Calorie Restriction May Not Extend Lifespan

sciencehabit writes "Slash your food intake and you can live dramatically longer — at least if you're a mouse or a nematode. But a major study designed to determine whether this regimen, known as caloric restriction, works in primates suggests that it improves monkeys' health but doesn't extend their lives. Researchers not involved with the new paper say the results are still encouraging. Although the monkeys didn't evince an increase in life span, both studies show a major improvement in 'health span,' or the amount of time before age-related diseases set in. 'I certainly wouldn't give up on calorie restriction as a health promoter' based on these findings, says molecular biologist Leonard Guarente of the Massachusetts Institute of Technology in Cambridge."

Comments

intermittent fasting

[rfischer]

It might turn out that it's not caloric restriction that's important, but periodic fasting.

There is research showing that even if you keep your overall food intake (and body weight) constant, but **fast on alternate days**, you can improve blood glucose and insulin levels

Check it:
http://www.pnas.org/content/100/10/6216.full

Re:Misleading

[crmarvin42]

Very True! Wish I had mod points.

There are two longitudinal monkey trials on calorie restriction, and they differ in what exactly the CR diet is compared to. One is verses a diet formulated to meet, but not exceed maintenance energy requirement, but the other is versus free-choice (which allows over eating). The first (the one cited above) shows no benefit, but the other shows remarkable benefit. Seems clear to me that it's the over eating that shortens life, not restriction that elongates it, at least in Rhesus monkeys.

Fat is more energy dense than starch, but it is also more energy intensive to absorb and transport in the body. Starch is absorbed almost energy free, but fat needs to be broken down every time it crosses a membrane and that takes energy. However, I've seen some pretty fat pigs in research trials as a result of feeding 30% fat (oil, lard, choice white grease, etc.) in the diet. So it CAN be done, but who really wants to essentially be drinking bacon grease.

-A Nutritionist