When people who lost weight eat more protein and fewer carbs, their bodies burn more calories at rest and end up in a calorie deficit, which might help them keep the weight off.
Scientific Claim
In adults with prediabetes who have previously lost weight, a high-protein diet (25% of energy from protein) increases resting energy expenditure by approximately 0.5 MJ/day compared to a moderate-protein diet (15% of energy from protein), resulting in a negative energy balance of -0.5 MJ/day versus a near-neutral balance of +0.2 MJ/day, which suggests a metabolic advantage that may help resist weight regain.
Original Statement
“EB (MP = 0.2 ± 0.9 MJ/d; HP = −0.5 ± 0.9 MJ/d) and RQ (MP = 0.84 ± 0.02; HP = 0.82 ± 0.02) were reduced and REE (MP: 7.3 ± 0.2 MJ/d compared with HP: 7.8 ± 0.2 MJ/d) was increased in the HP group compared with the MP group (P < 0.05).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
This is a well-controlled RCT with randomization and direct measurement of energy expenditure and balance. The study design supports causal inference, and the verbs 'increases' and 'results in' are appropriate given the intervention and measured outcomes.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether high-protein diets consistently increase resting energy expenditure and induce negative energy balance across diverse post-obese populations with prediabetes or type 2 diabetes.
Whether high-protein diets consistently increase resting energy expenditure and induce negative energy balance across diverse post-obese populations with prediabetes or type 2 diabetes.
What This Would Prove
Whether high-protein diets consistently increase resting energy expenditure and induce negative energy balance across diverse post-obese populations with prediabetes or type 2 diabetes.
Ideal Study Design
A meta-analysis of 15+ randomized controlled trials (each n≥50) comparing high-protein (≥25% energy) vs. moderate-protein (≤15% energy) diets in adults with prediabetes or obesity-related insulin resistance, all using respiration chamber measurements of REE and energy balance at ≥12 months post-weight loss, with body weight change as secondary outcome.
Limitation: Cannot establish causation in individual participants or isolate protein effects from other dietary or behavioral confounders.
Randomized Controlled TrialLevel 1bWhether a high-protein diet prevents weight regain over 2+ years in post-obese adults with prediabetes by sustaining negative energy balance and reduced adaptive thermogenesis.
Whether a high-protein diet prevents weight regain over 2+ years in post-obese adults with prediabetes by sustaining negative energy balance and reduced adaptive thermogenesis.
What This Would Prove
Whether a high-protein diet prevents weight regain over 2+ years in post-obese adults with prediabetes by sustaining negative energy balance and reduced adaptive thermogenesis.
Ideal Study Design
A double-blind, parallel-group RCT of 200+ adults (age 50–75, BMI 27–35, prediabetic) randomized to 25% protein vs. 15% protein diets for 24 months after a 10% weight loss, with primary outcome being weight regain (kg) and secondary outcomes including 48-h respiration chamber-measured REE, AT, and energy balance at 6, 12, and 24 months.
Limitation: Cannot prove mechanism (e.g., UCP upregulation) without biomarkers or tissue sampling.
Prospective Cohort StudyLevel 2bWhether individuals consuming higher protein diets after weight loss are less likely to regain weight over 5+ years in real-world settings.
Whether individuals consuming higher protein diets after weight loss are less likely to regain weight over 5+ years in real-world settings.
What This Would Prove
Whether individuals consuming higher protein diets after weight loss are less likely to regain weight over 5+ years in real-world settings.
Ideal Study Design
A 5-year prospective cohort of 1000+ adults who lost ≥10% body weight, tracking habitual protein intake (via food diaries) and weight trajectory, adjusting for physical activity, sleep, and baseline metabolic rate, with AT estimated via predictive equations.
Limitation: Cannot prove causation due to potential confounding by lifestyle, motivation, or socioeconomic factors.
Controlled Animal StudyLevel 4Whether high-protein intake directly upregulates uncoupling proteins (UCP1/2/3) in adipose or muscle tissue to increase energy expenditure after weight loss.
Whether high-protein intake directly upregulates uncoupling proteins (UCP1/2/3) in adipose or muscle tissue to increase energy expenditure after weight loss.
What This Would Prove
Whether high-protein intake directly upregulates uncoupling proteins (UCP1/2/3) in adipose or muscle tissue to increase energy expenditure after weight loss.
Ideal Study Design
A controlled study in 60 obese-prone rats, inducing 15% weight loss via caloric restriction, then randomizing to high-protein (30% energy) or moderate-protein (15% energy) diets for 12 weeks, measuring UCP mRNA/protein expression in brown fat, skeletal muscle, and liver via qPCR and Western blot, alongside 24-h energy expenditure.
Limitation: Cannot be directly translated to human physiology due to species differences in metabolism and adipose biology.
Evidence from Studies
Supporting (1)
This study found that people who lost weight and ate more protein burned more calories at rest and stayed in a calorie deficit, while those who ate less protein didn’t — exactly what the claim says.