Dr. Laurell Matthews earned a bachelor’s degree in biochemistry and a doctorate in naturopathic medicine from Bastyr University.
With the Food and Drug Administration’s (FDA) release of new rules for nutrition and supplement facts panels, many nutrient measurement units have been revised. These changes are now in effect, and you will begin to see them appearing on labels. It is important to understand how to convert these units of measure. We have prepared this guide to help you and your clients understand how this new labeling compares to what you have seen in the past.
Vitamin D used to be shown on the label in International Units (IU), but now it is listed in micrograms (mcg).
- Unit conversion: 1 mcg = 40 IU
- Calculation: IU*0.025 = mcg
To compare how a new product listing micrograms of Vitamin D would have been labeled in IUs:
- Calculation: mcg*40 = IU
Product example: if a label previously listed 1,000 IU of Vitamin D, it will now read 25 mcg.
Vitamin A is listed on the new nutrition and supplement labels in mcg of Retinol Activity Equivalents (RAE). Formerly Vitamin A was listed in IUs.
The conversion from IUs to mcg RAE considers whether the Vitamin A is in the form of a dietary supplement or naturally present in a food, but here we are only considering dietary supplement forms.
You can determine the Vitamin A mcg RAE value by converting from IUs using this formula:
Vitamin A in a dietary supplement (ex. retinyl palmitate or beta-carotene)
- Unit conversion: 1 mcg RAE = 0.3 IU
- Calculation: IU*0.3 = mcg RAE
Example: 10,000 IU of Vitamin A in a dietary supplement will now be listed on the label as 3,000 mcg RAE.
Vitamin E’s label unit has changed from IU to mg of alpha-tocopherol. The conversion factor depends on whether the source is natural or synthetic. At Energique®, we only use the natural form of Vitamin E, so only that conversion is given here. Other tocopherols, such as gamma-tocopherol, are not listed as Vitamin E, but as mg of gamma-tocopherols or mixed tocopherols.
Natural Vitamin E (d-alpha tocopherol)
- Unit conversion: 1 mg alpha-tocopherol = 1.49 IU
- Calculation: IU*0.67 = mg alpha-tocopherol
For example, a product that used to contain 400 IU of Vitamin E as d-alpha tocopherol will now be listed as 268 mg.
Niacin’s label unit has changed from mg of Niacin to mg of Niacin Equivalents (NE). This allows us to take into account that our bodies convert some of the amino acid tryptophan into niacin, but otherwise doesn’t affect how niacin is denoted other than the additional terminology of “Niacin Equivalents.”
From Niacin (including niacinamide and other versions of niacin)
- Unit conversion: 1 mg Niacin Equivalent = 1 mg Niacin
- Calculation: None needed.
From the amino acid tryptophan
- Unit conversion: 1 mg Niacin Equivalent = 60 mg tryptophan
- Calculation: tryptophan/60 = mg Niacin Equivalent
Folate has changed from mcg to mcg DFE (Dietary Folate Equivalents). The conversion factor depends on the source of folate, since different forms of folate vary in their bioavailability.
Natural source: in food
- Unit conversion: 1 mcg DFE = 1 mcg Folate in food
- Calculation: None needed.
Synthetic source in a dietary supplement (including folic acid and (6S)-5-methyltetrahydrofolic acid)
- Unit conversion: 1 mcg DFE = 1.7 mcg Folic Acid
- Calculation: Folic Acid x 1.7 = mcg Folate DFE
Product example: 800 mg of (6S)-5-Methyltetrahydrofolic acid will now be labeled as 1,360 mcg DFE.
Any homeopathic claims are based on traditional homeopathic practice, not accepted medical evidence. Not FDA evaluated.
These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.