How Does the Body Get Silica? Sources and Absorption

December 18, 2025 •

5 min read

According to research, the body absorbs silicon, the active component of silica, most efficiently through water and other fluids. In contrast to the popular perception that silica-rich foods are the best source, the body's absorption depends heavily on the mineral's chemical form.

Quick Summary

The body primarily obtains silica through diet, beverages, and supplements, with bioavailability varying significantly by source. The easily absorbed form is orthosilicic acid, found in water and beer, while some plant-based foods, despite being high in silica, offer poor absorption.

Key Points

Source vs. Bioavailability: The amount of silica a food contains is less important than its bioavailability. The body best absorbs water-soluble orthosilicic acid, while poorly absorbed polymerized forms are common in many plant foods.
Top Dietary Sources: Water is a highly bioavailable source of silica. Other good dietary sources include whole grains like oats and barley, along with vegetables such as green beans and lentils.
Supplement Absorption: Supplemental silica varies widely in absorption. Choline-stabilized orthosilicic acid (ch-OSA) and monomethylsilanetriol (MMST) are highly absorbable forms, unlike colloidal silica or magnesium trisilicate.
Collagen and Bone Health: Silica is crucial for collagen formation, which is vital for skin elasticity, healthy hair and nails, and strong connective tissues. It also plays a key role in the bone mineralization process.
Excretion and Safety: The body efficiently excretes excess water-soluble silica through the kidneys, making it unlikely for healthy individuals to accumulate toxic levels from dietary intake or moderate supplementation.
Aging and Intake: As we age, the body's natural collagen production decreases. This is often cited as a reason to consider supplemental silica to support connective tissue and bone health.

The Importance of Bioavailability in Silica Absorption

Silicon, in the form of silica, is the second most abundant element in the Earth's crust, found in soil, rocks, and water. For the human body, its absorption is less about total intake and more about the compound's solubility and chemical form. The body requires a water-soluble form, specifically orthosilicic acid (OSA), to absorb it efficiently. Many plant-based food sources contain silica in a poorly absorbed, polymerized form, whereas sources like water and certain supplements deliver it in the bioavailable monomeric state.

Dietary Sources of Bioavailable Silica

Getting silica from your diet requires focusing on sources where the mineral is present in a form that the body can readily use. This can be achieved through both solid foods and beverages.

Vegetables, Grains, and Fruits

While most plant-based foods contain silica, their bioavailability varies significantly. Whole grains like oats and barley, along with vegetables such as green beans and lentils, offer some of the most readily absorbed forms from food. The polymerization of silica during the plant's growth cycle can hinder absorption, which is why a food's total silica content isn't a reliable indicator of its benefit. For example, bananas are high in total silica, but the body absorbs very little of it.

Whole Grains: Oats, barley, and whole wheat are consistently cited as excellent dietary sources.
Green Beans: This vegetable is noted for having relatively good silica absorption compared to other plant sources.
Leafy Greens: Spinach and kale provide silica along with other vital nutrients for connective tissue health.
Lentils: Red lentils contain a significant amount of silica, contributing to overall intake.

Beverages

Perhaps surprisingly, beverages are one of the most effective delivery systems for bioavailable silica, as the mineral is often in the soluble orthosilicic acid form.

Drinking Water: The silica content in water depends on its geological source, but it is one of the most readily available and absorbable sources, with absorption rates of at least 50%. Hard water generally has higher silica levels than soft water.
Beer: The brewing process releases soluble orthosilicic acid from barley and hops, making beer a notable, though not recommended as a primary source, for absorbable silica.
Herbal Teas: Horsetail and nettle teas are traditional remedies known for their high silica content. The brewing process helps release the soluble compound for absorption.

Supplementation for Optimal Silica Intake

For many, especially as they age and collagen production declines, dietary intake might be insufficient to meet health goals. This is where targeted supplementation becomes a consideration, with a strong emphasis on absorbable forms.

Forms of Supplemental Silica

Not all silica supplements are created equal, and the key difference lies in their bioavailability.

Choline-Stabilized Orthosilicic Acid (ch-OSA): This is one of the most clinically studied and highly bioavailable forms of supplemental silica. The choline stabilizes the orthosilicic acid, preventing it from polymerizing and ensuring high absorption.
Monomethylsilanetriol (MMST): Another highly bioavailable organic silicon compound that is effective and used in supplements, particularly in liquid form.
Colloidal Silica & Silicon Dioxide: These forms are significantly less bioavailable. They contain larger, polymerized silica particles that are not easily absorbed by the body and mostly pass through the digestive system.
Diatomaceous Earth (Amorphous): Food-grade amorphous diatomaceous earth is comprised of amorphous silica. While largely insoluble, the body can convert some of it to the absorbable OSA form upon hydration.

