Dietary Reference Intakes (DRIs): Foundations and Applications in Nutrition

Dietary Reference Intakes (DRIs)

Introduction to DRIs

Dietary Reference Intakes (DRIs) are a set of reference values used to assess and plan nutrient intakes for healthy individuals. Developed by the National Academies of Sciences, DRIs provide specific recommendations for nutrients and caloric intake based on scientific evidence.

• Purpose: To guide nutrition planning and policy for individuals and populations.

• Application: Used in health care, research, and public health settings.

• Variation: Recommendations vary by age, sex, life stage (e.g., pregnancy, lactation).

Example: DRIs are used to set daily values on food labels and inform dietary guidelines.

DRIs vs. Dietary Guidelines for Americans (DGAs)

DRIs and DGAs are both important tools in nutrition, but they serve different purposes and are developed by different organizations.

DRIs	DGAs	Both
Developed by an independent organization	Developed by the federal government	Provide specific recommendations for nutrient and caloric intake
Focus on micronutrients (vitamins, minerals)	Focus on macronutrients and energy intake	Used in nutrition research and policy

Example: DGAs provide general eating patterns, while DRIs give specific nutrient targets.

Types of Dietary Reference Intakes

Key DRI Terms and Definitions

• Recommended Dietary Allowance (RDA): The average daily intake level sufficient to meet the nutrient requirements of nearly all (97–98%) healthy individuals in a particular life stage and gender group.

• Adequate Intake (AI): Established when evidence is insufficient to develop an RDA; a recommended intake level based on observed or experimentally determined estimates.

• Tolerable Upper Intake Level (UL): The highest daily intake level likely to pose no risk of adverse health effects for almost all individuals.

• Estimated Average Requirement (EAR): The intake level estimated to meet the needs of 50% of individuals in a group.

• Chronic Disease Risk Reduction Intake (CDRR): Intake level associated with reduced risk of chronic disease.

Example: If the RDA for vitamin C is 90 mg for adult men, this amount meets the needs of nearly all healthy adult men.

DRI Decision Tree

DRIs are selected based on available scientific evidence and population needs. The hierarchy is as follows:

• If sufficient evidence exists, set an RDA.

• If not, set an AI.

• Set a UL to prevent toxicity.

• Set a CDRR if evidence links intake to chronic disease risk.

Formula: For EAR calculation:

$EAR = \text{Amount that meets needs of 50% of individuals}$

Dietary Reference Intakes for Energy & Macronutrients

Energy Intake and Measurement

Energy requirements are estimated based on age, sex, weight, height, and physical activity level.

• Estimated Energy Requirement (EER): The average dietary energy intake predicted to maintain energy balance in a healthy adult.

• Calculation: EER is calculated using equations that factor in age, sex, weight, height, and activity level.

Formula:

$EER = \text{Estimated number of Calories needed}$

Acceptable Macronutrient Distribution Range (AMDR)

AMDR defines the recommended percentage of total energy intake that should come from each macronutrient.

Macronutrient	Recommended Range (% of total Calories)
Carbohydrates	45–65%
Fat	20–35%
Protein	10–35%

Example: For a person consuming 2,000 Calories per day, 900–1,300 Calories should come from carbohydrates.

AMDR vs. MyPlate

AMDR recommendations are based on macronutrient percentages, while MyPlate focuses on food groups.

• AMDR: Provides ranges for carbohydrate, fat, and protein intake.

• MyPlate: Offers guidance based on food types and portions.

Example: AMDR may recommend 45–65% of Calories from carbohydrates, while MyPlate suggests filling half your plate with fruits and vegetables.

Application and Practice

Using DRIs in Dietary Planning

DRIs are used to assess nutrient adequacy, plan diets, and set public health policies.

• Choose the appropriate DRI based on the nutrient and population.

• Use EER for energy planning, AMDR for macronutrient distribution, and RDA/AI/UL for micronutrients.

Example: When planning a diet for a child, use age-appropriate RDAs and AMDRs to ensure balanced nutrition.

Additional info: DRIs are updated periodically as new research emerges, and are foundational for nutrition professionals in clinical and public health settings.