How to Calculate Your DRI: A Step-by-Step Guide to Personalized Nutrition

January 8, 2026 •

3 min read

According to the National Academies of Sciences, Engineering, and Medicine, Dietary Reference Intakes (DRIs) are a set of reference values used to plan and assess nutrient intakes of healthy people. Knowing how to calculate your DRI is a powerful tool for customizing your nutritional approach and achieving specific health goals.

Quick Summary

A personal Dietary Reference Intake is determined by calculating estimated daily energy needs, then breaking down macronutrient requirements and consulting official tables for specific vitamin and mineral recommendations based on age and sex.

Key Points

Start with the EER: Begin your calculation by determining your Estimated Energy Requirement (EER) based on your age, sex, weight, height, and physical activity level.
Use AMDRs for Macronutrients: Use the Acceptable Macronutrient Distribution Ranges (AMDRs) to calculate your protein, fat, and carbohydrate intake ranges based on your EER.
Consult Official Tables for Micronutrients: Refer to authoritative sources like the National Institutes of Health for specific Recommended Dietary Allowances (RDAs) and Adequate Intakes (AIs) for vitamins and minerals based on your demographic.
Understand the DRI Components: Recognize the differences between EAR, RDA, AI, and UL to apply the correct reference value when planning your diet.
Account for Individual Factors: Remember that DRIs are for healthy populations. Adjustments may be needed for specific health conditions, and personalizing the recommendations with a professional is often necessary.
Stay Within Tolerable Upper Intake Levels: Be mindful of the UL to avoid potential adverse health effects from excessive intake of certain nutrients.

Understanding the Components of DRI

Before you calculate your DRI, it's essential to understand its various components. The term 'DRI' is an umbrella term that includes several different values, each serving a unique purpose in nutritional assessment and planning. These include the Estimated Average Requirement (EAR), Recommended Dietary Allowance (RDA), Adequate Intake (AI), Tolerable Upper Intake Level (UL), Estimated Energy Requirement (EER), and Acceptable Macronutrient Distribution Range (AMDR). The EAR is the average daily intake meeting the needs of 50% of a group, while the RDA is sufficient for 97-98%. AI is used when there's not enough data for an EAR/RDA. The UL is the highest intake level unlikely to cause adverse effects. EER is the average energy intake to maintain balance in a healthy adult. AMDR is the range of intake for macronutrients associated with reduced chronic disease risk.

Step-by-Step Guide to Calculate Your DRI

Calculating your complete DRI requires a multi-step process. You will need a calculator, a tape measure, and a scale.

Step 1: Determine Your DRI Category

Nutrient requirements vary with age, sex, and life stage. Identify your category based on these factors to use the correct formulas and nutrient tables. Consider your age group (e.g., 19-30), sex, and any special conditions like pregnancy or lactation.

Step 2: Calculate Your Estimated Energy Requirement (EER)

Your EER determines your total daily caloric needs. For adults aged 19 and over, use these formulas from the Institute of Medicine:

For adult men: EER (kcal/day) = 662 - (9.53 × age [y]) + PA × (15.91 × weight [kg] + 539.6 × height [m])

For adult women: EER (kcal/day) = 354 - (6.91 × age [y]) + PA × (9.36 × weight [kg] + 726 × height [m])

PA is the Physical Activity coefficient:

Sedentary (PA = 1.00): Little to no exercise.
Low Active (PA = 1.11 for men, 1.12 for women): Light exercise/sports 1-3 days/week.
Active (PA = 1.25 for men, 1.27 for women): Moderate exercise/sports 3-5 days/week.
Very Active (PA = 1.48 for men, 1.45 for women): Hard exercise/sports 6-7 days a week.

Step 3: Determine Your Macronutrient Needs (AMDRs)

Calculate the recommended range for each macronutrient using the AMDRs based on your EER.

Protein: 10–35% of total calories. Protein (grams) = (EER × Recommended %)/4
Fat: 20–35% of total calories. Fat (grams) = (EER × Recommended %)/9
Carbohydrates: 45–65% of total calories. Carbohydrates (grams) = (EER × Recommended %)/4

Step 4: Find Your Micronutrient DRIs (Vitamins and Minerals)

Micronutrient needs are found by consulting official DRI tables from sources like the NIH or Health Canada. These tables provide RDA, AI, and UL values for your age and sex group. For comprehensive data, visit the NIH Office of Dietary Supplements website.

Example Calculation: An Active 30-Year-Old Woman

Let's calculate the DRI for a 30-year-old woman who is 165 cm tall (1.65 m), weighs 63 kg, and is active (PA=1.27).

EER Calculation: Using the formula, her EER is approximately 2417 kcal/day.
Macronutrient Ranges (Using Mid-Range Values): Based on a 2417 kcal EER and mid-range AMDRs, her approximate macronutrient needs are: Protein: 136 grams/day, Fat: 74 grams/day, Carbohydrates: 332 grams/day.
Micronutrient Reference: Consult official tables for the 19-30 age group, female category, for specific RDA and UL values for vitamins and minerals.

Comparing DRI Value Types

Different DRI values serve different purposes.


Feature	Recommended Dietary Allowance (RDA)	Adequate Intake (AI)	Tolerable Upper Intake Level (UL)
Basis	Scientific evidence.	Best estimate when RDA data is insufficient.	Risk assessment.
Purpose	Goal for daily intake to prevent deficiency.	Goal for individual intake, assumed adequate.	Prevent toxicity from overconsumption.
Scope	Covers nearly all (97-98%) healthy individuals.	Covers apparently healthy people.	Covers almost all individuals in the general population.

Limitations and Important Considerations

DRIs are guidelines for healthy people and don't factor in medical conditions or individual variations. Physical activity also significantly impacts EER, and accurately estimating it can be difficult. For personalized nutritional advice, consult a registered dietitian or healthcare professional.

Conclusion

Calculating your DRI involves determining your EER, distributing macronutrients using AMDRs, and finding micronutrient values in authoritative tables based on your age, sex, and life stage. This process provides a scientific basis for creating a personalized and informed nutrition plan, helping you meet your body's specific needs for optimal health.

Frequently Asked Questions

DRI, or Dietary Reference Intake, is a comprehensive set of reference values that includes RDA (Recommended Dietary Allowance). RDA is a specific value within the DRI framework, representing the intake level sufficient to meet the needs of 97-98% of healthy people in a group.

Official DRI tables are published by health organizations. The U.S. National Institutes of Health (NIH) provides access to these tables on its Office of Dietary Supplements website. Health Canada also provides similar resources online.

DRIs are designed for apparently healthy individuals. They may not be appropriate for people with specific medical conditions that affect nutrient absorption, metabolism, or requirements. Consulting a healthcare professional is best for personalized advice.

The PA coefficient is a numerical value assigned based on your level of daily activity. You can choose the appropriate category (sedentary, low active, active, or very active) based on your exercise habits when using the EER formula.

In cases where insufficient scientific evidence exists to determine an RDA, an Adequate Intake (AI) value is provided instead. The AI is a recommended intake level based on observed averages in healthy populations.

The UL is important because it establishes the maximum daily nutrient intake level that is unlikely to cause adverse health effects. It serves as a safety guide, particularly when considering nutrient supplements.

Pregnancy and lactation are specific life stages with increased nutrient and energy needs. Special formulas exist for EER during these periods, and separate DRI tables provide specific RDA or AI values for key nutrients.