Silicon supplements: do you need them and how to choose
Silicon supplements are often bought in the hope of stronger hair and nails. Silicon is indeed found in the skin, bones and tendons. But will a supplement change anything?
In this article we explain in simple terms what the research shows, how much silicon you get from food, and how to choose a supplement if you still decide to take one.
In brief. It has not been possible to prove that silicon helps hair, nails, skin or bones, which is why the EU does not allow such claims on products.2 With an ordinary diet you get about 20–50 mg of silicon per day, and silicon deficiency has not been described in humans.1 If you choose a supplement, look at the form of silicon and the amount per serving, not at the wording on the packaging.
What is silicon?
Silicon (Si) is a trace element. It is found in grains, vegetables, drinking water and beer. Scientists are studying its relationship with collagen, a protein that supports the skin, bones and tendons.
However, silicon is not considered an essential nutrient. Its specific function in the human body has not been established, and no symptoms of deficiency have been described.1,6
Does silicon help hair and nails?
The short answer: the evidence is insufficient. Applications to authorise claims that silicon helps hair, nails, skin, bones or joints were assessed and rejected.2 An honest product should therefore not make such promises.
Example. In the most frequently cited study, 50 women took 10 mg of silicon per day or a placebo for 20 weeks.9 Some skin measurements improved, while the brittleness of hair and nails was assessed by the women themselves. The study is small, so firm conclusions cannot be drawn from it.
Results for bones are also modest. In a year-long study of 136 women, bone density did not change significantly with silicon.10
Which foods contain silicon?
Grain products contain the most silicon, especially oats and less refined grains.8 However, what matters is not only the amount, but also how much the body absorbs.
| Food | What the research shows | What it means for you |
|---|---|---|
| Oats, wholegrain bread, flakes | Among the richest sources of silicon.8 | Porridge for breakfast is a simple way to get silicon. |
| Green beans | About 44% of the silicon is absorbed.7 | A good vegetable choice. |
| Bananas | They contain a lot of silicon, but only about 4% is absorbed.7 | Do not count on them as a source of silicon. |
| Drinking water | The silicon in water is in an easily absorbed form.4 | The water you drink every day contributes as well. |
Which form of silicon should you choose?
Forms differ greatly in how much silicon the body actually absorbs. A bigger number on the packaging does not mean you will get more.
| Form | What the research shows | What it means for you |
|---|---|---|
| Monomethylsilanetriol (MMST, “organic silicon”) | About 64% is absorbed; safe up to 10 mg per day.5,7 | Low doses, good absorption. Usually a liquid. |
| Choline-stabilised orthosilicic acid (ch-OSA) | About 17% is absorbed; safe up to 10 mg per day.4,7 | Low doses. Contains choline. |
| Silicon dioxide, colloidal silicon | About 1% is absorbed; safe up to 700 mg per day.3,7 | A big number on the label, but only a small fraction is absorbed. |
| Horsetail or bamboo extract | The amount of silicon depends on the extract.11 | 300 mg of extract is not 300 mg of silicon. Look for the “Si” amount on the label. |
How much silicon should you take per day?
There is no recommended daily intake or tolerable upper intake level for silicon.1 This means that there is not enough data to set a limit, not that any amount can be taken.
As a guide, the German Federal Institute for Risk Assessment proposes no more than 10 mg of silicon in a single daily dose of a supplement (ch-OSA or MMST form), 100 mg (silicic acid gel) or 350 mg (silicon dioxide).6
Example. If you take a hair, skin and nails complex containing horsetail and also a separate silicon supplement, add up the amount from both products. One product is usually enough.
Who should be cautious?
Silicon obtained from food does not harm health.1 Speak to your doctor or pharmacist first about supplements if:
- you are pregnant or breastfeeding. Data are lacking, and horsetail preparations are not recommended during this period.11
- you want to give a supplement to a child. Horsetail preparations are not intended for children under 12 years of age.11
- you have kidney or heart disease. Horsetail preparations are not recommended if your doctor restricts your fluid intake.11
- you take medicines, especially diuretics.
When to see a doctor first. If your hair suddenly falls out heavily, bald patches appear or your nails change colour, the cause needs to be investigated first. A supplement will not solve it.
We remind you that a food supplement is not a substitute for a varied diet.12
Selected silicon products
Commercial information. These are products available in our shop. This is not an effectiveness ranking. Before buying, check the composition and the instructions for use on the product page.
