"It is not that these nutrients are toxic – they are essential and we need them, but we need them in a certain balance," says Doctor Tim Byers of the University of Colorado Cancer Centre.
Byers says that discusses the clinical and policy implications of the increased cancer risk from high dose dietary supplements.
"We have a window into less than half of the biology of what these nutrients are doing," Byers says. "We say generalised things about them, calling them an antioxidant or an essential mineral, but true biology turns out to be more complex than that. The effects of these supplements are certainly not limited to the label we give them. And, as we've seen, sometimes the unintended effects include increased cancer risk."
Currently the FDA regulates dietary supplements as food, but, as Byers and colleagues suggest, supplements, especially at high doses, are more accurately described as inhabiting a mid-ground between food and drugs. Like drugs, supplement ingredients are biologically active – sometimes for better and sometimes for worse.
"We need to do a better job as a society in ensuring that the messages people get about value versus risk is accurate for nutritional supplements," Byers says. "My conclusion is that taking high doses of any particular nutrient is more likely to be a bad thing than a good thing."
MEDICA.de; Source: University of Colorado