silicon
Also known as: Silicon, Si, silica, silicic acid, orthosilicic acid, monomethylsilanetriol, MMST, sodium metasilicate
Overview
Silicon (Si) is a metalloid trace mineral found abundantly in soil, water, and various foods such as whole grains and vegetables. While not officially classified as an essential nutrient for humans, it is considered beneficial for bone and connective tissue health. The body does not synthesize silicon, so it must be obtained through diet or supplementation. Supplemental forms like orthosilicic acid and monomethylsilanetriol (MMST) are preferred due to their higher bioavailability compared to dietary silicon. Research primarily investigates silicon's role in bone health, collagen synthesis, and connective tissue integrity, with emerging studies exploring its potential in glycemic control, cardiovascular health, and neurological protection. The current research maturity level is moderate, with most evidence derived from animal models and small human trials, indicating a need for more extensive human studies.
Benefits
Silicon supplementation, particularly with orthosilicic acid and MMST, has shown potential benefits for bone health. Animal studies consistently demonstrate improved bone mineral density (BMD) and bone strength. Human trials, though limited, suggest similar benefits at doses around 25 mg/day, with one randomized controlled trial showing that 10.5 mg/day of MMST increased serum and urinary silicon without adverse effects. These benefits are thought to be most relevant for postmenopausal women and older adults at risk for osteoporosis, although robust clinical evidence in humans is still lacking. Beyond bone health, animal studies indicate silicon may improve glycemic control and lipid profiles, suggesting potential anti-diabetic and anti-atherogenic effects. Observational data also hint at a possible link between higher silicon intake and a reduced risk of Alzheimer's disease, but this requires further causal investigation. The effect sizes observed in bone health are modest, and clinical significance in humans remains uncertain due to the scarcity of high-quality, large-scale randomized controlled trials.
How it works
Silicon's primary mechanism of action involves its incorporation into the bone matrix, where it plays a crucial role in supporting collagen synthesis and mineralization. It is believed to upregulate osteoblast activity, which are cells responsible for bone formation, and inhibit osteoclast resorption, which are cells that break down bone. This dual action contributes to maintaining bone integrity and strength. Beyond the skeletal system, emerging research suggests silicon interacts with glucose and lipid metabolism, potentially through pathways involving liver X receptor (LXR) and ABCG5/8 transporters. The absorption and bioavailability of silicon are highly dependent on its chemical form, with orthosilicic acid and MMST being recognized as highly bioavailable forms, allowing for efficient uptake and utilization by the body.
Side effects
Silicon is generally considered safe when consumed at typical supplemental doses, usually up to 50 mg/day. Short-term human trials have not reported any serious adverse effects. There are no commonly reported side effects (occurring in more than 5% of users), uncommon side effects (1-5%), or rare side effects (less than 1%) documented in controlled trials. No significant drug interactions have been identified, and there are no established contraindications for silicon supplementation. However, it is important to note that long-term safety data are currently lacking, as most studies have been of short duration. Furthermore, the safety of silicon supplementation in specific populations such as pregnant or lactating women and children has not been established, and caution is advised in these groups.
Dosage
The minimum effective dose for silicon is not well-established, but human studies suggest potential benefits for bone health at approximately 10–25 mg/day. This range is also considered the optimal dosage for bone health, as higher doses have not demonstrated additional benefits and their long-term safety is not yet confirmed. A maximum safe dose has not been definitively established, but doses exceeding 50 mg/day have not been adequately studied in humans. There are no specific timing recommendations for silicon supplementation, with daily dosing being the typical approach. For optimal bioavailability, orthosilicic acid and monomethylsilanetriol (MMST) are the preferred forms. Absorption may be enhanced when taken on an empty stomach, and co-administration with calcium and vitamin D may offer synergistic benefits for bone health.
FAQs
Is silicon supplementation safe for long-term use?
Short-term use of silicon at typical doses appears safe, but long-term safety data are currently lacking. More research is needed to confirm its safety over extended periods.
What is the best way to take silicon supplements?
Daily dosing is typical, and forms like orthosilicic acid and MMST are preferred for their high bioavailability. Taking it on an empty stomach may enhance absorption.
Can silicon replace calcium or vitamin D for bone health?
No, silicon is not a substitute for calcium or vitamin D. Its benefits for bone health are considered adjunctive, meaning it may support these essential nutrients but not replace them.
What kind of results can I expect from silicon supplementation?
You might see modest improvements in bone markers. However, robust clinical benefits like a reduction in fracture risk have not yet been definitively demonstrated in human trials.
Are there any known drug interactions with silicon?
Currently, there are no known significant drug interactions with silicon supplementation. However, it's always advisable to consult with a healthcare professional if you are taking other medications.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10857027/ – This animal study investigated the effects of silicon (as sodium metasilicate) on bone health in rats. It found that silicon decreased bone resorption markers and increased magnesium in low-calcium conditions, but surprisingly reduced BMD in high-calcium conditions. The study concluded that tibia strength improved with adequate calcium, highlighting the complex interaction between silicon and calcium.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC8283247/ – This human randomized controlled trial examined the bioavailability and safety of monomethylsilanetriol (MMST) in healthy women. It demonstrated a significant increase in serum and urinary silicon levels after 4 weeks of 10.5 mg/day MMST supplementation, with no reported adverse effects. The study confirmed MMST's good bioavailability and short-term safety, though it was not powered for clinical outcomes.
- https://apcz.umk.pl/QS/article/download/56079/40493/165896 – This animal study explored the effects of chelated silica on bone formation markers in mice and rats. It reported an increase in alkaline phosphatase (a bone formation marker) in mice, but inconsistent findings in rats and no other significant differences compared to controls. The study contributes to the safety profile but has limited direct clinical relevance due to its animal model and inconsistent results.
- https://pdfs.semanticscholar.org/4cf6/f7408ae3f9255d25065995f24da0ccaaa29e.pdf – This review discusses the role of silicon in human health, particularly its potential benefits for bone and connective tissue. It highlights silicon's involvement in collagen synthesis and bone mineralization, and touches upon emerging research areas like glycemic control and neurological protection. The review emphasizes the need for more robust human data to confirm these benefits.
- https://academic.oup.com/nutritionreviews/article-abstract/69/1/41/1844514 – This review article provides an overview of silicon's role as a beneficial trace element, particularly in bone health. It discusses the evidence supporting silicon's involvement in bone formation and maintenance, and the bioavailability of different silicon forms. The article underscores the importance of silicon for optimal skeletal health, despite its non-essential classification.
- https://onlinelibrary.wiley.com/doi/10.1155/2013/316783 – This review focuses on the importance of silicon for bone and connective tissue health. It details how silicon contributes to the structural integrity of these tissues by influencing collagen synthesis and mineralization processes. The review also discusses the various forms of silicon and their absorption, emphasizing the need for adequate intake for maintaining healthy bones and joints.
