Collagen is the springy protein that keeps skin firm. It appears in two ways: in creams and pads, where it stays on the surface, and in drinks or tablets as hydrolyzed collagen. Reviews of oral trials found better hydration and elasticity after about three months.
- Helps with
- loss of firmness, dryness, fine lines
- Evidence
- Moderate. Meta-analyses of randomized trials support oral hydrolyzed collagen for hydration and elasticity; topical collagen is too large to enter skin.
- Typical strength
- Oral trials ran about 90 days; doses vary by product
- Works well with
- vitamin C, daily sunscreen
What does collagen do for skin?
Collagen is the protein that gives skin its spring, the reason a pinch of young skin snaps back. When people talk about losing firmness, softer cheeks or fine lines settling in, collagen is usually part of the story. It shows up on labels in two very different forms.
Does collagen in creams get into skin?
No, not as collagen. A widely cited dermatology paper argues that “the molecular weight (MW) of a compound must be under 500 Dalton to allow skin absorption”, and adds that “Larger molecules cannot pass the corneal layer.” Collagen molecules are many times bigger than that limit. In a cream, pad or mask, collagen stays on the surface; it does not replace the collagen inside skin.
If the goal is more collagen inside skin, ingredients that signal skin to make its own are the ones studied for that, such as vitamin C, retinol and some peptides. A 2017 review describes vitamin C as increasing collagen synthesis and slowing its breakdown.
Do collagen drinks and supplements work?
The evidence here is better than for creams. Oral collagen is sold hydrolyzed, meaning broken into small pieces. A 2023 review pooled 26 randomized trials with 1,721 people and found hydrolyzed collagen improved skin hydration and elasticity compared with placebo. A 2021 review of 19 trials with 1,125 people aged 20 to 70, mostly women, also found better hydration, elasticity and wrinkles, and concluded that taking it for 90 days reduced signs of skin ageing.
How long until you notice a difference?
For supplements, the reviewed trials point to about 90 days. For creams and pads, collagen works only at the surface, so judge them as you would any moisturizer.
How do you use collagen?
As a supplement, follow the dose on the product and give it about three months. In skincare, treat collagen creams, toner pads and masks as moisturizers, and keep daily sunscreen in the routine, since sunlight drives much of the skin ageing these products are bought for.
Who should be careful with collagen?
Check the collagen source on a supplement label if you avoid certain animal products. Anyone who is pregnant, nursing or managing a health condition should check supplements with a doctor first.
- Bos JD, Meinardi MM. The 500 Dalton rule for the skin penetration of chemical compounds and drugs. Exp Dermatol. 2000;9(3):165-9.
- Pu SY, et al. Effects of oral collagen for skin anti-aging: a systematic review and meta-analysis. Nutrients. 2023;15(9):2080.
- de Miranda RB, Weimer P, Rossi RC. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. Int J Dermatol. 2021;60(12):1449-1461.
- Al-Niaimi F, Chiang NYZ. Topical vitamin C and the skin: mechanisms of action and clinical applications. J Clin Aesthet Dermatol. 2017;10(7):14-17.
- Pinnell SR, et al. Topical L-ascorbic acid: percutaneous absorption studies. Dermatol Surg. 2001;27(2):137-42.
Editorial content, not medical advice.