Silica is a trace mineral which contributes to the strength of connective tissue. Connective tissue is what holds the body together. It includes muscles, tendons, ligaments, cartilage and bone. Without silica, connective tissue would not be properly constructed, leaving it impaired. Food sources of silica include leeks, green beans, garbanzo beans, strawberries, cucumber, mango, celery, asparagus and rhubarb.