Relative to the food we eat, the size of individual nutrients are actually incredibly small. As a result, we need to use units other than grammes (g) to describe them. Here’s what the common units for nutrients are:
Grammes (G)- often used to describe nutritional powders. Most teaspoons of powder weigh approximately 5g.
Milligrams (Mg)- 1000mg is equal to 1g
Micrograms (Mcg or μg)- 1000μg is equal to 1mg
International Units (IU)- Slightly more complex than milligrams (mg) and micrograms (μg), International Units measure differently from nutrient to nutrient. The most common nutrients that are likely to be measured in IU are vitamins D, E and A.
Vitamin D: 1 IU is the equivalent of 0.025 μg of D2 or D3
Vitamin A: 1 IU is the equivalent of 0.3 mcg retinol
Beta-carotene (provitamin A): 1 IU is the equivalent of 0.6 μg of beta carotene
Vitamin E: 1 IU is the equivalent of 0.67 mg d-alpha-tocopherol