Ponce de León Lives: The search for longer life is real science now

The scientific quest for longevity is heating up. After a century of dramatic increases in life expectancy from such things clean water systems and improved medicines and vaccines, studies are yielding important information on what produces healthy aging. Lifestyle is certainly one variable. Several high profile studies of Seventh-day Adventists who eat a vegetarian diet, don't smoke and spend a lot of time with family and church groups, routinely live to 88 or so. But exercise and diet will only get one so far and at some point genes become the predominant factor. But genes are, by definition, fixed so the real interest is in finding out what it those "longevity genes" are doing that can be mimicked by drugs.

Some of these beneficial genes appear to be involved in metabolic pathways related to growth, as well as the processing of fat and cholesterol. Kenyon manipulates a gene in her worms that reduces the action of insulin and a related hormone called IGF-1. "Lowering these hormones activates a gene called Foxo," she says, "which stimulates a whole host of responses that protect cells—boosting the immune system, increasing antioxidants, keeping proteins folded correctly." A study of Ashkenazi Jewish centenarians this year also found variations in genes governing IGF-1. A second study found protective changes in the Foxo genes of healthy 95-year-old men.

Another direction has been those studying severe low-calorie diets. Mice who eat 30 percent less live about a third longer. However replicating such studies with humans is almost impossible (though some voluntary groups are trying) and even if it was successful would people really reduce calorie intake to the levels necessary (and abide by them their entire lives)? Doubtful. But by studying why extreme low-calorie diets extend life may lead to drugs that help do the same thing. A compound from red wine called resveratrol is one being studied. Other research is on drugs that repair telomeres, the DNA caps on the ends of chromosomes. But in the end, the best advice might be from the Newsweek article covering the topic:

"According to the World Health Organization, 80 percent of heart disease and 40 percent of cancers could be prevented with a healthy diet and lifestyle," says Dr. Luigi Fontana at Washington University School of Medicine. For those of us in the wrong end of the gene pool, healthy habits may be the best life preserver around.