Understanding what sustains us — and what sustains our world — is fundamental. It is also the subject of the Global Food+ 2021, a joint webinar series run by researchers at Boston University, Harvard, MIT, and Tufts on their current work on the intersection of agriculture, health, environment, and society. This free online series, sponsored and hosted by Harvard’s Weatherhead Center for International Affairs, kicks off Friday and runs for four consecutive Fridays, with each event featuring 10 speed talks of seven minutes each. We spoke with Walter Willett, professor of epidemiology and nutrition at the T.H. Chan School of Public Health and Harvard Medical School professor of medicine, who will give a talk on “Fine Tuning Healthy, Sustainable Diets” during the inaugural session this week.
GAZETTE: Your talk is titled “Fine Tuning Healthy, Sustainable Diets.” What does that mean?
WILLETT: Basically getting down to specifics of diets that are both healthy for people and also healthy for the planet. We know, in a big-picture way, the direction we need to go, but I thought I would talk a bit about looking into more details.
GAZETTE: Would you share some specifics?
WILLETT: Part of it is intuitive, but even when we say “Eat a more plant-based diet,” what we’ve come to realize is that not all plant foods are healthy. Dunkin Donuts and Coca-Cola are plant foods, but they’re not good for our health, even though they have a relatively small environmental footprint. We’ve created a plant-based dietary index with more-healthy plant foods, like whole grains, fruits, vegetables, nuts, legumes, and also unhealthy plant-based food, like sugar-sweetened beverages and things made from refined flour. It’s good to simplify things as much as possible, but we can’t and shouldn’t oversimplify.
GAZETTE: You’re also looking at sustainability, the health of the planet.
WILLETT: Exactly. That unhealthy plant-based diet might not be so bad for the planet because you get a lot of calories for area of land with modest environmental inputs. We need to look below the surface. Certainly moving toward a less animal-based diet is a good direction to go. But we can have a sustainable planet without everybody becoming a vegan.