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Very small changes in behavior could have very big effect. The Lancet researchers gamed out what would happen if the average weight in the United States decreased by about 1 percent, which works out to an average weight loss of 2.2 pounds per person.

“This change might sound small,” they write, “but such a scenario would have a substantial effect on consequent health burdens.” We would avoid up to 2.4 million cases of diabetes. We would see up to 1.7 fewer cases of cardiovascular disease. As a population, we’d add 16 million more “quality life years,” a scientific measurement of both lifespan and quality of life.

How do we get there? The Lancet researchers say that, on average, it would mean each person eating 20 fewer calories each day for three years. That’s equivalent to a seventh of a can of Coca Cola or two M&Ms. That’s a pretty big health outcome for a very small amount of change.