“Our results do not support the idea that high protein or high fibre pasta produces a greater satiety response compared to pasta with lower amounts of either nutrient. It is likely that since pasta is already a very satiating food, the subjects were unable to differentiate between the three conditions," they wrote in the Journal of Food Science.
“These results build upon previous research to show that it is challenging to find differences in satiety with a population that is comprised of healthy, normal weight men and women.”
The researchers suggest that while protein and fibre are thought to be satiating nutrients, an increased amount of each macronutrient may need to be consumed in order to illicit a change in satiety.
The participants rated the high protein pasta “less tasty and less pleasant” than the other two pastas.
The study
The team of researchers recruited 36 healthy men and women to participate in the randomised, double-blind crossover trial.
They gave participants one of three types of pasta that were all prepared in the same way and served with a standard tomato sauce - high protein pasta
(16 g protein, 6 g fibre), high fibre pasta (11 g protein, 8 g fibre) or control pasta (11 g protein, 6 g fibre). Quantities were calorie-controlled and participants were given 500 ml of water to drink.
Participants rated how full they felt using a questionnaire and also evaluated the palatability and pleasantness of each pasta through a questionnaire, as well as measuring gastrointestinal tolerance through parameters such as discomfort, reflux and constipation.
The scientists then measured the amount of calories consumed during a snack break three hours later where participants were told they could eat as many snacks (trail mix, granola bars, beef jerky, chips and cookies) as they liked.
They found no significant differences between the pastas for visual appeal, smell or aftertaste but participants rated the high protein pasta less in terms of taste and pleasantness.
The authors acknowledge some weaknesses in their study design, however, such as the fact that subjects were able to eat their own breakfast, which was not standardised by the scientists.
Nor did they did screen participants for being habitual high protein consumers, which could have limited their ability to detect differences in satiety for the high protein pasta.
“The results from this research demonstrate how challenging it can be to find significant differences in satiety when attributing the effect to nutrients like protein and fibre found within a whole food matrix,” they wrote.
Source: Journal of Food Science
“High Protein Pasta is Not More Satiating than High Fibre Pasta at a Lunch Meal, Nor Does it Decrease Mid-Afternoon Snacking in Healthy Men and Women”
First published online: 29 July 2016, DOI: 10.1111/1750-3841.13406
Authors: Renee Korczak, Derek Timm, Rylee Ahnen et al.