Making your shake thicker can trick your brain into keeping you full for longer, new Dutch research suggests.
Researchers had 15 men try two different shakes, both on an empty stomach on different days. One shake was 100 calories and thick like pudding while another was 500 calories but thin like milk.
The researchers then measured the amount of food in the subjects’ stomachs with an MRI and surveyed them on how hungry they felt for the next hour and a half.
Even though the 500-calorie shake stayed in the subjects’ stomachs for longer, the 100-calorie shake kept them feeling as full or more full than the higher-calorie one.
That held true at their next meal, too: The researchers also gave the men an all-you-can-eat sandwich buffet, and there was no difference in how much each group ate.
There are neurons in your mouth that have a direct line to your brain, says study author and Ph.D. candidate Guido Camps. So when those neurons detect that your drink is thick, they send signals to your brain tricking it into thinking you’re getting a more substantial meal.
So if you want your protein shake to hold you over for longer, blend up your powder with high-fibre fruits and vegetables like bananas, which will thicken it, rather than mixing it with water, suggests Camps.
Other great thickeners: Chia seeds, which absorb water and create a paste-like consistency when added to liquid, and casein protein powder, which blends up thicker than whey.
In the study, Camps used a kind of fiber to thicken the shakes. You can mimic the same effect with psyllium fibre powder.
