Web edition: April 20, 2009
You’ve been reading about it in Science News and elsewhere for years: how you can live longer and healthier by cutting back on calories. Way, way back. And for much of the rest of your life.
Which of course begs the question: Is living longer worth the price of spending it in perpetual dietary misery?
Well, maybe we won’t have to. At the Experimental Biology meeting here in New Orleans, this week, researchers from a group of collaborating institutions reported progress toward a more palatable alternative. They describe a dietary supplement that elicits biochemical changes characteristic of calorie restriction — without having to cut any actual calories.
Apparently, work on such agents has been underway for more than a decade. The first candidate, 2-deoxyglucose showed promise. Like true calorie restriction, it could reduce pulse and heart rate, limit the development of tumors, protect the nervous system, and more. However, reports George Roth of GeroScience in Pylesville, Md., and his colleagues, this 2-DG “had a narrow window between effective and toxic doses.” Oops, that could be a little problematic.
So Roth and his team (from P&G Pet Care, Wayne State University, Southern Illinois University and the Pennington Biomedical Research Institute) have been mining avocados for an alternative — MH (for mannoheptulose). It’s a fairly simple sugar with a 7-carbon backbone.
When fed to mice in fairly concentrated doses (roughly 300 milligrams per kilogram of an animal’s body weight), it improved insulin sensitivity and the clearance of glucose from the blood. Meaning it helped overcome diabetes-like impairments to blood-sugar control. MH supplementation also improved the ability of insulin, a hormone, to get cells throughout the body to do its bidding (and that’s a good thing).
MH revved up the burning of fats in muscle. That’s the opposite of fat deposition and something that these scientists note “would be an expected effect of a calorie restriction mimetic.”
Treated mice also lived longer — some 30 percent longer than untreated animals. And they were happier, I’m guessing, because they didn’t have to give up most of their chow to achieve this life extension. Indeed, their food intake and weight matched that of untreated mice.
Now this appears to be science in the interests of foodies everywhere.
Roth, G., et al. 2009. Mannoheptulose Glycolytic Inhibitor and Novel Caloric Restriction Mimetic (Abst. 553.1). Experimental Biology 2009, New Orleans (April 19).