Although the American public is not noticeably clamoring for a well-spoken proponent of veganism, Barnard has sold approximately 1.5 million copies of his books on various aspects of nutrition. His latest book, "Turn Off the Fat Genes," looks at how emerging genetic information is redefining the long-held suspicion that genes play a role in determining body weight.

PCRM has been a persistent thorn in the side of the U.S. Department of Agriculture. It has taken the USDA to court and successfully opened up the unlawfully concealed workings of the USDA's board selection process. Six of the 11 USDA board members have financial ties to the meat, dairy and egg industries, and PCRM maintains that these ties are more responsible for the preponderance of meat, dairy and egg products in the USDA's nutrition recommendations than sound nutritional science.

PCRM is also reaching out to incoming medical school students. Barnard has helped them abstain from or, in many cases, entirely do away with courses that require operation on a healthy animal that will subsequently be euthanized. More than half of all medical schools, including those at Harvard, Stanford, Columbia and Yale, have dropped live-animal labs altogether, thanks in part to Barnard's work. One resister, Colorado University, recently suffered through a homecoming football game in the baleful shadow of a circling plane towing a PCRM-sponsored banner that read "CU Medical School: Stop Killing Dogs!"

Nobody likes an overzealous vegan crusader, but Barnard is no tiresome zealot. His mission in practice, publication and advocacy has been to bring about a richer interpretation of the Hippocratic oath's central credo: "First, do no harm." He makes a compelling case that what's good for human health also happens to be good for animals. If current dietary habits hold, more Americans will die from heart disease than from any other single cause, he says. Vegetarians and vegans are disproportionately spared heart troubles. It is as much in our interest not to eat animals, he insists, as it is in the animals' not to be eaten.

You encourage the abolition of experimentation on animals for both ethical and practical reasons. But when a cure for some minor ailment is found after decades of research on thousands of animals, I think the general public considers that money and those animals' lives -- no matter how many thousands -- well spent.

Let me be clear about what PCRM's mission is. We promote preventative medicine, which mostly involves exercise and diet. There is abundant evidence that the healthiest diets are those that avoid animal products -- among other changes you would want to make, like avoiding fried foods. In addition, we conduct research trials and have been active in research for a long time. Like most medical organizations, our efforts and research do have an ethical foundation. Where the participants in research are human beings, we have advocated the highest ethical standards.

We have actually sued the federal government over an experiment that involved injecting short children with a genetically engineered growth hormone, which these kids did not need. We don't object to kids' getting a hormone if their bodies are not making it. But these were kids with adequate growth hormone levels, and the experimenters were trying to alter their physiology through injections, and it was fraught with danger.

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