What is the Recommended Dietary Intake of Vitamin A?
The Recommended Dietary Intake (RDI) simply means what the body requires each day to maintain a healthy life.
Vitamin A is essential for reproduction, growth, immunity, vision and development of the embryo and the foetus.
Vitamin A is only found in animal foods, notably in dairy foods, seafood and liver. Plant foods, like carrots, pumpkin, squash and spinach are noted for their carotenoid content. Carotenoids, like Betacarotene are converted in the body into Vitamin A when the body requires it. Due to the vitamin A content in foods being sensitive to heat it is not recommended to over cook these foods as they will lose their nutrient content.
The main food sources according to www.choice.com.au : It's chiefly found in liver and cod liver oil; some is also in oily fish, eggs, milk, butter and cream. The body can also easily convert it from the beta carotene in dark green vegetables and orange and red fruits and vegetables. It's usually added to margarines.
Up to 25,000 IU (7,500 mcg) of vitamin A per day is considered safe for most adults. However, women who are or could become pregnant should take less than 10,000 IU (3,000 mcg) per day of vitamin A to avoid the risk of birth defects. All supplements containing vitamin A will carry the warning that more than 2,500 IU may cause birth defects.
The Teratology Society in the United States recommends a daily intake of 8000 IU for pregnant women, or a supplement for pregnant women whose dietary intake means they are receiving less than 2,200 IU daily, because deficiencies are also associated with birth defects and poor pregnancy outcomes.
Recommended Daily Intake of Vitamin A
Recommendations by life stage and gender according to NHMRC
Infants
0-6 months 250 mcg/day
7-12 months 430 mcg/day
Children & adolescents
1-3 yr 300 mcg/day
4-8 yr 400 mcg/day
Boys
9-13 yr 600 mcg/day
14-18 yr 900 mcg/day
Girls
9-13 yr 600 mcg/day
14-18 yr 700 mcg/day
Men
19-30 yr 900 mcg/day
31-50 yr 900 mcg/day
51->70 yr 900 mcg/day
Women
19-30 yr 700 mcg/day
31-50 yr 700 mcg/day
51-70 yr 700 mcg/day
>70 yr 700 mcg/day
Pregnancy
14-18 yr 700 mcg/day
19-30 yr 800 mcg/day
19-50 yr 800 mcg/day
Lactation
14-18 yr 1,100 mcg/day
19-30 yr 1,100 mcg/day
19-50 yr 1,100 mcg/day
These amounts are also in line with the most recent decision of the FAO Food and Agricultural Organization of the United Nations, (FAO Food and Agricultural Organization of the United Nations: WHO World Health Organization of the United Nations 2001).