Mind Over Milkshakes: How Your Mindset Guides Physical Response to Food

Can your mind fool your physiology into believing you’ve either eaten something very healthy—or done the opposite? A study from Columbia Business School postdoctoral research scholar Alia Crum says yes.

Crum set out to test whether physiological satiation, as measured by the “hunger hormone” ghrelin, varies according to the mindset with which one approaches food consumption. When ghrelin levels rise in the stomach, the brain is cued to seek food, and metabolism slows. After ghrelin levels rise and you eat a large meal, your ghrelin levels drop, signaling satiety and boosting metabolism.

The study abstract explains that on two separate occasions, 46 participants consumed the same 380-calorie milkshake under the guise that it was either a very “indulgent” 620-calorie concoction or a “sensible” 140-calorie shake. Ghrelin was measured via intravenous blood samples at three time markers: baseline (20 min); anticipation (60 minutes); and post-consumption (90 minutes). During the first interval (between 20 and 60 minutes), participants were asked to view and rate the (misleading) label of the milkshake. During the second interval (between 60 and 90 minutes), they were asked to drink and rate the shake.

The mindset of indulgence produced a dramatically steeper decline in ghrelin after subjects consumed the shake, whereas the mindset of sensibility produced a relatively flat ghrelin response. Satiety was consistent with what participants believed they were consuming rather than with the actual nutritional value of the food they’d consumed.