By David L. Brown
For some time now there’s been an assumption floating around that if you reduce your caloric intake to about 30 percent below the required daily intake you will earn yourself more years of life. I suspect a lot of people have been acting on that theory and voluntarily starving themselves in hopes of living longer. I know one such and he looks like an Auschwitz survivor.
But, sad for them, a new long-term study with monkeys has sunk that battleship. The report in the journal Nature showed no difference in life expectancy between monkeys fed a normal diet and those fed a restricted diet. An earlier monkey study at the University of Wisconsin claimed to have found a difference, but there was a flaw in that study. Unrestricted monkeys were allowed to eat as much as they wanted, thereby becoming obese. In other words, it was a study to compare simian analogues of Twiggy and Michael Moore, and therefore bore little relationship to reality.
The whole idea got started with a study of worms, which bear even less relationship to normal humans than Michael Moore, and was followed by a mouse study. But when it comes to humans, apparently the starve-yourself-old plan just doesn’t work.
Actually, it’s not surprising to me, and in fact I don’t know why they bother to mess around with monkeys because there has been an ongoing human experiment with billions of participants. It’s called real life, in which some people are consistently underfed thanks to poverty and food shortages while others eat like, well, Michael Moore. And the data from that experiment is pretty clear in squelching the idea of calorie restriction for life extension.
For example, the country of India is well-known for its large numbers of malnourished individuals. If the theory were correct, those people would be living long and prospering. Well, at least living long. But in fact, India has an average life expectancy of just 64.7 years, compared with 78.2 years for the United States. I don’t have a figure for the less-fortunate citizens of India, but my guess is that those who are better off are living longer and raising the average, so the actual results for those on the involuntarily calorie restricted diets could be lower, perhaps much lower.
There are many other places where food is scarce and people live on the edge, and indeed even lower life expectancies are observed there. The worst case scenario is the island of Mozambique, where the average life expectancy is just 34.2 years. The world average is 67.2 years and most of the Third World lies on the bottom half of the scale.
In case you’re wondering, the country that is the longest-lived is Japan with 82.6 years. Some other top-end data points include: France, known for its rich and hearty meals, 80.7 years; Switzerland, 82.1; Australia, 81.2. None of these places are known for widespread malnutrition and famine.
I think the real message to take away from all this is that extremes are bad, and of course that’s what we all kind of knew all along. People who are unusually thin have few physical resources to fall back on in case of illness. We know that young girls who suffer from eating disorders often die young and obese people are in danger of heart disease, diabetes and other debilitating diseases. So eat healthy food in normal amounts, maybe accompanied with a glass of wine or two and you’ll probably outlive all the starve-themselves-old crowd, not to mention the waddling obese.