Silica Complex with Horsetail Extract - 180 tablets - NOW Foods
Tablets with horsetail extract and 40 mg of silicon per tablet, plus calcium, zinc, manganese and boron. The manufacturer recommends 1–3 tablets per day.13
Bamboo Extract - N60 - Bamboo Extract - Swanson
Plant-based capsules with 300 mg of bamboo extract, standardised to 70% silicon. Take 1 capsule per day, from 18 years of age.14
Horsetail Extract, 2000mg - 30 ml - Nature's Answer
Liquid horsetail extract in drops, 2 ml 3 times per day. The amount of silicon in milligrams is not stated on the label.15
Vegan Hair, Skin & Nails - 90 vcaps - NOW Foods
A complex with 75 mg of horsetail extract, vitamins C and E, biotin, zinc, copper and MSM. If you take other mineral supplements, add up the amount of zinc.16
Frequently asked questions
Does silicon help with hair loss?
This has not been proven, which is why the EU does not allow such claims.2 If you are losing a lot of hair, see a doctor and have the cause investigated.
Which form of silicon is absorbed best?
In a comparative study, MMST was absorbed best (about 64%), ch-OSA about 17% and colloidal silicon about 1%.7 Better absorption does not yet mean proven benefit.
Do you get enough silicon from food?
For most people, yes. With an ordinary diet you get about 20–50 mg per day.1 Eat oats, wholegrain products and vegetables.
Scientific sources
- EFSA NDA Panel. Opinion related to the Tolerable Upper Intake Level of Silicon. EFSA Journal. 2004;60:1–11. efsa.europa.eu
- EFSA NDA Panel. Scientific Opinion on the substantiation of health claims related to silicon. EFSA Journal. 2011;9(6):2259. doi:10.2903/j.efsa.2011.2259
- EFSA ANS Panel. Calcium silicate and silicon dioxide/silicic acid gel added for nutritional purposes to food supplements. EFSA Journal. 2009;1132:1–24. doi:10.2903/j.efsa.2009.1132
- EFSA ANS Panel. Choline-stabilised orthosilicic acid added for nutritional purposes to food supplements. EFSA Journal. 2009;948:1–23. doi:10.2903/j.efsa.2009.948
- EFSA ANS Panel. Safety of organic silicon (monomethylsilanetriol, MMST) as a novel food ingredient. EFSA Journal. 2016;14(4):4436. doi:10.2903/j.efsa.2016.4436
- Bundesinstitut für Risikobewertung (BfR). Proposed maximum levels for the addition of silicon to foods including food supplements. 2021. bfr.bund.de
- Sripanyakorn S, Jugdaohsingh R, Dissayabutr W et al. The comparative absorption of silicon from different foods and food supplements. Br J Nutr. 2009;102(6):825–834. PMC2744664
- Powell JJ, McNaughton SA, Jugdaohsingh R et al. A provisional database for the silicon content of foods in the United Kingdom. Br J Nutr. 2005;94(5):804–812. PubMed
- Barel A, Calomme M, Timchenko A et al. Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair in women with photodamaged skin. Arch Dermatol Res. 2005;297(4):147–153. PubMed
- Spector TD, Calomme MR, Anderson SH et al. Choline-stabilized orthosilicic acid supplementation as an adjunct to calcium/vitamin D3 stimulates markers of bone formation in osteopenic females. BMC Musculoskelet Disord. 2008;9:85. doi:10.1186/1471-2474-9-85
- European Medicines Agency (EMA), HMPC. European Union herbal monograph on Equisetum arvense L., herba. EMA/HMPC/394894/2007. ema.europa.eu
- Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements. EUR-Lex
- NOW Foods. Silica Complex with Horsetail Extract, 180 tablets. Product label.
- Swanson. Bamboo Extract, 60 capsules. Product label.
- Nature's Answer. Horsetail Extract, 30 ml. Product label.
- NOW Foods. Vegan Hair, Skin & Nails, 90 capsules. Product label.
Disclaimer. This article is for informational purposes only and does not replace advice from a doctor or pharmacist. Food supplements are not intended to treat or prevent diseases and are not a substitute for a varied diet and a healthy lifestyle. Before taking supplements, especially during pregnancy or breastfeeding, if you have a chronic condition or if you take medicines, consult a healthcare professional.
