blogged a while back about how caloric restriction -- eating a third fewer calories than you "should" while maintaining adequate nutrition -- extends maximum life spans in every species it's tried on. Now a biologist has found the gene responsible in mice. When food is scarce, as during caloric restriction, the gene produces a protein that turns off other genes that help store fat. The fat moves into the bloodstream and gets burned. This keeps the mice lean, youthful, and healthy into old age. Mysteriously, it also makes them less succeptible to a host of age-related illnesses such as diabetes.
Humans have the same gene.
If one could activate it without actually restricting calories, there is no reason people couldn't avoid significant aging for forty or fifty years beyond middle age. Diseases, accidents, and murder would still kill people, but you're talking about an average life expectancy of 100 or so . . . on top of the steady increase that better medicine has been providing for the last century. If one could tackle the cancer problem, we just might live to be 150.
The biologist, Leonard Guarente, believes medicine to stimulate the gene will be available in a decade. Twenty-second century, here I come! Hopefully.