Conversions

Calories (kilocalories) to kilojoules

To convert Calories to kilojoules, multiply Calories by 4.184.

1 Calorie = 4.184 kilojoules (kJ)

Vitamin A

The conversion factor depends on its source, animal or plant. 

1 Retinol Equivalent (RE)  = 1 mcg Retinol

= 6 mcg beta carotene

= 12 mcg other provitamin A carotenoids

= 3.33 IU from animal foods (Retinol)

= 5 IU from mixed foods 

= 10 IU from plant foods (carotenoids)

1 Retinol Activity Equivalent (RAE) = 1 mcg Retinol

= 12 mcg beta carotene

= 24 mcg other provitamin A carotenoids

= RE, if RE = retinol = RE x 0.5, if RE = carotenoids

Vitamin D

To convert IU of vitamin D to mcg, divide the IU by 40.

40 IU of vitamin D       = 1 mcg of cholecalciferol (vitamin D3)

= 1 mcg of ergocalciferol  (vitamin D2)

Vitamin E

The DRI standard for Vitamin E is measured in mg of alpha-tocopherol. Nutrition Facts labeling panels display Vitamin E in IU units. The following shows the mathematical conversion between these two measures of Vitamin E:

1 IU Vitamin E       = 0.67 mg RRR-alpha-tocopherol (natural)

= 0.9 mg all rac alpha-tocopherol (synthetic)

Vitamin E mg and Vitamin E a-TE are kept in the program so that they can be recalled for past saved diets, but they are rarely used for current Vitamin E analysis.

Niacin & Niacin Equivalents

Niacin equivalents = niacin (mg) + [tryptophan (mg) / 60] 

Folate

1 mcg DFE (Dietary Folate  Equivalent) = mcg of food folate  + (1.7 x mcg synthetic folic acid)