At a recent conference at Harvard, I heard a series of talks that left me cold – and hungry. The “Aging and Healthy Lifespan Conference,” focused on the latest molecular and dietary techniques to achieve life extension.
The presenters were an impressive team. Cynthia Kenyon, PhD, spoke about magical worms that live at least twice as long as their normal counterparts -- because of a gene mutation. Harvard’s David Sinclair, PhD, talked about his work in discovering that a compound from red wine grape skins increases the lifespan of yeast, roundworms, flies and mice on high fat diets. (Sinclair co-founded a company called Sirtris that is developing synthetic drugs, based on the compound, called resveratrol, to prevent or treat diseases of aging.)
What left me frowning was the fact that resveratrol’s fame stems from studies of caloric restriction.
Some time ago, researchers figured out that rats fed 30-40 percent fewer calories than control animals aged slower. Rick Weindruch, Ph.D., who also presented at the Harvard conference, showed similar anti-aging benefits because of caloric restriction in rhesus monkeys. After 20 years of dieting, Weindruch's primates are showing fewer incidences of diabetes, cancer, as well as heart and brain disease.
While we still have yet to see if these calorie-restricted monkeys actually do live longer (monkeys normally die after about 27 years), organizations like the Calorie Restriction Society are already taking the data and running -- or shall I say starving -- with it.
At the meeting, Leonard Guarente, PhD, presented a bit about how resveratrol works, targeting a family of molecules, called Sirtuins, which control aging in cells. Guarente noted that we would all prefer to find a drug that prevents or cures aging-related diseases and prolongs life rather having to deprive ourselves of food to stay young.
As he spoke, one woman from the Calorie Restriction Society took issue.
“I don’t feel deprived at all,” she said. “In fact, I’ve never felt healthier and more energetic in my life.”
How long had she been restricting?
Three months.
I guess the old adage “time will tell,” holds. Guarente and every other presenter at the conference were careful to point out that we do not understand the mechanisms by which calorie restriction works. Further, many of the benefits seen in research studies are only realized if the animals are restricted from birth. Finally, the benefits are far less robust when lean animals are calorie restricted -- as opposed to obese ones. And the jury is still out about long term effects on the immune system and resistance to infection.
In her column in the Yale Daily News, Kimberly Lauth points out the real danger. “While calorie restriction may address obesity, it also attracts people susceptible to eating disorders.”
The CR Society addresses this issue on their website, with an interesting comparison between anorexia and calorie restriction. The difference focuses mainly on psychology, for example:
- anorexia: “obsessed with the scale on your bathroom floor”
- calorie restriction: “obsessed with the scale on your kitchen counter.”
But is it really that clear cut?
Inadvertently backed by Harvard’s reputation, CR has the potential to start promoting calorie restriction, badly done, as a fountain of youth. We give people prone to eating disorders a front to hide behind. And we actually promote an eating disorder as a healthy lifestyle.
Calorie restriction could become a case of anorexia with an altered motivation -- getting younger rather than getting skinnier, a classic motivation for anorexia's onset.
When I wrote, “Lying in Weight: the Hidden Epidemic of Eating Disorders in Adult Women,” I listened to many women reaching middle age who maintained their eating disorder because they equated thinness with youth.
For now, I’m watching and waiting for the outcome of CR – and I’m eating.
Comments