What's that? Find out more about this peculiar phenomenom here.
In recently published work (Guido Camps, Monica Mars, Cees de Graaf, and Paul AM Smeets, Empty calories and phantom fullness: a randomized trial studying the relative effects of energy density and viscosity on gastric emptying determined by MRI and satiety?, American Journal of Clinical Nutrition 2016;104:1-8.) we have shown that fullness isn't the same as being full. Being full is less affected by how full your stomach is, but more by the the taste and feeling in your mouth of what you've eaten. This leaves us to conclude that thin liquids may leave you feeling rather empty, regardless of their caloric load (in our case a respectable 500Kcal). The opposite is true of a thick 100Kcal shake, which left the stomach quickly, but also left the drinker feeling rather fuller.
We will try to expand on these results in the future to further understand the effects of orosensory and gastric feedback on satiation and satiety.