Controversies Surrounding High-Protein Diet Intake: Satiating Effect and Kidney and Bone Health

Abstract

Long-term consumption of a high-protein diet could be linked with metabolic and clinical problems, such as loss of bone mass and renal dysfunction. However, although it is well accepted that a high-protein diet may be detrimental to individuals with existing kidney dysfunction, there is little evidence that high protein intake is dangerous for healthy individuals. High-protein meals and foods are thought to have a greater satiating effect than high-carbohydrate or high-fat meals. The effect of high-protein diets on the modulation of satiety involves multiple metabolic pathways. Protein intake induces complex signals, with peptide hormones being released from the gastrointestinal tract and blood amino acids and derived metabolites being released in the blood. Protein intake also stimulates metabolic hormones that communicate information about energy status to the brain. Long-term ingestion of high amounts of protein seems to decrease food intake, body weight, and body adiposity in many well-documented studies. The aim of this article is to provide an extensive overview of the efficacy of high protein consumption in weight loss and maintenance, as well as the potential consequences in human health of long-term intake.

Nutritional Approaches to Achieve Weight Loss in Nonalcoholic Fatty Liver Disease

“…Thus, these studies are promising, but participants were only given a high-protein diet for short duration of time. Thus, more studies would be needed to assess the long-term effects of a high-protein diet, because a high-protein diet can worsen chronic kidney disease (92).…”

Combined effects of resistance training and carbohydrate-restrictive or conventional diets on weight loss, blood variables and endothelium function

“…These results were probably due to the maintenance of total protein intake. Although it is well accepted that a high-protein diet may be detrimental to individuals with existing kidney dysfunction, there is little evidence that high protein intake is dangerous for healthy individuals 31 . Based on the current evidence, CRD interventions do not seem to impair organic functions in obese subjects, even over a two-year period 32 .…”

Nutrients, Nutraceuticals and Xenobiotics Affecting Renal Health

“…Third, proteins are particularly required in some special life phases and situations: pregnancy and infancy, elderly, intensive physical activity. They also become critical in the context of low-calorie to achieve weight loss as they prevent lean mass waste [3].…”

“…Obesity and its comorbidities such as hypertension, insulin resistance and diabetes, currently represent the main risk factors for CKD. In terms of prevention of renal diseases, diets with a protein intake that exceeds the RDA represent a valuable tool for weight control and should therefore be used in order to achieve or maintain the weight loss goal, or to prevent malnutrition in the elderly, thanks to their effects on basal metabolism and thermogenesis increase, satiety induction, and body recomposition boosting [3]. In our opinion, it is necessary to enhance the routine renal function testing in the general population, for both renal disease prevention and also to avoid wrong prescriptions of high-protein diets which can turn out to be harmful in case of kidney dysfunctions.…”

“…In this respect, protein [3] and fiber [4][5][6] intakes are fundamental tools in the dietary control of these risk factors. Some hints do exist pointing to the importance of gut microbiota balance in the prevention of renal function decline [7] with fibres playing a primary role in the modulation of microbial metabolism.…”