Research has shown the potential health benefits of bioactive nutrients — those compounds found in foods like fruits, vegetables, tea, and cocoa. And consumers are showing an increased interest in learning more.

But can there be too much of a good thing?

John Erdman, a professor emeritus in the Department of Food Science and Human Nutrition at the University of Illinois, and his lab have studied bioactives and their health benefits for years. Now, Erdman and a team of other scientists want to see recommended maximum intake levels established by public health officials in order to help educate people about what they should be consuming. Such guidelines are needed whether bioactive nutrients are consumed from fruits or vegetables as part of a healthy diet, or from supplements derived from those foods.

In a series of recently published papers, including a study in the journal Regulatory Toxicology and Pharmacology, Erdman and colleagues report that the key to establishing appropriate levels is assessing bioactives’ safety and potential toxicity: In other words, how much is too much before there are adverse side effects?

“There’s been a huge amount of interest in bioactives in foods, not only in the College of ACES at Illinois, but around the world, as they relate to cancer, heart disease, diabetes, and longevity. Often times we’ll use an animal model or cell culture model to test a bioactive to see if it has efficacy. I don’t think very many people think about the safety side, though,” he adds, pointing out that even life-essential things like water or oxygen, can be toxic if too much is taken in.

read more

Dr. Stegall’s Comments: It is tempting to assume that more is better, especially when dealing with natural treatments such as foods and nutritional supplements. I always stress to my patients that any substance – natural or manmade – which has a potential effect in the body also has the potential for side effects and toxicity. The notion that “natural” treatments have a magical combination of effectiveness without any toxicity potential is, to be honest, magical thinking. It isn’t true. We must use discretion with all of our treatments, with a goal of balancing effectiveness and safety.