You can make wiser choices when purchasing vitamins by learning to identify synthetic dietary supplements from natural vitamin products. Manufacturers of dietary supplements sometimes use synthetic materials for increasing the vitamin’s potency and stability. According to the Organic Consumers Association, some of these materials come from coal tar derivatives, the same toxins that cause throat cancer in tobacco smokers. Before shopping for vitamin supplements, know what to look for in a vitamin product that may cause harm to your health. Click LIVESTRONG.COM.