In Brief

Animals left to choose their own proportions of nutrients appear to stay healthier if they develop diabetes, according to a new study in the October Behavioral Neuroscience (Vol. 121, No. 5). Rats allowed to choose their own diet both before and after they were artificially induced to develop diabetes had less severe symptoms than similarly treated rats that were given standard chow or a custom chow with nutrients in the same ratios as ready-made chow.

What's more, the self-selecting rats with diabetes ate and drank less, were more impervious to pain, and had lower blood sugar than members of both control groups, according to the study conducted by Tufts University researchers Monica Leibovici, PhD, and Robin Kanarek, PhD.

The results suggest that the right type of diet can decrease the severity of diabetes, but only if undertaken prior to disease onset. What type of diet? The healthier rats ate more protein and fat and fewer carbohydrates than are typical in rat chow.

That's not surprising, given that protein is known to ease diabetes symptoms and lower carbs curb demands on the pancreas. Still, the authors stress that the "overall pattern of nutrient choice was beneficial" by giving the rats the most protective ratio of protein to fats and carbohydrates.

Finding that balance might be harder for humans. Kanarek speculates that, "for most of us, the availability of highly palatable, highly caloric foods may be overriding our ability to select a healthy diet."

-R. Adelson