Free Radical

As the California sun descends on an afternoon social of wine, cheese, fruit punch, and Ping-Pong, National Medal of Science-winner and University of California at Berkeley biochemist Bruce Ames extols the virtues of pesticides to a former student. Pesticides allow fruits and vegetables to be produced more cheaply, he says, which means more poor people can afford to eat them. Poor people are most at risk for cancer, heart disease, and other ailments linked to diets low in fruits and vegetables. Hence, in the world according to Ames, pesticides confer a public-health advantage that far outweighs any health risk posed by their noxious residues. "If the EPA eliminates all the pesticides," he says, "all it's going to do is increase the price of fruits and vegetables, and there will be more cancer." "Isn't he great?" the student gushes. It's a typical reaction. Time and again in the course of his career, Ames, 73, has managed to deliver unpopular and even preposterous messages without denting his own credibility. Slender and mild-mannered, favoring striped shirts and cardigans, he has the bearing of a favorite uncle at a family reunion who tells silly jokes: "When I feel like exercise, I run my experiments, I skip controls, and I jump to conclusions." His track record helps silence detractors. Ames invented a simple test in the 1960s to identify cancer-causing chemicals that is still used worldwide. He has collected top honors in his field, published more than 450 scientific papers, and become one of the most cited scientists alive. Now Ames has decided to take on the most brow-raising research of his career: a scheme for physical and mental rejuvenation that relies mostly on common dietary supplements. His research group at Berkeley and at the nearby Children's Hospital Oakland Research Institute has discovered a simple recipe that makes old rats think and act more like young ones. "If I'm lucky," Ames says, "we'll add a few years to human lives with this research." But luck is only one ingredient in Ames's success. He describes himself as a big-picture person, a so-so student who somehow made good in academia by assembling the byzantine details of other scientists' insights into coherent wholes. He never mentions hard work. Although well past the age of retirement, Ames still lives for the lab. "I told a friend that I was doing the best work of my career," he says, "and he said I had been telling him that for 30 years."