The effect of changes in tax can be cased in terms of elasticities, where the revenue-maximizing elasticity of the tax base with respect to the tax is equal to 1. The way they talked, they seemed to expect that once the supply-side tax cut was in effect, additional revenue would start to fall, manna-like, from the heavens.
They found no difference in appetite between groups (8). Overall, I looked at 4 more studies. Two of them showed weight loss of a few pounds over a period of 8 weeks (9, 10), but the other two showed no effect (11, 12).