Kelly Brownell shifted focus in the late 1980s/early 1990s to question the negative effects of yo-yo dieting and the potential harm of obesity treatment.

“he had a change in the I guess this would have been the very late 80s early 90s he uh shortly there after switched to Yale uh he got the MacArthur prize the so-called genius award and he started to look at maybe concerns about the negative effects of obesity and he was one of the most powerful not the first but one of the most powerful voices to start raising questions about the effects of yo-yo dieting or weight cycling going up and down are we doing more harm than good are we just building false hopes up for people because obesity treatment is useless”