The vitamins in Geritol® multivitamin are synthetic, but they are as safe and bio-available as naturally derived vitamins. However, the minerals in Geritol® are not synthetic. (It is not possible to synthesize a mineral.)
All of the minerals are from natural sources and are, of course, purified. The minerals in all Geritol® products are derived from mineral salts, with the exception of iron. Iron is supplied in its purest form, carbonyl iron. Some of the inorganic salts used are potassium iodide (iodine), sodium metavanadate (valadium), and magnesium oxide.