When overweight or obese adults follow a short-term low-calorie diet with 30% protein, their LDL cholesterol decreases more and they lose less muscle mass than when they follow a low-glycemic-index...
Mechanism
Synthesis from 1 study
Eating more protein while cutting calories tells the liver to remove more bad cholesterol from the blood and keeps muscles from breaking down. The same protein intake also makes you feel fuller longer, so you naturally eat less than planned.
Most probable mechanism
Eating more protein while cutting calories tells the liver to remove more bad cholesterol from the blood and keeps muscles from breaking down, even when the body is in energy deficit.
Increased dietary protein elevates plasma branched-chain amino acids, particularly leucine, in skeletal muscle
Leucine activates the mTORC1 signaling pathway in skeletal muscle, stimulating ribosomal biogenesis and translation initiation to increase muscle protein synthesis
Higher protein intake suppresses ubiquitin-proteasome-mediated proteolysis in skeletal muscle, reducing muscle protein breakdown during energy deficit
Preserved muscle mass maintains higher resting energy expenditure, sustaining a greater net energy deficit that promotes fat loss
Dietary protein modulates hepatic SREBP-2 activity to upregulate LDL receptor expression on hepatocytes
Increased LDL receptor density enhances hepatic uptake and catabolism of circulating LDL particles, reducing plasma LDL-cholesterol concentration
Less supported by current evidence, but not ruled out
High protein intake triggers gut hormones that signal fullness to the brain, leading to reduced food intake beyond what is prescribed by the diet.
Ingestion of protein stimulates L-cells in the distal small intestine to secrete glucagon-like peptide-1 and peptide YY
Glucagon-like peptide-1 and peptide YY bind to receptors in the hypothalamus to suppress appetite and enhance satiety signals
Reduced ghrelin secretion from the stomach decreases hunger signaling
Sustained satiety reduces spontaneous energy intake, deepening the negative energy balance beyond the prescribed caloric restriction
Evidence from Studies
Supporting (1)
Community contributions welcome
High-Protein or Low Glycemic Index Diet—Which Energy-Restricted Diet Is Better to Start a Weight Loss Program?
Contradicting (0)
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Gold Standard Evidence Needed
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