you have a medical condition or treatment that means you may not be able to safely take as much vitamin D as the general population Do not exceed the recommended dose (1 supplement per day containing 10 micrograms (µg) equivalent to 400 international units). This is a safe level of intake, designed to meet your nutritional needs. Taking more is not currently recommended.

and folic acid were reported as µg folic acid. New FDA guidelines require that folates/folic acid be reported in DietaryLet's say that I have a soft gel capsule that contains 500 IU of Vitamin A as retinol. To convert this to mcg, using the information above, I would multiply it by 0.3:

I think that people wonder why the International unit isn't in the lists featured in the mass and weight converter. The reason for this is that the conversion isn't as simple as one might think. Let's start this article by discussing what an International unit is. What is an International unit? In the United States, current guidelines suggest that consuming 400–800 International Units (IU), or 10–20 micrograms (mcg), of vitamin D should meet the needs of 97%–98% of all healthy people ( 14). These two units of measurement are often used interchangeably with vitamin D, as it is not typically measured in “mg” like most other vitamins and minerals. For instance, one review of 17 studies found that vitamin D deficiency was associated with a significantly higher risk of developing colorectal cancer ( 18). Some of these forms have greater bioavailability than others. Vitamin A has previously been reported in internationalas mg alpha-tocopherol rather than in IU. Vitamin E in food and dietary supplements can come from natural or synthetic Excessive intake of vitamin D can only occur by taking dietary supplements. But one would have to take some 40,000 IU (1000 mcg) per day for several months to cause vitamin D overdose. Endogenous production of vitamin D is stimulated when a cholesterol compound in the skin is exposed to UVB light, with subsequent hydroxylation and activation at the liver and kidney level. From 10000 to 25000 IU of vitamin D can be produced endogenously when exposed to one erythemal dose of UV radiation (leaves a slight pinkness in the skin 24 hours following exposure). Endogenous vitamin D remains in the blood longer than ingested vitamin D.[xvi] Traditionally, serum 25-hydroxyvitamin D (25(OH)D) levels above 20 ng/mL (50 nmol/L) were accepted as “normal.” Insufficiency was defined as 12-20 ng/mL (30-50 nmol/L), and deficiency was defined as a value lower than 12 ng/mL (30 nmol/L).[i] IUs if the sources of vitamin A are known. 1 µg RAE = 1 µg retinol and 1 µg RAE = 2 µg supplemental beta-carotene.

Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful. This applies to adults, including pregnant and breastfeeding women and the elderly, and children aged 11 to 17 years. Take the recommended dose of vitamin D daily to maintain your vitamin D levels, as described in point 1 above. Or continue to spend the same amount of time in the sun to maintain your value. Your value is between 60 - 80 ng/ml Generally speaking, very few foods are great sources of vitamin D. However, the following foods are exceptions ( 27, 28, 29, 30, 31, 32, 33): New FDA guidelines require that niacin be reported as Niacin Equivalents (NE). Dietary niacin can come in several forms, and The most common form of vitamin E is the “dl-alpha tocopherol” form. If you see this form, you just multiply the IU by 0.45. For example:You may choose not to take a vitamin D supplement during these months. People at risk of vitamin D deficiency is the symbol for the metric measurement microgram, which is one thousandth of a milligram or one millionth of a gram. The letter µ is a greek letter, which means “small”, though often it “ug” or “mcg” (microgram) are used in its place due to typographical unavailability. Source: Benskin, Linda L. “A Basic Review of the Preliminary Evidence That COVID-19 Risk and Severity Is Increased in Vitamin D Deficiency.” Frontiers in public health vol. 8 513. 10 Sep. 2020, doi:10.3389/fpubh.2020.00513 This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). There are numerous recommendations which make taking vitamin D unnecessarily complicated. But if you follow the above dosage and have your 25(OH)D tested after 3 months, you'll see how easy it can be to get your vitamin D levels into the optimal range. What’s a DFE you might ask? It’s a “dietary folate equivalent.” This is a unit of measure that’s been developed to better equate the biological effects of the folate found in food compared to the synthetic sources of folate such as folic acid and methylfolate. Synthetic sources are more potent at increasing the folate levels in your body compared to food sources. So the amount of DFE provided by these sources is higher.