What are dris and why are they preferred? why are they not on food labels?

DRIs is the general term for a set of reference values or guidelines that are used to plan and asses nutrient intakes of healthy people. These values which vary by age and gender include: 

- Recommended Dietary allowance (RDA): average daily level of intake sufficient to meet nutrient requirements of about 97 - 98% of healthy people.

-Adequate intake (AI): established when evidence is not sufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy.

- Tolerable Upper Intake (UL): Maximum daily intake unlikely to cause adverse health  effects.

DRIs are not necessarily found on labels because there is no law requiring that they must be placed there.

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