What makes us eat a lot? A new study sheds light on protein and more

In the quest to understand the factors influencing our calorie intake, a new study delved into the crux of the matter. The results presented a blend of predictable elements and intriguing surprises.

Predictable Factors Impacting Calorie Intake:

The study reaffirmed the role of energy density, hyperpalatable foods (you know the really great tasting stuff like Flamin’ Hot Doritos) and eating rate as significant determinants of calorie intake. A food's energy density refers to the number of calories per gram of food. Hyperpalatable foods are typically highly processed, high in sugar and fat, and designed to trigger our pleasure centres. Eating rate, on the other hand, is the speed at which one consumes food.

Surprising Findings Around Protein:

The study's unexpected findings revolve around protein, an essential nutrient often associated with satiation (feeling full during meals) and satiety (feeling full between meals). Contrary to conventional wisdom, the study found that protein might not consistently contribute to these feelings of fullness.

Inside the Study:

The research involved an analysis of two studies conducted by the U.S. National Institute of Diabetes and Digestive and Kidney Diseases, involving different dietary patterns and 2,733 meals in total. The researchers examined the impact of four dietary variables: energy density, hyperpalatable content, eating rate, and protein content.

Unraveling the Protein Paradox:

Contrary to what was expected, a meal's protein content was associated with increased consumption in two of the four diets analysed. In the other two diets, protein content had a minimal impact on consumption. The study also found that in the low-carb and low-fat diets, higher protein intake at one meal was linked with higher calorie intake at the subsequent meal.

These findings contradict the widely accepted belief about the satiating effects of protein.

Possible Explanations for the Protein Paradox:

Study co-author, Kevin Hall, PhD (huge fan, if you don’t already follow his work, my unsolicited advice is that you should), offered several possibilities to explain the surprising results related to protein.

One hypothesis is that protein's effects on satiety may only kick in when consumption surpasses a certain threshold.

Another possibility is that the satiating effects of high protein intake might only occur in the context of a diet high in ultra-processed foods. Hall also speculates that the effects might manifest over a longer time scale than that investigated in the study.

Key Findings

Protein's Role: The findings of the study shouldn't drastically alter your dietary choices. While protein may not boost satiety as much as previously thought, it still plays a crucial role in muscle repair and hormone production.

Energy Density and Hyperpalatable Foods: Energy density and the presence of hyperpalatable foods significantly impact calorie consumption. Therefore, minimizing high-fat, energy-dense foods and limiting hyperpalatable snacks could be beneficial for weight management.

The Influence of Eating Rate: The study also revealed that the rate of eating has a consistent impact on calorie consumption across various diets. Hence, slower eating could be a useful strategy for weight loss, regardless of the dietary pattern. Ding ding, more cues for foundational eating habits.

Conclusion

This research reiterates some well-established determinants of calorie intake, while also challenging our understanding of protein's role in satiety. However, it's important to note that dietary choices should always be individualized and holistic, considering not only calorie intake but also nutritional balance and personal preferences.

References

Hall KD, Ayuketah A, Brychta R, Cai H, Cassimatis T, Chen KY, et al. Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake. Cell Metab. 2019 Jul 2;30(1):67–77.e3.

Hall KD, Guo J, Courville AB, Boring J, Brychta R, Chen KY, et al. Effect of a plant-based, low-fat diet versus an animal-based, ketogenic diet on ad libitum energy intake. Nat Med. 2021 Feb;27(2):344–53.