Drexel study finds consuming 8 grams of protein – the amount found in a glass of milk – can reduce overeating of ultra-processed, high sugar and fat foods.
Researchers from Drexel University’s College of Nursing and Health Professions are exploring ways for you to have your cake and eat it too – in moderation. Published earlier this year in Nutrients, a new study found that consuming eight grams of protein 20 minutes before snacking could reduce intake of ultra-processed, high sugar and fat, low-protein foods, like ice cream.
“It’s a common phenomenon in the commercial food world that we tend to say that people are overeating foods because they’re high in sugar, fat and salt,” said Jennifer Nasser, PhD, an associate professor in the Department of Nutrition Sciences in the college and lead author of the study. “We were taking another look at these – what we call ultra-processed foods – to say, well, what’s the potential effect on consumption of not having a large amount of protein in them?”
Nasser and co-authors examined what could be done within the framework of normal eating habits, so that results could give people more control over their caloric intake while preserving the pleasure they get from food.
“From my perspective, rather than saying well you really should only eat fruits and vegetables and lean protein, etc. I follow dietary guidelines; I’m a dietician. But every now and then you want to treat. Even if it’s once a day,” said Nasser. “So, how can I sort of have my cake and eat it too? How can I be happy or satisfied and rewarded with a lower amount of caloric intake of these highly tasty foods that we all like to eat?”
The research team noted that it’s well accepted that protein, out of all of the food components, gives people the most satiety – meaning that one stops eating food sooner when eating protein. Those protein studies typically have participants eat protein and then wait one to four hours to see what the effect is of protein on when the participants start eating again.
The research team created their study to mimic an everyday eating pattern by having study participants not eat for three hours before coming to the lab — because three hours is the average eating interval of adults in the U.S. They then gave participants protein and had them consume food again in a very close proximity of 20 minutes – trying to mimic what people could do in a normal eating episode.
At the lab, participants drank eight ounces – about a glass – of a commercially available chocolate flavored, dairy-based beverage that is low in protein (only 1.2 grams per hundred calories).
“The reason we picked the commercially available, dairy-based beverage is if you look at most of these foods that we like to eat or overeat, whether it’s savory chips or sweet things like cookies or even ice cream, most of those foods only have about one to two grams of protein per hundred grams serving,” said Nasser.
On a separate day in the lab, they had participants drink a glass of nonfat milk with added chocolate flavoring. Each time in the lab after consuming the drinks, participants waited 20 minutes and then they had access to vanilla ice cream, which they could eat as much as they wanted to for a 10-minute period.
“We had 30 out of the 50 individuals who participated in the study eat less ice cream after they had consumed the nonfat milk than they did when they consumed the commercially available, dairy-based beverage that only had a little bit of protein in it,” said Nasser.
So, the next time you reach for cookies as a snack, maybe have them alongside a glass of milk, instead of by themselves.
“That would be my conclusion, subject to re-verification,” said Nasser. “I always say, as a scientist, that I like to see a study reproduced at least one more time.”
In addition to verification of the study, Nasser explained the potential for other studies to follow.
First, while the study did take self-reported physical activity into account, Nasser thinks there is potential for a study that includes objective measurement of physical activity.
“I think the physical activity findings are very interesting,” said Nasser. “I didn’t predict that we would see a differential effect of physical activity based on how participants responded to protein, but I would say that those results really need to be confirmed by measured activity before we know for sure how strong they are. And there are big questions out there as to what’s the effect of exercise on food intake, is it immediate, or is it long term exercise that affects food intake?”
Nasser is also interested in how much protein is needed to affect caloric intake, as well as the timing of protein intake in relation to the high sugar and fat snack consumption. Could it be more than two grams of protein, but less than eight? Could the protein be consumed along with the high sugar and fat snack and still impact the caloric intake?
Nasser and her co-authors have additional results from this study still being analyzed. They measured the participants’ brain activity with functional near-infrared spectroscopy (fNIRS), that was developed at Drexel’s School of Biomedical Engineering, Science and Health Systems. Nasser and Hasan Ayaz, PhD, an associate professor in the school, hope to have it published in the near future.
Media interested in speaking with Nasser should contact Annie Korp, news manager, at 215-571-4244 or amk522@drexel.edu.