Monday, April 7, 2008

A Week of Caloric Restriction - Day 1

Mice that eat less live considerably longer. (Photo by Darny)

The next experiment I'm going to expose myself to is caloric restriction, which aims to slow the aging process by limiting dietary energy intake. In essence, that means eating less to live longer.

Caloric restriction (or CR) been shown to work on a variety of species such as fruit flies, mice, rats and fish. It's been around for quite some time and has been proven in many studies (just type "caloric restriction" into Google). For example, 70 years ago it was noticed that mice whose diet was restricted in calories lived almost twice as long as mice who were allowed to feed freely. Studies on monkeys are undergoing and look promising. No conclusive human studies have been done (since they would take longer than the lifespan of the researchers to conclude), but it seems logical that it would work in humans as well.

The effects of CR become more profound as the amount of calories eaten decreases; the more you starve, the longer you live. The rats and mice are often on a 50% caloric restriction diet, which means that they are allowed to eat half the calories they would normally eat, which would be very difficult for humans. Nonetheless, beneficial effects are seen on less restrictive diets as well. The goal is also not malnutrition; rather, the idea is to eat less calories while getting all essential nutrients. Hence, CR is often also called CRAN (Caloric Restriction with Adequate Nutrition) or CRON (Caloric Restriction with Optimal Nutrition).

I haven't been able to find a reliable source that would say how much a person of my size, age and sex should eat daily to maintain the same bodyweight, so I'm going to have to base my starting calorie level on various estimates and websites. A figure I have often seen is a little over 2,000 kcal per day (and about 2,300 kcal if I've been to the gym that day), which seems reasonable.

According to the calculator at, I'm already on a 16.5 % CR diet compared to a control, but I'm going to take take a conservative approach and eat only 1750 kcal instead of the 2000 kcal or so I'm eating now.

The point of this experiment is, of course, not to prove that I'll live to be 120 years old, but to see whether it can be done. This way, you can sit back, relax, and munch on a hamburger while reading about my suffering for the sake of science. Will the hunger be unbearable? How long can I keep on going? Will I ever post back? Who knows!

So far today, I've eaten:

- a couple of brazil nuts (60 kcal)
- salmon (700 kcal) in coconut milk (280 kcal) with onion (50 kcal), zucchini (20 kcal) and olive oil (100 kcal)
- a plum (30 kcal)
- two apples (150 kcal)

That gives a total of about 1100 kcal. Good thing I got another 650 kcal left, 'cause I'm getting hungry just typing all that food.

Go to next post on this experiment

Digg Technorati Stumbleupon Reddit Blinklist Furl Yahoo

0 kommenttia:

  © Blogger template 'Perfection' by 2008

Back to TOP