Silica supplements provide silicon, which is part of connective tissue. Labels give either the silicon amount or the weight of the extract, so enter the silicon (Si) first.
Calculator Official intake Study doses Best form Safety Sources
This is not an essential nutrient, so there is no official daily intake. Only study doses are shown.
These are doses tested in research, not personal advice. Some exceed the upper limit because they were short courses or given under medical care.
10 mg a day
In 48 women with fine hair, 10 mg silicon a day as ch-OSA for 9 months kept hair strength and elasticity better than placebo and increased hair thickness. One small trial.
10 mg a day
In 50 women with sun-damaged facial skin, 10 mg silicon a day as ch-OSA for 20 weeks reduced skin roughness and brittleness of hair and nails against placebo. One small trial.
6-12 mg a day
In 136 women with low bone density taking calcium and vitamin D, adding 3, 6 or 12 mg silicon a day as ch-OSA for a year raised one marker of bone formation at 6 and 12 mg, without a clear dose pattern. Bone density of the spine did not change.
Best form
Choline-stabilised orthosilicic acid (ch-OSA), silicon content
Why: All the human trials used choline-stabilised orthosilicic acid (ch-OSA) at 10 mg silicon a day. Compare the silicon content, not the weight of the extract.
Whole grains, oats, bananas and green beans. Beer is a notable source: silicon from beer was about 55% absorbed.
No important interactions known.
Neither EFSA nor the US has set an intake value or a safe limit for silicon. The trials reported no safety problems at 6 to 12 mg a day.
Pregnant, breastfeeding, on medication, or managing a health condition? Check with a doctor or pharmacist before starting a supplement.
Values checked: November 12, 2026.