Concepts and Definitions in Relation to Nutrient Requirements
1) The probability concept describes the relationship between the levels of intake and the probability of risk of inadequate and excess intakes.
2) The range of intake in which there is zero probability of risk of deficiency and risk of excess is known as the safe requirement range.
3) Age, sex and body weight are determinants of nutrient requirements.
4) Nutrient requirements vary for different individuals due to genetic differences. The individual variations are described by the term coefficient of variation which is the standard deviation expressed as a percent of the mean requirement.
5) Mean +2 SD is the recommended allowance for a nutrient, which meets the needs of 97 to 98% of the individuals in a life stage and gender group. For energy only the mean is taken as the RDA.
6) Bioavailability of nutrients must be taken into account while making recommendations for nutrient requirements.
7) The basic terms used in relation to nutrient requirements are minimum requirements, safe allowances, recommended dietary allowances, dietary reference intakes.