Dr. Alia Crum

So you're going to come in, you're going to taste these milkshakes,

And we're going to measure your body's physiological response to them.

This was a within subjects design.

So it was the same people consuming two different milkshakes, two different time points separated by a week.

And at one time point, they were told that they were consuming this really high fat, high caloric milkshake.

indulgent milkshake it was like a 620 calorie super high fat and sugar the other time point they were told that it was a low fat low calorie sensible sort of diet shake in reality it was the exact same shake it was right in the middle it was like 300 calories moderate amount of fats and sugars

And we were measuring their body's gut peptide response to this shake.

And in particular, we were looking at the hormone ghrelin.

Medical experts call it the hunger hormone, rises in ghrelin, signal, you know, seek out food.

And then theoretically, in proportion to the amount of calories you consume, ghrelin levels drop, signaling to the brain, okay, you don't need to eat so much anymore.

You can stop eating and also revving up the metabolism to burn the nutrients that were just ingested.

What we found in this study was that when people thought they were consuming the high-fat, high-calorie indulgent milkshake, their ghrelin levels dropped at a three-fold rate stronger than when they thought they were consuming the sensible shake.

So essentially their bodies responded as if they had consumed more food, even though it was the exact same shake at both time points.

It was, to my knowledge, one of the first studies to show any effects of just believing that you're eating something different on your physiology.

The second piece was really important as well.

And especially for me, this was one study that really transformed the way I think about how I approach eating.

And that was the manner in which it affected our physiology was somewhat counterintuitive.

So I had gone in thinking.

The better mindset to be in when you eat is that you're eating healthy, right?

Like, you know, it just makes sense.