Collagen Peptides & Exercise: Do They Help You Eat Less?

study PMID: 40685650

Quick Summary: A recent study found that taking collagen peptides might help active women eat fewer calories after exercise. It didn't change how hungry they felt, but they consumed about 19% fewer calories compared to a control group.

Does Collagen Affect Appetite?

This study looked at whether collagen peptides could impact how much food people ate after exercising. The results showed that collagen didn't significantly change how hungry or full the women felt. However, it did affect how much they ate.

What The Research Found

Less Food After Exercise: Women who took collagen peptides ate about 19% fewer calories after exercising compared to those who didn't.

No Change in Hunger: Collagen didn't seem to make them feel more or less hungry.

Hormones Unchanged: The study didn't find any changes in hormones related to appetite, like ghrelin and GLP-1.

Study Details

Who was studied: 15 healthy, active women, average age 23.

How long: The study lasted for 7 days.

What they took: Participants took 15 grams of collagen peptides daily or a taste-matched placebo (a substance with no active effect). On the 7th day, they exercised.

What This Means For You

Potential for Weight Management: If you're an active woman, taking collagen peptides might help you consume fewer calories after exercise. This could potentially support weight management, but it's not a magic bullet.

Don't Expect Appetite Changes: Don't expect collagen to make you feel less hungry. The study didn't find any impact on appetite.

Combine with Exercise: The study suggests the effect is linked to exercise, so it's not a replacement for a healthy lifestyle.

Study Limitations

Small Study: Only 15 women participated, so the results might not apply to everyone.

Short Duration: The study only lasted a week, so we don't know if the effects would last longer.

Specific Group: The study only included young, healthy women. It's unclear if the results would be the same for men, older adults, or people with health conditions.

More Research Needed: The study didn't explain why collagen might reduce calorie intake. More research is needed to understand how it works.

Self-Reported Appetite: The study relied on self-reported feelings of hunger, which can be subjective.

Key Findings

The study found that collagen peptide (CP) supplementation did not significantly alter appetite sensations but reduced post-exercise energy intake by 19% compared to a control (CON) in healthy, active females. Participants consumed fewer calories after CP supplementation (mean: 452 ± 134 kcal) versus CON (558 ± 152 kcal), with a statistically significant difference (p = 0.03). No notable changes in macronutrient intake or appetite-related hormones (ghrelin, GLP-1) were observed.

Study Design

This was a randomised, double-blind, crossover controlled trial involving 15 healthy females (age: 23 ± 3 years). Each participant underwent two 7-day interventions: 15 g/day of CP or a taste-matched, non-energy control (CON). On day 7, all completed 45 minutes of moderate-intensity cycling (∼55% W). Appetite was measured pre- and post-exercise via visual analog scales (VAS) and blood samples, followed by an ad libitum meal to assess energy intake.

Dosage & Administration

Participants received 15 g/day of collagen peptides (type unspecified) dissolved in water or a placebo (CON) with identical taste and appearance. Supplements were administered daily for 7 days, with the final dose consumed 30 minutes before exercise on day 7.

Results & Efficacy

Appetite: No significant differences in area under the curve (AUC) for hunger, satiety, or desire to eat between CP and CON (p = 0.18).
Energy Intake: CP reduced post-exercise energy intake by 19% compared to CON (452 ± 134 kcal vs. 558 ± 152 kcal; p = 0.03).
Hormones: Ghrelin and GLP-1 levels showed no meaningful changes post-exercise (p > 0.05).
Macronutrients: Protein, carbohydrate, and fat intake trends were lower with CP but not statistically significant.

Limitations

Small sample size (n = 15), limiting generalisability.
Short intervention duration (7 days), preventing assessment of long-term effects.
Homogeneous population (young, healthy females), reducing applicability to males, older adults, or clinical groups.
Appetite measured via self-reported VAS, which may lack sensitivity.
No adjustment for multiple comparisons, raising potential for Type I errors.
Mechanism of reduced energy intake remains unclear, as hormone levels and appetite ratings were unaffected.

Clinical Relevance

For active females, 15 g/day of CP may modestly reduce post-exercise calorie consumption without altering perceived hunger or satiety. This suggests potential utility in energy balance management when combined with moderate exercise. However, the lack of appetite modulation and short study duration warrant caution in interpreting practical benefits. Further research is needed to confirm these effects in diverse populations and explore metabolic or behavioral mechanisms. Users should consider individual variability and consult healthcare professionals before relying on CP for appetite control.

Source: PubMed | Date: 2025-07-21