Throughout most of human history, our ancestors ate a diet that was nearly perfect in its balance between two essential fatty acids, omega-3s and omega-6s, which have crucial, though opposite, roles to play in metabolism.

The patient was so obese – more than 700 pounds – that it took seven nurses to turn him over. Three nurses at the New England hospital where he was in intensive care went out on workman’s compensation after injuring their shoulders and backs trying to move him.  

If you haven’t heard of it yet, get ready to grapple with the “glycemic index,” the latest wrinkle in America’s endless diet debate.

Three very fat Turkish people, all cousins, got very lucky this year, when they spent a few months in Los Angeles getting injections of leptin, the “satiety” hormone discovered in 1994 and immediately hailed as the long-awaited magic bullet to cure obesity.

In the swampy world of nutrition books, clarity and credibility are as scarce as tofu and sprouts at Dunkin’ Donuts.But clarity and credibility are precisely the reasons you should toss out your old diet books, forget the government’s famous but flawed food pyramid, and get your hands on a new book, “Eat, Drink and Be Healthy,” by Walter Willett, a nutritionist based at Harvard University.

Let’s face it: We were brainwashed. For years, nutritional gurus strummed a one-note samba: All fats are bad. And many of us played along, giving up some of our favorite foods. Like nuts.

In the early 1990s, while almost nobody was looking, the biotech industry pulled off quite a coup.

Led by industry giants like Monsanto, DuPont, Novartis and Aventis, genetic engineers began commercializing an idea they’d worked on for years – tinkering with genes to make crops more resistant to insects and herbicides.