, however, were also 6% more likely to develop cardiovascular diseases. All the same, Thomson said there are three reasons she still takes vitamin D and calcium supplements daily.

Blood test results revealed her vitamin D levels were low, her vegan-leaning diet likely lowered her calcium intake to below average levels, and her personal history of colorectal cancer trumped the risk of cardiovascular disease.

According to the dietician, choosing which supplements to take to promote healthy aging comes down to your individual lifestyle and lab results. Supplements are also not enough to guarantee a healthier life as an older adult.

“Supplements are just that — they’re intended to supplement inadequacies in a diet,” she said.