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The Science and the Practice of Plant-based Diets at TC

Are fat-free foods really healthier? Not necessarily, said keynote speaker Walter Willett, the Fredrick Stare Professor of Epidemiology and Nutrition and Chair of the Nutrition Department at Harvard University. He made those remarks at "Towards a Plant-based Diet: The Science and The Practice," a conference sponsored by the program in Nutrition.

Willett added that many processed foods replace fat with sugar and label it "fat-free," which is cheaper, but not always healthier. Some fats, he said, are beneficial.

The conference brought together leading scientists who study the relationship of food and nutrition to health, nutrition education and food policy scholars and community leaders who are at the forefront of promoting the transition to plant-based diets.

One of the goals of the conference was to show that eating a variety of plant foods, including whole grains, vegetables and fruits, is not only healthy, but enjoyable.

More than 300 people filled Horace Mann auditorium to attend sessions about: diet and health, cell metabolism, traditional and alternative eating patterns, biotechnology, and shifting to a plant-based diet.

A variety of speakers discussed scientific knowledge of food, nutrition, and the environment. Some of the speakers were: John Pinto, Associate Research Professor of Biochemistry in the Department of Medicine at Cornell University Medical College and Director of the Nutrition Research Lab at Sloan Kettering Cancer Center in New York City; Lawrence Kushi, Ella McCollum Vahlteich Professor of Human Nutrition; Isobel Contento, Mary Swartz Rose Professor of Nutrition and Education; Jennifer Castle, Nutritionalist from the Food Bank of Central New York; and Peter Hoffman, Chef and Owner of Savoy Restaurant.

Willett is internationally recognized as a pioneer in the field of nutritional epidemiology. He and his colleagues have ongoing studies following tens of thousands of nurses and other health professionals. These studies were among the first to note that the risk of heart disease is increased with excess trans-fatty acid intake and decreased with supplemental vitamin E intake among their other discoveries. He is also an advocate for putting trans-fatty acids on nutrition labels.

Trans-fatty acids are solid fats produced artificially by heating liquid vegetable oils in the presence of metal catalysts and hydrogen in a process called partial hydrogenation. Trans fats are produced commercially in large quantities to harden vegetable oils into shortening or margarine.

By his study's estimate, replacement of partially hydrogenated fat in the U.S. diet with natural unhydrogenated vegetable oils would prevent approximately 30,000 premature coronary deaths per year. An alternative to trans-fat is trans-free margarines that are also low in saturated fats.

He said that it is important to take into account the different types of fat in your diet. High levels of trans-fatty acid, found in fast food, can cause heart disease. Fast food restaurants use big blocks of partially hydrogenated vegetable oil because it is cheap and it can stay in the fryers for about 12 to 14 days. Willett said, "You could build buildings out of it."

Willett discussed his version of the food pyramid, which is unlike the one most people are familiar with. He said, "The current pyramid, which is the general advice given, may have little benefit and could even be harmful."

When he analyzed the current pyramid, he pointed out that using all types of fat sparingly is not healthy, some are less harmful or even beneficial. He thinks the dairy portion is too large, as increased dairy intake did not decrease bone fractures. Also, he doesn't like the way all meats are lumped together. Fish and chicken are better choices than red meat.

"Changes in diet can change risk of cardiovascular diseases and colon cancer," said Willet. "Diet can have powerful effects if you make the right food choices."

The conference also celebrated the College's 90-year-old program of nutrition by recognizing the recent appointments of Isobel Contento as the Mary Swartz Rose Professor of Nutrition and Lawrence Kushi as the Ella McCollum Vahlteich Professor of Human Nutrition.

Contento spoke about implementing a plant-based diet. It can be difficult to change children's diets. She discussed ways of making nutrition both fun and tasty for children using the classroom, family and environment. All of these components are used in the Cookshop program that gives children a more effective and hands-on lessons about food and nutrition.

Kushi talked about lessons that traditional and alternative eating patterns provide. He said that international cancer and heart disease rates differ widely and that dietary factors are probably responsible for some of that variation. Diets and lifestyles of the Mediterranean region and Japan are used as models because of their documented low disease rates. Kushi said that recent studies that examined the relationship between these foods and the risk of cancer or heart disease have discovered evidence that these dietary patterns resulted in lowered risk of these diseases.

"Examining traditional and alternative eating patterns indicate that predominantly plant-based diets are more healthful than the standard American way of eating," said Kushi.

Founded in 1909, Nutrition and Education program is one of the oldest such programs in the United States and has been a leader in integrating the findings of nutrition science, nutrition education and behavioral science to develop strategies for promoting health through dietary change in individuals and communities.

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