The deskers ate five candies/day more than the six-footers, which the scientists calculated would correspond to a weight gain of over 10 pounds more per year.

That makes the researchers sound pretty silly. Did they just multiply the calories by the number of days worked? More likely: the candies partially spoiled their appetite at lunch, causing them to take 3 fewer bites of the cookies they packed. Or whatever. People tend to maintain stable weights over long periods of time. That implies weight isn't that sensitive to minor changes in environment, or it would fluctuate wildly.