Silicon and Bone Density
James Meschino DC, MS, ROHP
A number of supplement manufacturers have begun adding silicon to formulations intended to help preserve bone density. It may appear in these formulations as silica (silicon dioxide), sodium metasilicate and silicic acid. The average intake from food is 20-50 mg per day on average, in North America. Silicon has been shown to be highly bioavailable and evidence continues to accumulate implicating its role in bone formation. Studies of silicon deprivation in growing animals conducted in the early 1970’s showed reduced growth and marked defects of bone and connective tissue. In addition, silicon supplementation of postmenopausal women with osteoporosis not only inhibits bone resorption, but also increases trabecular bone volume and bone mineral density. These results are supported by the ovariectomized rat model of postmenopausal osteoporosis, in which oral silicon completely abrogates the loss of bone mass. Recently, R. Jugdaohsingh et al, showed in osteoblasticcell lines and human bone marrow stromal cells in vitro, that physiologic concentrations of orthosilicic acid increase the synthesis of bone markers including type I collagen, the major organic component of bone matrix, and may also be involved in the mineralization of bone matrix.
In support of this evidence, Asians and Indians have much higher silicon intakes than do Western populations as a result of their higher intakes of plant-based foods. These populations have been shown to have a lower incidence of hip fractures than occurs in Western populations. Silicon has been shown to be very non-toxic and when taken as a supplement with other bone support nutrients, may be an important mineral in the prevention of osteoporosis. As an aside, silicon is the most abundant mineral in the earth’s crust and is found in the body within bone, blood vessels, cartilage, tendons, skin and hair.
Jugdaohsingh R et al, Dietary silicon intake and absorption. Am J ClinNutr. 2002; 75: 887-93