Scientific Opinion on the substantiation of health claims related to silicon and protection against aluminium accumulation in the brain (ID 290), “cardiovascular health” (ID 289), forming a protective coat on the mucous membrane of the stomach (ID 345), neutralisation of gastric acid (ID 345), contribution to normal formation of collagen and connective tissue (ID 287, 288, 333, 334, 335, 1405, 1652, 1718, 1719, 1945), maintenance of normal bone (ID 287, 335, 1652, 1718, 1945), maintenance of normal joints (ID 1405, 1652, 1945), maintenance of normal appearance and elasticity of the skin (ID 288, 333), and contribution to normal formation of hair and nails (ID 334, 1652, 1719) pursuant to Article 13(1) of Regulation (EC) No 1924/2006