e life. In 2004, he died from Lou Gehrig’s disease at seventy-eight.

Walford’s death did not deter CR disciples. The CR Society claims some 3,000 members.

Positive Results, Yet Doubts Remain
So far, physiological tests on Calorie Restriction practitioners indicate that they are much healthier than the average American and may even have at least one advantage over long distance athletes. CR followers have fewer predictors of age-related diseases, lower levels of the so-called bad cholesterol and more of the good stuff, as well as lower blood pressure. One study found the dieters’ hearts functioned as if they were fifteen years younger.

Not everyone is convinced, though. Some scientists argue that such a severe diet can have harmful effects. In the study of rhesus monkeys, several died from factors that were not age-related but may have been caused by eating too little. In another experiment that tested the CR theory, the restricted diet prolonged the lives of “chubby” mice—a strain that was genetically manipulated to gain weight over their lifetime—but didn’t have any effect on lean mice. That suggests that there may be a flaw in many of the human studies that compare the CR dieters with average Americans. Since two out of every three Americans are overweight, it would be shocking if the dieters were not healthier. If they were compared to lean Americans who ate a moderate, nutritious diet, would the disparity still exist?

Lean Living
Even among diehard Calorie Restriction believers, severely limiting calories is an unsavory proposition. Scientists are working on developing other painless methods that mimic the beneficial effects of a Spartan diet. Researchers are studying resveratrol, a compound in red wine, that may trick the body into thinking it’s starving. But results so far are ambiguous. Obese mice seem to live longer on resveratrol, but lean mice don’t. Rapamycin, a drug used in organ transplants, has also boosted the life span of mice, but it suppresses the immune system, which runs the risk, paradoxically, of causing illness and death.

If these more palatable methods fail and a harsh diet proves the most promising strategy for living longer, it’s still unlikely that Americans will jump on the CR bandwagon. After all, it’s not only a hungry life, it’s potentially a very lonely one. Eating with friends and family and dining in restaurants gets stressful when counting calories is a matter of life and death. And shrunken bodies and libidos bode poorly for romantic relationships. Whether the extra years are worth the diligence and depravation might depend on how they’re spent.

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