Skip to main content

Clear filters



DRV vs RDA vs NRV vs PRI: nutrition reference intakes explained

10 March 2021

Back to article list

Filter articles

By Sarah Dumont-Gale

A balanced diet is one that includes protein, carbohydrate, fat, fibre, vitamins, minerals and water. Every one of these nutrients is required by the human body to function, but exactly how much do we need of each for good health?

Several committees and authorities have defined various nutrient and energy criteria as a guide for the general population as to what to consume daily to maintain health and prevent deficiency.

The nutrient and energy criteria are often shortened to acronyms such as DRV or RDA, and it can be confusing knowing what figures are relevant to you, especially as many of the terms have been superseded by updated ones. This article will clear up some of the confusion around the various nutritional acronyms to help you reach your nutritional goals.

What are Dietary Reference Values (DRVs)?

Dietary Reference Values are estimates of the energy and nutritional requirements of different groups of healthy people in the Irish population.

There are different DRVs for different ages and genders, plus separate advice for pregnant and breastfeeding women.

DRVs are not recommendations or goals, simply the estimated requirement of a particular population group to prevent deficiency and stay healthy.

DRVs can be split out to include Average Requirements (ARs), Population Reference Intakes (PRIs), Adequate Intake (AI) and Reference Intake range (RI). p>

Smiling pregnant woman holding her stomach

Dietary Reference Values are different for different ages and genders – and there is separate advice for pregnant and breastfeeding women.

Average Requirements: AR

AR is the level of (nutrient) intake estimated to satisfy the physiological requirement or metabolic demand in half of the people in a population group. 1

This means that approximately 50 per cent of a group will require less and 50 per cent will require more.


The ARs for energy requirements were updated by EFSA in 2010.

Population Reference Intakes: PRIs

PRI is the amount of a nutrient required for 97.5 per cent of the population to be healthy. Generally, the PRI should be used when assessing the dietary intake of a population group, as the nearer the average intake of the group is to the PRI, the less likely it is that any individual will be deficient. 1

Adequate Intake: AI

AI is the value estimated when a PRI cannot be established because an AR cannot be determined. An Adequate Intake is the average observed or experimentally determined approximations or estimates of nutrient intake by a population group (or groups) of apparently healthy people that is assumed to be adequate.

What about Reference Intakes (RIs)?

Reference Intakes are the intake range for macronutrients, expressed as a percentage of the energy intake. These apply to ranges of intakes that are adequate for maintaining health and associated with a low risk of selected chronic diseases. 1

RIs have been set for calories, protein, carbohydrate, sugars, fat, saturated fat, fibre and salt.

RIs are not targets, but a guideline or benchmark to help advise the maximum number of calories or amount of key nutrients to consume in a day. They help to guide healthy dietary choices and provide a framework to consume a balanced daily intake.

Personalised requirements will vary depending on age, gender and level of physical activity. There is currently no RI that can be used specifically for children.

Where do Nutrient Reference Values (NRVs) fit in?

Nutrient Reference Values (NRVs) are set for vitamins and minerals for the purpose of food labelling based on food legislation. NRVs used to be known as Recommended Daily Allowance (RDA), and although the name has changed, the values have stayed the same.

The nutrient reference values (NRVs) on food labels differ from DRVs. NRVs are generic values for nutrients and are not specific for age and gender. The only exception to this are the labels of certain foods aimed at infants and young children, for which age-appropriate NRVs are used.

NRVs are the level of a nutrient that is considered adequate to meet the nutritional requirements of an average healthy adult to prevent deficiency. There is only one NRV for each nutrient. Food supplement labels list the quantity of a nutrient alongside the percentage of the NRV value.

The US has its own version of the NRVs called the Daily Value (DV). Different criteria were used to define NRVs and DVs, which is why you will see a difference between the NRVs and US DVs.

What are Tolerable Upper Limits?

The European Food Safety Authority (EFSA) has provided guidance on safe intake levels known as Tolerable Upper Intake Levels (UL). The UL is defined as the maximum level of long-term daily intake of a nutrient, from all sources, judged unlikely to cause adverse health effects in the general population.

Wooden spoons with different vitamins in them

Safe Upper Limits have been set for eight vitamins and minerals, with guidance issued for 22.

As defined by the EFSA, the definition of a tolerable intake refers to what can be physiologically tolerated by the human body, and is a scientific judgement based on the probability of an adverse effect occurring at a specified level of exposure.2

The UL is not a recommended level of intake, but are instead an estimate of the highest level of intake that carries no appreciable risk of adverse health effects.

Diet and supplements

It can be tricky to know exactly what to eat and what to supplement to comply with the different nutrient and energy criteria set. This article is a useful resource to understand how a balanced diet can be achieved, while in another article nutritionist Rob Hobson pinpoints dietary improvements that we could make as a nation.

It is also possible to track and analyse your own diet using a dietary tracker tool, which provides a report on calorie, macronutrient and micronutrient intake.

What's more, Healthspan supplements are formulated to take into account the fact that individuals may use more than one product, so we take care to consider the dose used in our formulations to help avoid reaching the UL.

However, if you are taking multiple supplements it is always important to check that you are not exceeding the UL as set by EFSA. This can be done by following the reference links provided in the body of this article or by clicking the references link below.


1European Food Safety Authority (2017). Overview on Dietary Reference Values for the EU population as derived by the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Summary of Dietary Reference Values
2 European Food Safety Authority (2006). Tolerable upper intake levels for vitamins and minerals. Scientific Committee on Food and Scientific Panel on Dietetic Products, Nutrition and Allergies


There are currently no comments, be the first to comment.

Leave a comment!

You need to login to add a comment.