???????????????? ???????????????????????????????????????????? ???????????????????????? ???????? ???????????????? ???????? ???????????????????????????? ???????????? ???????????????????????? ???????????????? ???????? ???????????????????????????????????????????????? ????????????????????. ???????????? ???????????????? ???????????????????? ???????? ???????????????????????????? ???? ???????????????????????? ???????????????????????????? ???????????????? ???????? ???????????????????????? ????????????????????????????????????????????????.
Vitamin A is a fat soluble vitamin with a half-life of 75 days in the body.
In dietary supplements, Vitamin A often comes in the form of: ???????????????????????????? ???????????????????????????? ???????? ???????????????????????????? ???????????????????????????????????? which are ????????????-???????????????????????? and also exist in animal products; and ???????????????? ???????????????????????????????? ???????????????????? ???????? ???? ???????????????????????????????????????? ???? and exists in plant based foods. you can also get a mixture of both in supplement form.
???????????????? ???????????????????????????????? can be obtained from foods rich in carotenoids which are often colorful fruits and vegetables.
More about vitamin A consumption
Consumption of five servings of fruits and vegetables per day could provide 5.2 to 6 mg/day of provitamin A carotenoids (Lachance, 1997), which would contribute approximately 50 to 65 percent of the men’s RDA for vitamin A.
Role of Vitamin A in the body
Vision, Bone Growth, Reproduction, Cell Division And Differentiation, Immune System Regulation, Healing Of The Respiratory Tract And Its Development, And Gene Transcription.

Vitamin A Deficiency
???????????????????????????????????????? is rare however 35% of Canadians over 19 years of age have inadequate intakes. Some symptoms include: ???????????? ????????????????, ???????????????? ???????????? ????????????????; ???????????????????????????????????????????? ???????????????? ????????????????????, ???????????????????????????????????? ???????????????????????????????????????? ???????? ???????????????????????????????????????? (???????????????????????????????????????? ???????????????? ???????? ???????????????????????? ???????????????? ????????????????), ???????????????????? ????????????????????????????????????, ???????????????????????? ????????????????????????????????????????????, ???????????????????????????????? ???????????????????????????? ???????? ???????????????????????????? ????????????????????, ???????????????????????????????????????? ???????????????????????????????????????????????????????? ???????? ???????????? ????????????????, ???????????? ????????????????. A number of factors can influence the requirement for vitamin A, including iron status, the presence and ???????????????????????????????? ???????? ???????????????????????????????????? ???????????? ????????????????????????????????????, ???????????? ???????????????????? ???????? ???????????????????????????? ????????????, ???????????????????????????? ???????????????????????? ????????????????????????????????????????????????, ???????????? ???????????? ???????????????????????????????????? ???????????????????????????? ???????????? ???????????????????????????????????? ???????????????????????????? ???? ???????????? ???????????????????????????????????????? ???? ????????????????????????????????????????????. ???????????? ???????????????????????????? ???????????????????????????????????? ???????? ???????????????????????????? ???? ???????? ???????????????????????????????????? ???????????????? ????????????????????????????????????, ???????????? ???????????????????????????????????????? ???????????????? ???????????????????? (???????????????????????????? ???????? ????????., ????????????????; ???????????????????????????????????????? ???????? ????????., ????????????????). ???????????? ???????????????????? ????????????????????????????, ???????????????? ???????????????????????????????????? ???????????????????????????????????????????? ???????????? ???????????????????????? ????????????????????????????????????, ???????????? ???????????????????????????????????????????? ???????????? ???????????????????????????? ???? ???????????? ???????? ???????????????????????????? ???????????????? ???????????? ???????????????????????????????????????????????? ???????????? ???????? ???????????????? ????????????????????????, ???????????????????? ???????????? ???????????????????? ???????? ???????????????????????????????????? ???????????????????????????? ????????????????????????????????????????????.
Vitamin A Dosage

Recommended dietary allowance for vitamin A

Lab
Serum retinol
Toxic Doses
10,000 units a day daily can cause liver toxicity, birth defects, nausea, vomiting, altered mental status, abdominal pain, blurred vision, headache, muscle pain, weakness, increase in fracture risk, and can cause toxicity in alcoholics. Toxicity does not have to present symptoms.
Population at risk
Individuals from developing countries, people with crohn’s disease, celiac disease, pancreatic diseases.