Q. Can you explain the reason nutritional products often contain higher levels of nutrients than are listed in the RDA?

A. The RDA (Recommended Dietary Allowances) are broad guidelines established by the Food and Nutrition Board of the National Academy of Sciences/National Research Council. Based on an intake of about 2000 calories per day, dosages are designed to prevent definite deficiency conditions (e.g., scurvy, pellagra, beriberi) not to promote optimum health.

RDA guidelines do not, however, take into account variations for individual needs, eating patterns, or conditions that place people at increased risk for deficiencies.