The Study
Thermic response to isoenergetic protein, carbohydrate or fat meals in lean and obese subjects.
This study looked at what happens to your body after you eat different foods — like protein, carbs, or fat — in 10 people (5 thin, 5 heavier). It found that eating protein made your body burn more energy afterward, and heavier people had higher blood sugar after eating carbs. But because the study didn’t randomly assign who ate what or hide what they were eating, we can’t say the food caused these changes — only that they were linked.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
When you eat protein, your body works harder to digest it than when you eat carbs or fat — and this happens whether you're lean or obese.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 537 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — eating protein boosts calorie burn more than other foods, even in obesity, and high blood sugar after carbs isn't due to poor glucose use by cells.
- 2Protein meals burned 2-3x more energy than carbs or fat.
- 3Obese people had higher insulin and blood sugar after carbs, but used dietary glucose just as well as lean people.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Related Content
Claims (6)
Eating protein causes the body to burn more calories during digestion than eating the same amount of carbohydrates or fats, because breaking down and processing protein requires more energy.
People with obesity tend to have higher insulin levels when fasting and their blood sugar spikes more after eating carbs, but their bodies still use the sugar from those carbs just like lean people do.
Eating protein makes your body burn more calories after eating than eating the same amount of carbs or fat, no matter if you're lean or obese.
Obese and lean people burn about the same number of extra calories after eating the same amount of food, no matter if it’s protein, carbs, or fat.
Even though obese people have higher blood sugar after eating carbs, their bodies still break down and use the sugar from those carbs just as well as lean people do.
Past studies that said obese people burn fewer calories after eating might have been misleading because they compared obese people with unusually active lean people or included diabetic patients who burn more calories at rest.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.