Low Protein Diets and Energy Balance: Mechanisms of Action on Energy Intake and Expenditure.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing preclinical mechanistic and animal research without systematic review methodology or new human data.
PubMed 34055853 · doi:10.3389/fnut.2021.655833
What was done
This mini-review synthesized literature examining the effects of low-protein diets (with varied carbohydrate and lipid content) on energy intake, energy expenditure, body weight, and adiposity, focusing on the underlying neuroendocrine and metabolic mechanisms.
What was found
The abstract reports no numerical data or effect sizes. It qualitatively notes that moderate-to-severe protein restriction induces hyperphagic feeding responses while also elevating energy expenditure and thermogenesis through enhanced sympathetic flux to brown adipose tissue, fibroblast growth factor-21 (FGF21), and serotonergic signaling, often resulting in decreased body weight and adiposity in animal models.
Why it matters
Clarifying the neuroendocrine pathways connecting dietary protein dilution to thermogenesis and caloric compensation highlights potential therapeutic targets, such as FGF21 pathways, for managing human metabolic disease.
Limits
The review relies primarily on preclinical rodent experiments, limiting direct generalizability to human nutrition. It is a non-systematic narrative review, and the abstract provides no quantitative data, search parameters, or study selection criteria.
Cited by
- context A low-protein, high-sugar diet stimulates the generation of fibroblast growth factor (FGF), which converts into high metabolic energy.