Vitamin A is an essential nutrient in our body.
It is a fat-soluble vitamin that found in animal products as preformed vitamin A (retinol) and in fruit and vegetables as the provitamin A, beta-carotene.
- It is necessary for healthy vision, the immune system and reproduction.
- Vitamin A also helps the heart, lungs, kidneys, and other organs work properly.
- Vitamin A required for regulating the growth and specialization of almost all cells in the human body.
- It takes part in embryonic development: organ formation during fetal development, normal immune functions, and eye development and vision.
Deficiency symptoms
Deficiency of vitamin A is associated with increased susceptibility to night blindness, infections, thyroid and skin disorders.
New RDA (Recommended Dietary Allowances) regulations
Under the new regulations, FDA’s new labelling regulations for foods and dietary supplements vitamin A will be listed on product labels only in μg RAE (retinol activity equivalents) and not IUs.
The recommended dietary allowance (RDA) is 700 micrograms of retinol activity equivalents (μg RAE)/day for women and 900 μg RAE/day for men.
| Age | Male | Female | Pregnancy | Lactation |
|---|---|---|---|---|
| 0–6 months* | 400 mcg RAE | 400 mcg RAE | ||
| 7–12 months* | 500 mcg RAE | 500 mcg RAE | ||
| 1–3 years | 300 mcg RAE | 300 mcg RAE | ||
| 4–8 years | 400 mcg RAE | 400 mcg RAE | ||
| 9–13 years | 600 mcg RAE | 600 mcg RAE | ||
| 14–18 years | 900 mcg RAE | 700 mcg RAE | 750 mcg RAE | 1,200 mcg RAE |
| 19–50 years | 900 mcg RAE | 700 mcg RAE | 770 mcg RAE | 1,300 mcg RAE |
| 51+ years | 900 mcg RAE | 700 mcg RAE |
* Adequate Intake (AI), equivalent to the mean intake of vitamin A in healthy, breastfed infants.
Food Sources
Animal-based food sources include dairy products, liver, and fish liver oils.
Rich sources of provitamin A carotenoids include orange and green vegetables, such as sweet potato and spinach.
When not to use the supplement? Contraindications:
pregnancy
Although it is needed to have sufficient vitamin A intake for healthy fetal development, excess of preformed vitamin A in a supplement form (such as retinol, animal-based vitamin) is not recommended.
If you check the levels of vitamin A on your prenatal multivitamins, you will find that it is usually driven from beta carotene (plant-based source) and will be in a low dosage.
The tolerable upper intake level for vitamin A in adults is set at 3,000 μg RAE/day (but it does not apply to vitamin A derived from carotenoids).
References-
- National Institutes of Health. 2019. Vitamin A Fact Sheet for Health Professionals. [ONLINE] Available at https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/.
- Oregon State University. 2019. Vitamin A. [ONLINE] Available at https://lpi.oregonstate.edu/mic/vitamins/vitamin-A.
* Adequate Intake (AI), equivalent to the mean intake of vitamin A in healthy, breastfed infants.
References-
- National Institutes of Health. 2019. Vitamin A Fact Sheet for Health Professionals. [ONLINE] Available at https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/.
- Oregon State University. 2019. Vitamin A. [ONLINE] Available at https://lpi.oregonstate.edu/mic/vitamins/vitamin-A.