Natural vs. Supplemental Silica: A Comparison


Feature	Natural Dietary Silica (e.g., from grains)	Supplemental Silica (e.g., ch-OSA)
Form	Primarily polymerized silica (phytoliths), requiring enzymatic breakdown.	Stabilized orthosilicic acid, a small, highly soluble monomer.
Absorption Rate	Variable and often lower; dependent on the food's specific chemical form.	High; designed for maximum intestinal absorption.
Consistency	Varies widely based on food processing, type of food, and preparation methods.	Standardized and consistent dosage, ensuring a reliable intake of bioavailable silicon.
Targeted Use	Part of a balanced diet; general mineral intake.	Focused approach for specific health goals, such as boosting collagen for skin, hair, and nail health.

Conclusion

The body gets silica primarily through dietary sources, including water, food, and supplements. However, the quantity of total silica is not as important as its bioavailability, which depends on the form of the compound ingested. The most effective sources provide silica in the water-soluble form of orthosilicic acid. While foods like whole grains and green beans contribute to intake, water and advanced supplements like ch-OSA offer the most readily absorbable forms, especially for those with specific health goals related to bone health and connective tissue strength. Understanding these differences helps in making informed decisions about how to best ensure adequate silica for overall health and well-being.

Why is silica needed for healthy bones and skin?

Silica plays a crucial role in collagen production, which provides the framework for healthy skin and connective tissues. For bones, it is essential for the mineralization process, helping deposit calcium for increased bone density. Adequate silica intake supports the strength and integrity of these tissues, which can decline with age.

What are the most bioavailable forms of supplemental silica?

The most bioavailable forms are supplements containing stabilized orthosilicic acid (OSA), such as choline-stabilized orthosilicic acid (ch-OSA) or monomethylsilanetriol (MMST). These forms are designed for high absorption in the gut.

Is the silica found in bananas well-absorbed by the body?

No, despite being high in total silica, the silicon in bananas is in a polymerized form that is poorly absorbed by the body, with studies showing less than 5% absorption.

Can food processing affect the silica content of food?

Yes, modern food processing methods, particularly the refining of grains, can significantly reduce the amount of silica in food products. Unrefined, whole grains are a much better source of the mineral.

Can you get too much silica from your diet?

It is uncommon to overdose on silica through diet alone, as the body effectively excretes excess water-soluble forms through the kidneys. However, it is always recommended to follow dosage instructions for supplements.

What are the signs of silica deficiency?

Since silica plays a role in collagen and bone formation, deficiency may manifest in brittle nails, hair loss, and weakened connective tissue. However, further research is needed to fully understand silicon's essential role in humans.

Is inhaling silica dust dangerous?

Yes, inhaling crystalline silica dust (from materials like sand, concrete, and rock) is very dangerous and can cause severe lung diseases like silicosis. This is distinct from consuming dietary silica, which is safe.

Frequently Asked Questions

The body acquires silica primarily through diet, which includes foods, beverages like water and beer, and dietary supplements. Its absorption depends on the chemical form, with water-soluble forms like orthosilicic acid being most readily absorbed.

Orthosilicic acid (OSA) is the major water-soluble and highly absorbable form of silicon. It is the form that the body can readily use, and it is found predominantly in water and some beverages. Supplemental forms are often stabilized to maintain this structure for optimal absorption.

No, the bioavailability of silica varies significantly among different foods. For instance, while bananas contain high total silica, the mineral is in a poorly absorbed, polymerized form. In contrast, whole grains and green beans offer more absorbable silica.

Yes, high-quality silica supplements, particularly those containing stabilized orthosilicic acid (ch-OSA, MMST), offer a more concentrated and consistently bioavailable form than many food sources, making them a very efficient way to increase intake.

While the brewing process makes silica in beer more bioavailable, moderate beer consumption is not recommended as a primary health strategy. A non-alcoholic option would provide the benefits without the risks of alcohol.

Silicon is the basic element (Si), while silica (silicon dioxide, SiO2) is a compound of silicon and oxygen. In the body, silicon exists primarily as orthosilicic acid. The terms are often used interchangeably, but context is important, especially regarding industrial versus dietary forms.

Silica is believed to promote healthy skin, hair, and nails by playing a role in collagen synthesis and connective tissue formation. Studies suggest supplementation can lead to improvements in hair strength, skin elasticity, and nail brittleness.