I’ve already summarized a study comparing low-carb to low-fat diets, now let’s look at snacks!
This study compared appetite control and satiety following high-protein vs. high fat snacks in healthy women.
Twenty pre-menopausal women were included (average age 27, BMI 23.4). Authors excluded smokers, participants with food allergies, eating disorders, diabetes, recent rapid weight loss/gain or were on any medication that would alter appetite.
Participants were randomized in a crossover design to consume one of three afternoon snacks for three consecutive days.
1. greek-style yogurt (14g protein, 25g carbs, 0g fat)
2. crackers (0g protein, 19g carbs, 9g fat)
3. chocolate (2g protein, 19g carbs, 9g fat)
On the fourth day, participants consumed a standardized breakfast meal (18%P, 61%C, 22%F), and reported to the center for testing.
During testing, they consumed a standardized lunch, followed by their respective snack (3h later).
Then, they were asked to complete scales on how much they liked the snack, and on appetite sensations every 30 minutes until they requested dinner
Post snack hunger was significantly lower at 90 minutes compared to the chocolate and cracker snacks.
Post snack fullness at 90 minutes was significantly greater than the chocolate snack, but not the crackers.
Consumption of yogurt snack delayed dinner eating by ~30 minutes compared to the chocolate snack, and ~20 minutes compare to the crackers.
Dinner intake was approximately 100kcals fewer when participants consumed the yogurt snack compared to the others.
Limitations of this study include the fact that they did not standardize or record what the participants ate during the initial 3 days along with the short time period and small sample size. Additionally, the authors used commercially available, commonly consumed snacks, to which they mention they were unable to tightly control macronutrient QUALITY (i.e chocolate had more saturated fat, simple carbs compared to the crackers).
A higher protein, greek yogurt-style afternoon snack is better for appetite control compared to chocolate and crackers!
Keep in mind that these snacks were very simple (I for one like to have a combination of macronutients for snacks, like a protein PLUS a carb or a fat – i.e. greek yogurt mixed with something). Also, it was interesting to me that post snack fullness was not significantly different between the yogurt and cracker groups. Overall, I would say if you’re just looking for something simple to snack on to keep you full until dinner (and make you eat less at dinner time!) it looks like greek yogurt is the winner here!
Citation: Ortinau LC, Hoertel HA, Douglas SM, Leidy HJ. Effects of high-protein vs. high- fat snacks on appetite control, satiety, and eating initiation in healthy women.Nutrition Journal 2014;13(1):97. doi:10.1186/1475-2891-13-97.