Many people take vitamin supplements to better their health. A team of researchers has now found that one particular popular supplement may up cancer risk and even cause it to spread to the brain.

Nicotinamide riboside (NR) is a form of vitamin B3 that has been promoted as an anti-aging supplement. Indeed, it is known for its potential in metabolic and age-related disorders, the researchers wrote in their study, published in Biosensors and Bioelectronics. However, despite being a widely available supplement, the “understanding of NR uptake by different cells and tissues is greatly limited by the lack of noninvasive in vivo imaging tools limiting its clinical translation.”

For their work, the researchers developed and used non-invasive bioluminescent imaging to understand how NR actually works in the body. They looked at NR levels in cancer cells, T-cells and healthy tissues, the University of Missouri (MU) noted in a news release.

NR increases cellular level energy and cancer cells “feed off of” it. Study corresponding author Elena Goun, of MU, and her team analyzed the role NR plays in the “development and spread of cancer.”

The researchers found that supplementing with NR led to a “significant increase in cancer prevalence.” Further, high levels of it may not only increase the risk for triple-negative breast cancer, but also the risk of metastasizing to the brain — a point that may already be deadly since “no viable treatment options exist at this time,” Goun, whose own father had died of colon cancer, said.

“Some people take them [vitamins and supplements] because they automatically assume that vitamins and supplements only have positive health benefits, but very little is known about how they actually work,” Goun explained. “Because of this lack of knowledge, we were inspired to study the basic questions surrounding how vitamins and supplements work in the body.”

The results show the importance of looking at the potential side effects of supplements. NR, for instance, is quite widely used and available. Certain human clinical trials are even using it to “mitigate the side effects of cancer therapy,” said Goun.

“These results outline the important role of powerful nutraceuticals like NR in cancer metabolism and the need to personalize their use in certain patient populations,” the researchers wrote.

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