If you’re worried about living longer, there’s one approach doctors have been a bit nervous about recommending: starving yourself to death.
For decades now, there’s been anecdotal evidence about longevity and so-called “caloric restriction” (I don’t make up such euphemisms), but until now there was no demonstration it worked in people. It certainly did in animals; mice who were kept on high-nutrition but very low-calorie diets lived longer. So did many other species.
Now a team from LSU has a paper in the Journal of the American Medical Association, showing what its authors regard as promising results. Here’s how our medical unit summarized it:
“In a randomized controlled trial, 48 overweight people were assigned either to a control group or some form of calorie restriction (as low as 890 calories per day) for 6 months. Results showed that those receiving calorie restriction not only reduced their fat mass and body weight but also reduced fasting insulin levels, body temperature and energy expenditure. According to anti-aging theories, low fasting insulin levels and body temperature are considered biomarkers of longevity, and lower energy expenditure correlates with decreased DNA damage and increased longevity.”
Intrigued? Appalled? Our medical folks polled other researchers, and got some understandably skeptical responses.
Dr. Darin Deen (Albert Einstein Medical College): “Unfortunately, this study looked at biomarkers, not at actual longevity…therefore it is hard to attach any particular significance to it.”
Dr. Keith-Thomas Ayoob (also at Einstein): “The study is just too short to draw meaningful conclusions.”
Dr. Eleftheria Maratos-Flier (Beth Israel Medical Center, Boston): “The group here was overweight. We already know that diet and weight loss are good for overweight people.”
Dr. John Messmer (Penn State): “The cynic might say, ‘Sure you may live longer, but why bother if I can’t eat?’" Other doctors weighted in similarly.
Dr. Jennifer Caudle, who often helps us with medical information, has more HERE. (Thanks to Roger Sergel, Joanna Schaffhausen and the rest of our medical unit for their research.)
We’ve done-—or considered and finally dropped-—stories about caloric restriction over the last few years, and I’ll confess that for lack of clear evidence that it was good for people, they made us uncomfortable. How might a piece affect people with eating disorders? Or was the subject irrelevant to most Americans, who would never consider keeping themselves to 900 calories a day?
The study was part of a large project called CALERIE, sponsored by the National Institute on Aging. It has studies going at LSU, Duke, Tufts, and Washington University in St. Louis. An editorial attached to today’s paper says the study will certainly get people talking. Perhaps over dinner.