Recent research has shown that diet alone may not be sufficient to supply the nutrients necessary for overall good health. While most experts agree that nutritional supplements are vital for a variety of illnesses, injuries, and age-related problems, vitamin and mineral supplements can also help to keep up optimal physical and psychological health, and promote longevity and chronic disease prevention.

  Ever since the term "vitamins" was coined almost one hundred years ago to describe the discovery of the essential life substances in foods, scientists have debated the issue of nutritional adequacy. Medical science has long held that healthy adults do not need supplementation if they consume a healthful, varied diet. Until recently, it was widely believed that supplements were only considered necessary if a person had an outright, or "severe", nutrient deficiency, usually manifested by overt illness.

  Nutritionist D. Lindsey Berkson, M.A., D.C., of Santa Fe, New Mexico, says, today, research indicates that people can have "mild" or "moderate" nutrient deficiencies, and that nutritional supplements are necessary to maintain health. These mild disorders may not cause tangible health disorders, making them difficult to diagnose, but can result in a variety of symptoms along with a general decrease in wellness. Unaddressed, these deficiencies can often put the body at risk for future health problems. Therefore, it is important for individuals to be sure they are receiving the proper amounts of nutrients for overall emotional and physical well-being.