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The Study

Short-term effects of high-protein, lower-carbohydrate ultra-processed foods on human energy balance

In simple terms

This study is like a fair test where 21 people ate two different kinds of ultra-processed meals for a few days, and scientists measured exactly how much they ate and how many calories they burned. It shows that one kind of meal made them eat less and burn more — so we can say this diet caused those changes in the short term.

78%

Analysis score

78/ 90

Maximum 90 for a randomized controlled trial.

Where the score came from

Reporting40
Methodology70
Publication100
Statistical100
Study type (basis of the score)
Randomized Controlled Trial
Level 1b - Individual RCT
What’s the bottom line?

Even if the food is ultra-processed (like packaged snacks), eating more protein and less carbs makes your body burn more calories and feel fuller faster.

Where does this study sit?

Reviews of RCTs (Meta-analyses)

Max 100

Randomized Trials

Max 90

Reviews of Cohort Studies

Max 85

Cohort Studies

Max 72

Reviews of Case-Control Studies

Max 63

Case-Control Studies

Max 58

Cross-Sectional & Case Series

Max 50

Expert Opinion

Max 5
StrongerWeaker
Randomized Trials
Level 1b
78

78 / 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.

Can establish causation

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Key takeaways

Summary

Based on the study abstract and findings.

  1. 1Yes — cutting 196 kcal/day is like skipping a small snack daily, which could lead to weight loss over time.
  2. 2People ate 196 fewer calories per day, burned 128 more calories per day, and had a 14% better energy balance (less fat gain) on a high-protein ultra-processed diet.

Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data

Publication

Journal

Nature Metabolism

Year

2025

Authors

F. Hägele, C. Herpich, Jana Koop, Jonas Grübbel, R. Dörner, S. Fedde, Oliver Götze, Y. Boirie, M. J. Müller, Kristina Norman, Anja Bosy-Westphal

Open Access
14 citations
Analysis v6

Related Content

Claims (10)

Assertion

When people consume 30% of their daily calories from protein without restricting food intake, they eat fewer calories overall and lose body fat.

Causal
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Assertion

When healthy young adults eat an ultra-processed diet higher in protein and lower in carbohydrates for 54 hours, they consume 196 fewer calories per day than when eating an ultra-processed diet lower in protein and higher in carbohydrates, even when both diets taste equally good and have the same fat and fiber content.

Causal
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Assertion

In healthy young adults, eating a diet high in protein and low in carbohydrates made from ultra-processed foods raises glucagon and peptide YY levels and lowers ghrelin levels after meals compared to a diet with normal amounts of protein and carbohydrates made from ultra-processed foods.

Mechanistic
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Assertion

In healthy young adults, eating a diet high in protein and low in carbohydrates for 54 hours reduces the excess energy stored in the body from 32% to 18% compared to a diet with normal protein and carbohydrate levels.

Causal
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Assertion

When people increase the proportion of protein in their diet from 15% to 30% of total calories, they consume about 400 fewer calories per day without trying to restrict food intake.

Causal
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Assertion

In healthy young adults, eating a diet of mostly ultra-processed foods with higher protein and lower carbohydrates for 54 hours reduces daily calorie intake by 196 kcal and increases total daily energy expenditure by 128 kcal compared to a diet with lower protein and higher carbohydrates, leading to a smaller net energy surplus despite both diets having the same taste and calorie density.

Causal
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Fit Body Science verdict — we translate health studies into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.