A new study published in the American Journal of Clinical Nutrition showed that consuming certain types of milkshakes helps people stay satiated between breakfast and lunch, leading to a lower caloric intake throughout the day.
In other words, milkshakes may actually help you lose weight.
To conduct the study, researchers from Wageningen University in the Netherlands started with a group of 15 men with a mean BMI of 22.6 (A BMI of 18.5 to 24 is generally considered healthy). After breakfast, each man drank a dairy-based milkshake that varied in calories and thickness—some milkshakes were just 100 calories, some were 500—others were super runny, while others were thick and creamy. All of the shakes had the same nutritional profile breakdown with 50 percent carbs, 20 percent protein and 30 percent fat.
After gulping down the shakes, participants got MRI scans to determine how quickly their stomachs emptied after consuming the drinks and each man self-reported his own appetite level. Then they were given lunch and told to eat until they felt full.
The stomachs of the men who drank the thin, low calorie shakes emptied the fastest,with the liquid on average traveling from the stomach to the small intestines in just 26.5 minutes. But the men who drank the thick, high-calorie shakes had much slower gastric emptying times—almost 82 minutes.
But men who drank thicker, 100-calorie milkshake reported greater feelings of fullness than those who consumed a thin 500-calorie shake-- even though the gastric emptying time for thicker, low-calorie shake was slightly less than the thin high calorie version.
"The increase in perceived fullness that is due solely to the increased viscosity, which is a phenomenon that we refer to as phantom fullness, may be useful in lowering energy intake," wrote the study authors.
Phantom fullness isn’t a new phenomenon. And it has nothing to do with the upcoming “Ghostbusters” remake. Volumetrics is the idea that eating high-volume, low-calorie foods gives dieters more mileage for their money and leads to longer lasting feelings of fullness.
The milkshakes in the study were thickened using locust bean paste—not extra ice cream, so it's not an excuse to binge on Baskin Robbins. But leader study author Guido Camps told Mic via email that you can easily thicken up a smoothie or shake with fibers like guar gum and carb-based xatham gum to “add viscosity to a smoothie, making it thicker without adding calories.”
In the case of the milkshakes, the super dense, but really low-calories milkshakes could be the key to staving off hunger and preventing overeating later in the day. But the study authors say more trials need to be conducted to prove it.