by Jennifer Nault
Remember the nineties, when the phrase ‘trans fat’ suddenly emerged as a public health menace? Whatever happened to those insidious heart-clogging unsaturated fats? Walter Willett happened to them.
With his determined, evidence-based approach to righting nutritional wrongs, Willett, the most recent winner of McGill’s Bloomberg Manulife Prize for the Promotion of Active Health, led a team of researchers at the Harvard School of Public Health who played a pivotal role in phasing out an industry standard that was contributing to thousands of deaths from heart disease every year.
Willett and his colleagues spearheaded the regulatory listing of trans fats on food labels, and, not surprisingly, their use dramatically declined. This past November, the FDA announced that trans fats are being moved out of the ‘generally recognized as safe’ category – a final victory for Willett and the researchers who first sounded the alarm back when high-protein, low-carbohydrate diets were just beginning to emerge. Back then, people were making high-risk food choices bolstered by an assurance that fat was the answer, while making no distinction between ‘good’ fats and ‘bad’ fats.
The world’s most cited nutritionist, Willett, a tall, lanky, snow-white mustached Midwesterner, is an epidemiologist and the longstanding chair of Harvard University’s Department of Nutrition. He is widely considered to be among the top experts in making connections between diet and disease.
Willett, who recently presented a sold-out lecture at McGill, has recently turned his attention to one of our most firmly entrenched beliefs around food, the nutritional supremacy of milk. “Drinking milk is not essential for good health,” he says over a cup of coffee – black. “I’m looking at the data, and the main justification for consuming high quantities of dairy – we’re told – is to prevent osteoporosis and fractures, but that is just not supported by scientific evidence.
“Dairy is right out in front of [Canada’s Food Guide], like it is in the U.S., but maybe more so,” says Willett. “It’s interesting and complex because many people grow up believing milk is vital to good health.
“But if you go out into the world, you will see that the highest dairy consuming countries also have the highest fracture rates. Most of the world does not consume dairy products past their early years. This link between high dairy consumption and higher rates of fractures, well, it’s been a real puzzle. One significant reason is that high dairy consumption makes you grow taller, and being tall puts us at higher risk of fractures. It’s just the mechanics – a long stick is easier to break than a short stick.”
At nearly 6’3, Willett is clearly not skewing the results in his favour.
Inundated by media attention after winning the Bloomberg Manulife Prize, Willett was touted as the ‘Dr. Oz’ of nutrition, but the comparison is fleeting, at best. He’s no grandstander, and one gets the sense in talking to him that he’d much prefer to stand aside and let the evidence speak for itself.
“Anybody, no matter what their qualifications, can go on the web and make pronouncements,” he says. “Commercial interests can make huge claims to sell their products… What we really needed was a body of empirical evidence that could, by itself, guide us.”
For more than 35 years, Willett has been using epidemiologic approaches to investigate the cause and prevention of cardiovascular disease, cancer, and other conditions. He and his team of researchers tracked 121,700 people through the large-scale Nurses’ Health Study, with 90 percent of the subjects still participating. The research found positive associations between alcohol consumption and breast cancer, as well as animal fat and red meat consumption and the risk of colon cancer, along with other diet-related connections to diabetes, cataracts, glaucoma and gallstones.
Willett doesn’t think we always know what’s good for us. “A lot of the times, the healthier products – marketed as organic or vegetarian – are loaded with sodium to enhance the flavour,” he says. “I understand why people say they’re confused. We need a healthy sense of skepticism, and part of my reason for writing the book Eat, Drink, and Be Healthy was to bring together the best available evidence in one place.”
Fortunately, many of the issues causing confusion are being addressed, he says, and we now have more tools available to make the right choices. “The FDA is currently working on simplified scoring for labels that would go on the front of food packages – something like a health score from 1 to 100 – they’re working on that and also on improving the nutrition labelling itself,” he says.
If all else fails, we can always follow Willett’s own diet: “Personally, I follow the Mediterranean diet. They weren’t just smart; these are the foods that were – fortuitously – locally available to them. Now if you read Hippocrates, you will find he had some eating suggestions and ideas about moderation that were quite consistent with what we need today.”
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