Potentially confusing different terms are used when referring to the amount of a
particular nutrient (such as calcium or vitamin D) your body needs for good health
and when measuring the amount of a particular nutrient in a serving of food or in a
dietary supplement. The amount of a vitamin is often listed in International Units
(IU) that relate to the biological effects of the vitamin. For example, one IU is equal
to 0.3 micrograms (μg) of vitamin A (retinol), but for vitamin D, one IU is equal to
Dietary Reference Intakes (DRIs) are a family of nutrient reference values, including
the Estimated Average Requirement (EAR)s that are intended to serve as a guide for
good nutrition and to provide the basis for the development of nutrient guidelines.
The EAR is used for planning and assessing diets of populations; it also serves as
the basis for calculating the Recommended Dietary Allowances (RDA).
RDAs are the recommended daily intakes of a nutrient for healthy people and a value
intended to meet or exceed the requirement for 97.5% of the population. They tell
you, on average, how much of that nutrient you should be getting each day. RDAs
are developed by the Food and Nutrition Board of the Institute of Medicine of the
National Academies. Because RDAs vary by age, gender, and whether a woman is
pregnant or breastfeeding, there are many different RDAs for each nutrient.
Tolerable Upper Intake Level (UL) is the highest average daily intake that is likely
to pose no risk of adverse effects to almost all individuals in the general population.
As intake increases above the UL, the potential risk of adverse effects may increase.
Daily Values (DVs) describe how much (in percentage) of a nutrient a serving of the
food or supplement provides in the context of a total daily diet. DVs are established
by the FDA and are used on food and dietary supplement labels. For each nutrient,
unlike the RDAs, there is one DV for all people ages four years and older. Therefore,
DVs aren’t recommended intakes, but DVs often match or exceed the RDAs
for most people. DVs are presented on food and supplement labels as a percentage.
For example, the DV for calcium on a food label might say 20%. This means it has
200 mg (milligrams) of calcium in one serving because the DV for calcium is 1,000
mg/day. The FDA has a web page that lists the DVs for all nutrients.
The Recommended Dietary Allowances (RDA) is the best guide to how much of a
nutrient to consume for good health. Still, most people eating a varied plant-based
healthy diet do not need to be concerned about the precise content of vitamins and
other nutrients in the food they eat.
This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel