Which supplements for skin health?
Quick summary
Food supplements can support hydration, dermal density and certain signs of skin ageing, provided they deliver documented nutrients at doses studied over 8 to 16 weeks.
Key facts
Key points
- A 2026 meta-analysis covering 19 randomised trials and 1,341 participants concludes that oral peptides have a modest effect on wrinkles (mean difference 0.27, p = 0.04) and a more marked effect on skin hydration and radiance (Nukaly et al., Frontiers in Medicine).
- Supplementation with hydrolysed collagen at 5 g per day for 12 to 16 weeks has shown a significant improvement in dermal density and skin texture in several double-blind randomised trials (Žmitek 2024, Vleminckx 2024).
- A 2023 JAMA Dermatology systematic review, which analysed 42 clinical studies in 3,346 patients, suggests a possible role for omega-3, vitamins B5 and D and probiotics in the treatment of acne, with a moderate level of evidence.
- The FSVO points out that food supplements are not medicines and cannot be presented as curing or preventing a disease; the maximum amounts of vitamins and minerals are set by the Swiss Food Supplements Ordinance (repealed in 2017) and current Swiss food legislation (SR 817.022.14).
Almost 30% of adults in Switzerland have taken at least one food supplement in the past seven days, according to the 2023 Swiss Nutrition Bulletin. On beauty websites, the food supplement keeps coming back as a promise of firmer, smoother and better hydrated skin. Recent clinical trials provide precise figures on collagen, vitamin C, zinc or oral hyaluronic acid, but also clear limitations. This article is part of the dossier on the proven benefits of food supplements and takes stock of what the skin can realistically expect, at what dose and within what timeframe.
How food supplements act on the skin
What is the mechanism of action on the skin?
A skin food supplement delivers to the skin from the inside specific nutrients — amino acids, vitamins, trace elements, antioxidants — that may support collagen production, the hydrolipid barrier and defence against free radicals. The journey from oral intake to the skin depends on intestinal absorption, blood transport and then uptake by skin cells, which play a key role in skin hydration and balance. A 2026 meta-analysis covering 19 randomised trials and 1,341 participants[1] confirmed that oral peptides were better tolerated than topical forms, with a significant effect on skin hydration and complexion radiance.
Which skin functions can they act on?
The nutrients studied target four main skin functions depending on the type of skin (normal, dry or combination skin): collagen and elastin production, hydration through retention of water in the dermis, the inflammatory response and the protective antioxidant action against oxidative stress. Clinical trials measure these functions through objective markers[1] — dermal density, water content of the stratum corneum, wrinkle depth, sebum production. Not all skin food supplements cover all of these functions: a hydrolysed collagen alone neither treats acne nor is enough to regulate sebum, and zinc for the skin alone does not slow the intrinsic ageing of the face.
The most studied nutrients for the skin
Does hydrolysed collagen improve the skin?
Recent clinical trials observe an improvement in skin firmness and texture after 8 to 16 weeks of supplementation with hydrolysed collagen at 5 g per day, presented as a capsule or as a sachet to dilute in a large glass of water. A Slovenian double-blind randomised study on 87 women[2] with mature skin, aged 40 to 65, documented a significant increase in dermal density with 5 g of collagen and 80 mg of vitamin C, without a significant effect on skin elasticity or hydration at 16 weeks. A second double-blind trial on 85 Asian women[3] found a significant improvement in dermal density and skin hydration after 84 days at 5 g per day of collagen peptides. Results on wrinkles and skin laxity remain modest — a mean difference of 0.27 in the 2026 meta-analysis[1].
What role for vitamin C, zinc and vitamin A?
Vitamin C is an indispensable cofactor of collagen production and a documented skin antioxidant, essential for fighting free radicals and supporting the immune system; the recommended daily intake in Switzerland is 100 mg for adults according to the Swiss Society of Nutrition. Zinc for the skin is studied for sebum regulation and the reduction of moderate to severe acne through its anti-inflammatory action on the skin, with variable results depending on dose and form used — the 2023 JAMA Dermatology review (42 trials, 3,346 patients)[5] nonetheless reports gastrointestinal adverse effects that limit compliance. Vitamin A and its derivatives are at the heart of official dermatological treatments for severe acne, such as oral isotretinoin prescribed by a dermatologist; in over-the-counter supplements, doses are strictly capped by the FSVO[8] to limit the hepatic and teratogenic risks.
Are oral hyaluronic acid and omega-3 useful?
A 2025 meta-analysis of 7 randomised trials[7] concludes that oral hyaluronic acid supplementation leads to a significant improvement in skin hydration, elasticity and wrinkle depth, with non-significant effects on skin firmness and transepidermal water loss. Essential omega-3 fatty acids, as well as omega-6 from plant oils of natural origin such as evening primrose oil or borage oil, are studied for skin inflammation and certain forms of acne; they are mentioned as beneficial by the 2023 JAMA Dermatology review[5] with a moderate level of evidence. None of these skin nutrients replaces a balanced diet: the combined benefit of a varied diet rich in fruit, vegetables and oily fish, together with targeted supplementation for a proven deficiency, remains more convincing than the isolated intake of a single natural product.
Expected effects by profile and timing
How long before you see results?
Most clinical trials observe the first visible effects on skin beauty and a healthy complexion between 4 and 8 weeks of continuous supplementation, with a plateau between 12 and 16 weeks. A Korean study[4] documented a significant improvement in wrinkle depth, skin elasticity and hydration after 8 weeks at 1,650 mg per day of low-molecular-weight collagen peptides in capsules, with the effects maintained during the two weeks following discontinuation. At 5 g per day[3], supplementation with marine or bovine collagen helps to maintain dermal density between 8 and 12 weeks. An anti-ageing course of less than 8 weeks has little chance of producing an observable change and a lasting radiant complexion.
What can be expected for wrinkles, elasticity and hydration?
The best-documented effect is the improvement in skin hydration and dermal density; the effects on wrinkle depth and skin elasticity remain variable depending on the studies and molecules. The 2026 meta-analysis (19 trials, 1,341 participants)[1] notes a modest effect of oral peptides on wrinkles (mean difference 0.27) and a more marked effect on hydration and complexion radiance. In 60 women with mature skin aged 35 to 65[6], 60 mg per day of a hyaluronic acid matrix for 12 weeks improved hydration, radiance and roughness, with brighter skin and a reduction in erythema. No supplement is enough to protect the skin daily without sun protection and the use of a sunscreen, which remain the leading protective factor against extrinsic skin ageing and the prevention of premature ageing.
Limitations and precautions in Switzerland
What are the risks of overdose?
The FSVO[8] warns about the risk of vitamin and mineral overdose, in particular with highly dosed products or when several supplements in tablet or capsule form are taken at the same time. Swiss food legislation (SR 817.022.14)[8] sets maximum amounts per recommended daily intake, calculated from the tolerable upper intake levels and based on the model of the German Federal Institute for Risk Assessment (BfR, 2018). Tox Info Suisse recorded around 1,200 enquiries linked to food supplements between 2014 and 2019, two thirds of which concerned accidental ingestions in young children. Oral vitamin A presents a hepatic and teratogenic risk at high prolonged doses: do not combine products without consulting a healthcare professional.
When is a supplement not the right answer?
The FSVO[9] reminds consumers that a varied, balanced diet covers the nutritional needs of the human body for the majority of healthy adults. A food supplement does not correct repeated sun exposure, tobacco use or major dietary imbalance, which are the primary levers for maintaining healthy skin and genuine skin health. For persistent skin conditions — inflammatory acne, rosacea, eczema, very marked ageing — consulting a healthcare professional remains the priority before any self-supplementation: choosing a useful food supplement requires qualified advice. Under Swiss food legislation[8], a food supplement cannot be presented as curing, relieving or preventing a disease.
Frequently asked questions
What is the best food supplement for the skin?
No supplement is universally superior to the others. The best-documented clinical trials concern hydrolysed collagen peptides at 5 g per day, with an improvement in dermal density and hydration after 8 to 12 weeks (Vleminckx et al., 2024). Vitamin C, zinc and oral hyaluronic acid also have clinical evidence depending on the target: hydration, firmness, acne or radiance. The choice therefore depends on the goal. Asking a doctor or pharmacist for advice remains the best approach to target useful supplementation and avoid pointless stacking.
From what age should you take a supplement for the skin?
No official age threshold exists in Switzerland. Clinical trials on collagen have mainly been conducted between 35 and 65 years of age, the period when the natural production of collagen gradually decreases. The FSVO points out that a varied diet covers the majority of needs; for young adults, the priority remains sun protection and a healthy lifestyle. Before age 18, in pregnancy or during breastfeeding, supplementation requires medical advice because of the teratogenic or hepatic risk of certain vitamins such as vitamin A.
How long should you take collagen to see an effect?
Between 8 and 16 weeks of continuous supplementation. A significant improvement in dermal density is observed at 84 days in the Vleminckx et al. (2024) study on 85 women taking 5 g per day of collagen peptides. The effects on wrinkles remain modest (mean difference 0.27 in the Nukaly et al., 2026 meta-analysis). A course of less than 8 weeks has little chance of producing an observable change, and the effects observed generally persist for a few weeks after the course ends (Lee et al., 2025).
Can you combine several food supplements for the skin?
It is possible, but with caution. Combining several products multiplies the risk of exceeding the maximum tolerable intakes set by the FSVO, particularly for vitamin A, zinc and selenium. The Žmitek et al. (2024) study on the combination of collagen + vitamin C + hyaluronic acid did not show superiority over collagen + vitamin C alone. Before any stacking, it is useful to check the combined doses with a pharmacist, particularly during ongoing medical treatment, to avoid interactions and silent overdoses.
Can diet alone be enough for the skin?
Yes, in the majority of cases, for healthy adults. The FSVO indicates that a varied, balanced diet covers needs in vitamins and minerals essential for the skin. Supplements become useful in the event of a proven deficiency — vitamin D in winter, for example — or specific needs linked to pregnancy or a vegan diet. For the skin, no supplement replaces daily sun protection or stopping smoking: these two levers have a far greater impact than oral supplementation.
Sources and references
9 sources- Nukaly H. Y. et al. (2026). Oral and topical peptides for skin aging: systematic review and meta-analysis of randomized controlled trials.
- Žmitek K. et al. (2024). The Effects of Dietary Supplementation with Collagen and Vitamin C and Their Combination with Hyaluronic Acid on Skin Density, Texture and Other Parameters.
- Vleminckx S. et al. (2024). Influence of collagen peptide supplementation on visible signs of skin and nail health and -aging in an East Asian population.
- Lee E. et al. (2025). Skin Anti-Aging and Moisturizing Effects of Low-Molecular-Weight Collagen Peptide Supplementation in Healthy Adults.
- Shields A. et al. (2023). Safety and Effectiveness of Oral Nutraceuticals for Treating Acne: A Systematic Review.
- Montero-Vilchez T. et al. (2025). Oral Supplementation with a New Hyaluronic Acid Matrix Ingredient Improves Skin Brightness, Hydration, Smoothness, and Roughness.
- Amin P. et al. (2025). Oral Hyaluronic Acid Supplement: Efficacy in Skin Hydration, Elasticity, and Wrinkle Depth Reduction.
- FSVO — Federal Food Safety and Veterinary Office. Food supplements: legal framework and requirements.
- FSVO. Food supplements — a use reserved for certain situations.