Could Reducing These From Your Diet Help You Live Longer?

Scott: Doctor, you touched on calorie restriction already.  What about that is important in longevity?  Why is reducing calories equal, potentially, a longer life?

Dr. Terry Grossman: We don't exactly know why, reducing calories.  But we do know that no matter what species of animal we look at, whether it a yeast, or a fruit fly, or a mouse, they will live longer if we restrict their calories.  And then if we move closer to human beings, if we get to dogs, and monkeys and chimpanzees and apes, which are quite similar to humans, if we restrict their calories, they will live longer as well.  We haven't done any human experiments, in terms of longevity, because we haven't been doing caloric restriction long enough to know.  And humans have such a long life expectancy, we haven't been able to prove that his will work in humans or not.  But we have done some studies and we know that, for instance, in youth, there are certain genes that are turned on and certain genes that are turned off.  And as an individual ages, these things flip flop.  And these are aging genes.  Well, with caloric restriction, we know that it kind of turns back the clock, such that the genes that are turned on are more similar to a more youthful individual, etcetera.  So caloric restriction works as a very effective anti-aging and longevity strategy.  Not only do animals live longer when they take, when they do caloric restriction, they appear younger and they behave younger. 

Scott: To get the benefits of caloric restriction, what kind of numbers are you talking about?  In terms of, do you do a percentage of calories?  Do you have a number that you shoot for, between males and females?  How does that work?

Dr. Grossman: Well, you can take what number of calories you would normally eat.  And in most of the experiments, they will cut the calories by about 30 or 35 to 40 percent.  Average in the studies is about 35 percent.  So for someone who's eating say 2000 calories a day, this means dropping a third down to about 13 or 14 hundred calories a day, which would make an individual, you know, very, very, very thin.  And that's typically how it's done.

In Japan, there's a common form of grace before meals that they will say, particularly in Okinawa.  And it's three Japanese words, hara hachi bu.  Which is Japanese for 'stomach 8 parts full.'  And part of the culture in Japan and Okinawa is, get up from the table before you've really filled yourself up.  So maybe eat until you're 80 percent full, which we might say corresponds to 20 percent caloric restriction.  And in Japan, the people there, have among the highest longevity of any people on earth.  And if we looked in Japan itself, at the prefecture of Okinawa, where they tend to do more of this hara hachi bu, they have the longest life expectancy throughout all of Japan.  So there is some suggestion that doing caloric restriction, at a degree of about 20 percent, can also translate into increased longevity.

Scott:  How important is it when you're going to try caloric restriction to make sure that the calories you do get are full of nutrients.  I mean you have to make those calories count then, don't you?  Otherwise you could really be starving yourself.

Grossman:  Absolutely.  If you're gonna cut your calories... the group that practices caloric restriction are called CRON-ies.  C-R-O-N.  And what that is an abbreviation for is caloric restriction with optimal nutrition.  Because if you're going to, you know, slash your calories like that and do that every day of the week, then yeah, you could get into trouble if you're not careful to make sure that the body gets the essential vitamins, minerals, protein, fats and things like that.