9-Month Trial: Collagen Peptide Supplements Improve Pain, Function, and Mental Health in Active Middle-Aged Adults | Research

The takeaway

A 9-month randomized controlled trial found that 10-20 grams per day of collagen peptides improved daily function, pain, and mental and physical health scores in active middle-aged adults.

ηp²=0.309 for mental health
Large effect size for mental health improvement with 10 g/day collagen peptides over 3-9 months, representing a meaningful quality-of-life benefit

What the researchers found

At 10 g/day of collagen peptides over 6 months, significant improvements were seen in activities of daily living (p=0.031, effect size ηp²=0.096) and pain (p=0.037, ηp²=0.164), though pain improvements were limited to high-frequency exercisers (>180 min/week).

Mental component scores (VR-12 MCS) improved with 10 g/day over 3-9 months (p=0.017, ηp²=0.309). Physical component scores improved with 20 g/day over 3-9 months, but only in females (p=0.013, ηp²=0.582). The large effect sizes for mental health and female physical health outcomes are notable.

Why it matters

Chronic pain affects 19% of US adults and limits physical activity and quality of life. This is one of the longest collagen peptide supplementation studies in healthy active adults, demonstrating that a readily available, affordable supplement can meaningfully improve pain, daily function, and mental health — areas where existing interventions are often inadequate or carry side effects.

How the study worked

Double-blind randomized controlled trial with three groups: placebo, 10 g/day collagen peptides, and 20 g/day collagen peptides. Participants were middle-aged active adults assessed at 3, 6, and 9 months. Outcomes were measured using the KOOS (Knee Injury & Osteoarthritis Outcomes Score) for pain and function, and the VR-12 (Veterans Rand 12) for mental and physical health.

What this study cannot tell us

Sample size for each group was not specified in the abstract, which may limit statistical power. Pain improvements required high exercise frequency (>180 min/week), limiting generalizability to less active populations. Physical health improvements at 20 g/day were only significant in females. The study did not include biomarkers of collagen metabolism or joint imaging to confirm mechanisms.

How to read the evidence

This is a double-blind randomized controlled trial — a high level of evidence. The 9-month duration is notably longer than most collagen supplement studies. However, the abstract does not report the sample size, and some benefits were only significant in subgroups.

When this study was published

Published in 2023, this study represents recent and relevant evidence on collagen peptide supplementation in the active adult population.

The bigger picture

Collagen peptides are one of the most popular nutritional supplements, but long-term evidence in healthy active populations has been scarce. This study provides some of the strongest evidence yet for sustained benefits beyond joint health alone — extending to mental wellbeing and daily function. The dose-specific and sex-specific findings add important nuance for personalized supplementation recommendations.

Questions still open

Why did pain improvements only appear in high-frequency exercisers — does exercise enhance collagen peptide absorption or utilization?
Why did 10 g/day improve mental health while 20 g/day improved physical health in females — are there different dose-response relationships for different outcomes?
Would collagen peptide supplementation show similar benefits in sedentary or older populations with more advanced joint issues?

Common questions

How much collagen peptide should I take and how long until it works?

This study found benefits at both 10 g/day and 20 g/day, with different outcomes at each dose. At 10 g/day, daily function and pain improved by 6 months, and mental health improved by 3 months. At 20 g/day, physical health scores improved by 3 months in women. The key takeaway is that collagen peptide supplementation requires at least 3-6 months of consistent daily use to see meaningful results.

Does exercise affect how well collagen peptides work?

Yes — in this study, the pain-reducing benefits of collagen peptides at 10 g/day were only significant in people who exercised more than 180 minutes per week (about 3 hours). This suggests that physical activity may enhance the joint-protective effects of collagen supplementation, possibly by stimulating collagen turnover in joint tissues during exercise.

Read the original research

Collagen peptides supplementation improves function, pain, and physical and mental outcomes in active adults.

Journal of the International Society of Sports Nutrition, 20(1), 2243252

View on PubMed ↗Publisher’s paper ↗

Citation

Kviatkovsky, Shiloah A; Hickner, Robert C; Cabre, Hannah E; Small, Stephanie D; Ormsbee, Michael J. (2023). Collagen peptides supplementation improves function, pain, and physical and mental outcomes in active adults.. Journal of the International Society of Sports Nutrition, 20(1), 2243252. https://doi.org/10.1080/15502783.2023.2243252