Test Your Knowledge

All dietary supplements are intended to nutritionally supplement the diet and be taken by mouth. They can take many forms, including pill, tablet, capsule, liquids or powders. They may come in the form of energy bars or beverages – but these supplements are not intended or represented to be the sole item of a meal or diet. Certain supplements are available in lozenge or chewable form, although these often contain additional ingredients such as sugar to enhance their taste.

The dietary ingredients in supplements may include one or more of the following:

• Vitamins. A variety of organic substances that can be found in foods from plant and animal sources. Fourteen vitamins are essential for human metabolism, growth and development, and cell function. These are: vitamins A, C, D, E, K and the B vitamins (B6, B12, biotin, folate, niacin, pantothenic acid, riboflavin, choline and thiamine). All of these vitamins can be obtained from foods. Two of these may also be created by the human body under certain circumstances. Vitamin D can be created by the body after small amounts (e.g., 10 to 15 minutes) of exposure to sunlight. Vitamin K may be produced by bacteria in the intestines.
  
  Each vitamin has a specific effect in the body. For example, vitamins A, C and E act as antioxidants, which can help prevent damage to cells. Vitamin K helps blood clot and may help prevent hemorrhaging. Vitamins are either water soluble (vitamin C, B vitamins) or fat soluble (vitamin A, D, E, K). This affects whether the vitamin can be stored in body tissues or excreted by urine.
  
  Multivitamins contain a variety of vitamin types and are intended to be a convenient way to supplement the diet (usually one is taken per day) for normal healthy adults.  It is generally recommended that a multivitamin should contain 100 percent DRI (Dietary Reference Intake) or less for each ingredient. They may also contain certain minerals (e.g., calcium, iron, zinc).
  
  
• Minerals. A chemical element or compound found in trace amounts in a variety of foods. Minerals do not come from plant or animal sources, but rather from the earth (e.g., in the soil). Certain minerals are necessary in small amounts to help regulate body function and maintain good health. The human body does not produce minerals, so all minerals the body needs must be consumed, either in food or supplement form. Certain minerals (macrominerals) are required by the body in larger amounts than others (trace minerals).
  
  Different minerals have specific effects on the body. For example, iron is necessary for the production of red blood cells, calcium helps strengthen teeth and bones, and sodium helps regulate fluid levels in the body. While sodium is considered an essential mineral, it is not usually taken as a supplement because it is so common in foods and beverages.
  
  
• Herbal supplements or other botanicals. Plants or parts of plants used for cooking, tea and medicinal or therapeutic purposes. Some of these products have been used for hundreds of years, although scientific evidence of their efficacy and safety is rarely conclusive. Herbs may be associated with a wide range of effects on the body. Examples of these types of dietary ingredients include echinacea, ephedra, ginkgo biloba, ginseng and St. John’s wort.
  
  
• Other substances found in supplements include:
  
  
• • Amino acids (e.g., branched chain amino acids)
    
    
  • Enzymes and hormones (e.g., coenzyme Q10, DHEA, melatonin)
    
    
  • Ergogenic aids (e.g., chromium picolinate, creatine)
    
    
  • Glucosamine and chondroitin (supplements for certain painful conditions)
    
    
  • Phytochemicals (e.g., carotenoids, beta-carotene)
    
    
  • Probiotics (e.g., lactobacillus acidophilus)
    
    
  • Zoochemicals (non-nutrient chemicals from animal sources, such as conjugated linoleic acid)
    
    
  • Omega-3 fatty acids (e.g., fish oil, flaxseed)
    
    
  • Soluble fiber (e.g., psyllium)
    
    
  • Spirulina (e.g. blue green algae)
    
    
  • Tissue (e.g., shark or bovine cartilage)