Although silicon dioxide is likely safe in moderate amounts, it can cause kidney stones in individuals who take silicon-containing antacids for long periods, states WebMD. The substance's safety when used in medicinal amounts is unknown as of 2015.
Although silicon dioxide is likely safe in food amounts for breastfeeding and pregnant women, these individuals should avoid using the substance in medicinal amounts due to lack of research concerning its safety, recommends WebMD. As a naturally occurring substance, silicon dioxide is found in the form of quartz and sand, and it is a natural part of the human diet, according to Drugs.com. The substance is considered safe by the Food and Drug Administration and is pharmacologically inactive.
As silicon dioxide's biological role has not been identified, there is no recommended daily allowance for the substance, explains WebMD. However, some research shows daily doses of 40 milligrams are linked with stronger bones in osteoporosis patients. Additionally, men and premenopausal women with higher silicon levels in their diet seem to have higher bone density than other individuals. Other claimed uses for silicon include hair loss, sprains, muscle strains, Alzheimer's disease and digestive problems, but insufficient evidence exists to confirm effectiveness in these cases. Individuals should consult their health care provider before taking silicon dioxide supplements.