The Study
Use of Novel High-Protein Functional Food Products as Part of a Calorie-Restricted Diet to Reduce Insulin Resistance and Increase Lean Body Mass in Adults: A Randomized Controlled Trial
This study tried two different diets on a small group of people who were at risk for diabetes and found that one diet made their insulin work better. But because only 21 people finished, we can't say for sure it would work the same for everyone else.
Analysis score
Maximum 45 for a randomized controlled trial.
Where the score came from
When people cut calories to lose weight, they often lose muscle too. This study tested if eating more protein from special foods could help keep or even build muscle while losing weight.
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 545 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes—this means you can lose weight without losing muscle if you eat enough high-quality protein spread across meals, which may also improve your metabolic health faster.
- 2People who ate 125g of special high-protein foods daily gained 1.5 kg of muscle and cut insulin resistance by 1.7 points.
- 3Those who ate 80g of normal foods lost 0.5 kg of muscle and cut insulin resistance by only 0.7 points—even though both groups ate the same number of calories and lost similar weight.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Nutrients
Year
2017
Authors
C. Johnston, B. Sears, Mary Perry, Jessica R. Knurick
Related Content
Claims (5)
When calorie intake is lowered, consuming a high-protein diet results in greater lean muscle mass compared to lower-protein diets.
Among adults at risk for insulin resistance, a 6-week low-calorie diet with 125 grams of protein per day from wheat gluten and whey increased lean body mass by 1.5 kg and lowered insulin resistance by 1.7 HOMA-IR units, while a diet with 80 grams of protein per day decreased lean body mass by 0.5 kg and lowered insulin resistance by 0.7 HOMA-IR units.
When people reduce calorie intake, a decrease in insulin resistance is linked to a preservation or increase in lean body mass, regardless of how much total weight is lost.
In adults with high triglyceride and low HDL levels, a 6-week calorie-restricted diet using special high-protein foods does not change levels of oxidative stress or inflammation markers, and any improvement in insulin resistance is not due to changes in these inflammation markers.
Among adults at risk for insulin resistance, a six-week low-calorie diet with high-protein functional foods reduces insulin resistance 140% more than a low-calorie diet with standard lower-protein foods, even when total calories and weight loss are the same.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.