For overweight or obese adults, losing weight with a high-protein diet first and then switching to a low-glycemic-index diet results in more fat loss and less muscle loss than starting with the...
Mechanism
Synthesis from 1 study
Eating more protein first keeps your muscles from shrinking and makes you feel full longer, so you burn more calories and eat less. When you switch to low-sugar foods later, your body is already burning fat efficiently because your muscles are still there and your appetite is under control.
Most probable mechanism
Starting with a high-protein diet tells the body to hold onto muscle by boosting muscle building and slowing muscle breakdown. This keeps metabolism high, so more fat gets burned. It also makes you feel fuller longer, so you eat less without trying. When you switch to a low-glycemic diet later, your body is already burning fat efficiently because muscle is still intact and energy use stays high.
Increased dietary protein elevates plasma branched-chain amino acids, particularly leucine
Leucine activates the mTORC1 signaling pathway in skeletal muscle
mTORC1 activation increases muscle protein synthesis and suppresses ubiquitin-proteasome-mediated protein breakdown
Preserved muscle mass maintains higher resting and 24-hour energy expenditure
Protein ingestion stimulates release of glucagon-like peptide-1 and peptide YY from intestinal L-cells
Glucagon-like peptide-1 and peptide YY suppress appetite by acting on hypothalamic nuclei
Reduced ghrelin secretion decreases hunger signaling
Sustained satiety reduces spontaneous energy intake, deepening the energy deficit beyond prescribed restriction
Higher energy expenditure and deeper energy deficit together increase fat mass loss
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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