The short answer
- For skin hydration and elasticity: might help
- Pooled trials favour collagen over placebo on skin measurements, but most of the trials are small and poorly protected against bias.
- For wrinkles: might help
- Nine of ten trials that measured wrinkle depth found an improvement. The reviewers still called the evidence preliminary.
- For joints, hair and nails: not proven
- Far less has been studied here, and what exists is mostly small trials in people with arthritis rather than in women going through menopause.
What it is
A protein that holds skin, tendon and bone together. Supplements are usually hydrolysed collagen, which means the protein has been broken into short pieces. It comes from cow hide and bone, pig skin, or fish skin and scales.
What the studies say
- A 2021 review and meta analysis pooled 19 randomized, double blind trials in 1,125 people, 95 per cent of them women. It found better skin hydration, elasticity and wrinkles with hydrolysed collagen than with placebo.
- Those trials ran for about 90 days.
- A 2026 systematic review of 25 randomized trials found the same direction of travel. Hydration improved in 10 of 15 trials, elasticity in 10 of 13, and wrinkle depth or volume in 9 of 10.
- That same review rated the majority of the trials at high risk of bias, and called the evidence preliminary. It asked for larger, longer, better run trials.
- Trial sizes ranged from 13 people to 236. These are small studies by the standards of anything else on this page.
- Nothing in these trials was about menopause. They measured skin in adults.
How much people take in trials
The pooled trials ran for about 90 days. The doses varied too much between products for us to give one number.
This is what the research used. It is not a dose for you.
What a label is allowed to say
No claim is approved for collagen itself. Brands often add vitamin C so they can say vitamin C contributes to normal collagen formation. The UK advertising regulator has ruled against collagen adverts that promised better skin.
In the US the rules are looser. A label may say how a nutrient supports the body if the company holds evidence for it. The FDA does not check the claim first, which is why US labels carry the line saying the FDA has not evaluated it.
Safety
- Side effects in trials were uncommon and mild.
- Collagen is an animal product. If you are allergic to fish or shellfish, check the source on the label, because marine collagen is common.
- It is not suitable if you avoid animal products.
- Collagen is a protein, so if you have kidney disease and have been told to watch your protein, count it in.
Ask your doctor first if
- You have a fish, shellfish or egg allergy.
- You have kidney disease and have been given a protein limit.
- You are taking it instead of something your doctor has suggested for your skin.
This is general information, not medical advice. Check with your doctor or pharmacist, especially if you take medication.