Protein appetite as an integrator in the obesity system: the protein leverage hypothesis

Abstract

Despite the large volume and extensive range of obesity research, there is substantial disagreement on the causes and effective preventative strategies. We suggest the field will benefit from greater emphasis on integrative approaches that examine how various potential contributors interact, rather than regarding them as competing explanations. We demonstrate the application of nutritional geometry, a multi-nutrient integrative framework developed in the ecological sciences, to obesity research. Such studies have shown that humans, like many other species, regulate protein intake more strongly than other dietary components, and consequently if dietary protein is diluted there is a compensatory increase in food intake—a process called protein leverage. The protein leverage hypothesis (PLH) proposes that the dilution of protein in modern food supplies by fat and carbohydrate-rich highly processed foods has resulted in increased energy intake through protein leverage. We present evidence for the PLH from a variety of sources (mechanistic, experimental and observational), and show that this mechanism is compatible with many other findings and theories in obesity research. This article is part of a discussion meeting issue ‘Causes of obesity: theories, conjectures and evidence (Part II)’.

Type and timing of ultra‐processed foods consumption and its association with dietary intake and physical activity in women with obesity living in poverty

“…This hypothesis postulates that, among macronutrients, protein plays the most substantial role in controlling food intake; therefore, diets with a lower percentage of protein would lead to a compensatory increase in total energy intake to meet the needs of this macronutrient. 47,48 Although, in general, UPF have an unbalanced nutritional composition, a recent study showed that it is possible to prepare a menu composed mostly of UPF (>80% of total kcal) and still have good quality according to the Healthy Eating Index-2015 (HEI-2015), with an adequate distribution of macronutrients according to the dietary reference intakes. 49 In this context, among the markers of UPF consumption, our analysis found a significant negative relationship only between group 4 (sandwich biscuits, sweets or treats) and the percentage of protein in the diet.…”

Protein Intake and Bone Health in the Elderly

“…Protein typically makes up for 10 to 35 % of caloric intake in healthy subjects. The protein leverage hypothesis suggests that most species including humans target an average protein intake of 14 % [1].…”