Daily Vitamin A Requirement
Pure vitamin A is found exclusively in animal products. However, since the body can convert approximately 50 carotenoids found in plant-based foods into vitamin A (= provitamin A), the intake recommendations are given as retinol equivalents (RE) 1. The equivalents are used to standardize the daily requirement quantity, taking into account the conversion rates of different carotenoids to retinol (vitamin A). For example, the body needs 12 μg of beta-carotene to produce 1 μg of retinol, which corresponds to an RE ratio of 12:1. A conversion table for retinol equivalents can be found here.
For a table of vitamin A-rich foods, click here.
Vitamin A Daily Requirement for the United States
The following values have been issued as daily vitamin A intake recommendations for the United States by the NIH 2:
Gender and Age Group | Amount in μg RE |
---|---|
Men | |
≥ 19 years | 900 |
Women | |
≥ 19 years | 700 |
Pregnant ≥ 19 years | 770 |
Breastfeeding ≥ 19 years | 1,300 |
Children / Adolescents | |
0 to 6 months | 400* |
7 to 12 months | 500* |
1 to 3 years | 300 |
4 to 8 years | 400 |
9 to 13 years | 600 |
Boys 14 to 18 years | 900 |
Girls 14 to 18 years | 700 |
Pregnant, 14 to 18 years | 750 |
Breastfeeding, 14 to 18 years | 1,200 |
*Equivalent to the mean intake of vitamin A in healthy, breastfed infants, the Adequate Intake (AI) is determined.
1 mg retinol equivalent = 6 mg all-trans-β-carotene = 12 mg other provitamin A carotenoids = 1 mg retinol = 1.15 mg all-trans-retinyl acetate = 1.83 mg all-trans-retinyl palmitate; 1 IU (International Units are now only used in the pharmaceutical field) = 0.3 µg retinol
According to scientific findings, the daily requirement may be increased in individuals with hyperthyroidism, fever, infections, cold, and excessive exposure to sunlight 3. Those who consume alcohol heavily or have kidney diseases should also increase their vitamin A intake.
Covering the Requirement with a Vegan Diet
The vitamin A requirement can be met with a vegan diet 4. It is advisable to consume fruits and vegetables with deep yellow, orange, and red colors. Foods rich in vitamin A (retinol equivalents) can be found here.