Vitamin A is an essential vitamin which has two basic forms: retinoids (found in animal foods) and carotenoids (found in plant foods). The body is able to convert beta carotene to vitamin A. Vitamin A is required for vision, improving immune function, and skin health. It has also been shown to improve mortality among children suffering from measles. A deficiency in vitamin A can lead to blindness and increased rates of viral infection, however deficiency is only considered a problem in developing countries where it is a leading cause of blindness in children.
Vitamin A and mortality in children with measles:
The supplementation of Vitamin A in children with measles was documented to have an association with lower mortality rate in both malnourished and overall healthy children diagnosed with the disease. Vitamin A may reduce in morbidity and mortality by about 50% may also prevent eye damage and blindness. The World Health Organization recommends that all children diagnosed with measles throughout the world receive vitamin A supplementation regardless of which country they live.
Vitamin A and mortality in children: Randomized trials (43 trials total) of oral vitamin A supplements in children aged 6 months to 5 years (n=215,633) were analyzed to determine the effect of vitamin A on child mortality. All-cause mortality was reduced by 24% in 17 trials. Mortality associated with diarrhea was reduced by 28% in 7 trials. Reductions in occurrences of diarrhea, measles, and vision problems (night blindness and a medical condition in which the eye fails to produce tears) were reported among those taking vitamin A supplements. In 3 trials, risk of vomiting increased during the first 48 hours of supplementation. These findings are especially relevant to low and middle-income countries since most of the studies were conducted in Asia, Africa, and Latin America. (1)
Vitamin A was shown to have beneficial effects on morbidity and mortality rates among children suffering from measles in studies conducted in Africa. A study of children with measles (n=20) in California revealed that 50% suffered from Vitamin A deficiency. Therefore, vitamin A should be evaluated as part of treatment for measles in the US. (2)
A meta-analysis that included 12 controlled trials evaluated the effect of vitamin A and child mortality. Results indicate vitamin A taken by hospitalized children suffering from measles has a beneficial effect on mortality. Vitamin A also has a beneficial effect on overall mortality in healthy children. (3)
Vitamin A and iron deficiency:
According to researchers that conducted a systematic review of studies about the relationship of vitamin supplementation to anemia, vitamin A was found to improve blood indicators and the effectiveness of iron supplementation (4). Vitamin A has also been known to make iron supplements more effective (5).
Vitamin A and retinitis pigmentosa:
Researchers conducted a randomized, controlled, double-blind trial to determine whether vitamin A or vitamin E, alone or in combination, would stop or slow the progression of retinitis pigmentosa, an eye disease in which there is damage to the retina. A total of 601 patients aged 18-49 years old over where assigned to either 15,000 IU/d of vitamin A, 15,000 IU/d of vitamin A plus 400 IU/d of vitamin E, trace amounts of both vitamins, or 400 IU/d of vitamin E. Findings show that those receiving 15,000 IU/d of vitamin A had on average a slower rate of decline of retinal function than the two groups not receiving this dosage. However, 400 IU/d of vitamin E had a negative impact on the progression of retinitis pigmentosa. (5)
Vitamin A and immune response:
Vitamin A deficiency often occurs in the U.S. population which may exacerbate iron deficiency and reduce the immune response to infection. Retinol supplements have an upper limit recommendation of 3000 IU/day. Vitamin A supplements in particular have been shown to increase growth and birth weight in babies born to HIV infected pregnant women. It is important to avoid both deficiency and excess intake of vitamin A which may result in toxicity. (6)
Vitamin A and colon cancer:
Antioxidant vitamins A, C, and E were found to lower the recurrence rate of cancers of the colon. Individuals (n=255) with a history of colonic adenoma were randomized to receive treatment with either (1) vitamin A (30,000 IU per day), vitamin C (1 gram per day), and vitamin E (70 mg per day); (2) lactulose; or (3) placebo for an average of 18 months. At the end of the treatment period, adenoma recurrence had occurred in 5.7% of the antioxidant vitamin group compared to 14.7% in the lactulose group and 35.9% in the placebo group. (7)
Vitamin A and smoking:
The Beta-Carotene and Retinol Efficacy Trial (CARET), showed that among 18,314 men and women who smoked heavily or were exposed to asbestos, daily intake of 30 mg (100,000 IU) of beta-carotene and 25,000 IU vitamin A failed to decrease the risk of cancer or heart disease. The study was stopped early because it showed that beta-carotene/vitamin A takers who were heavy smokers, ex-smokers or asbestos workers were showing a 28% increased risk of lung cancer in smokers (versus placebo) and a 17% more likely chance of dying, mostly of lung cancer or heart disease. Results of a 6-year follow-up of study participants showed that compared to the placebo or no intervention group, participants who had taken the intervention had a 12% and 8% increase in relative risk of lung cancer and all-cause mortality among the intervention group, respectively. Researchers also found that after the intervention was stopped relative risk of cardiovascular disease mortality dropped and there was no difference in risk between the two groups. Finally, they found that women were more affected by the supplements with a larger relative risk of lung cancer mortality (1.33 versus 1.14; P = .36), cardiovascular disease mortality (1.44 versus 0.93; P = .03), and all-cause mortality (1.37 versus 0.98; P = .001) than males. (8)
Vitamin A recommendations:
For the prevention of cancer or cardiovascular disease, the U.S. Preventive Services Task Force (USPSTF) expressed that there is insufficient evidence to recommend for or against the use of vitamins A, C, or E supplements or multivitamins with folic acid or antioxidant combinations for the prevention of cancer or cardiovascular disease. The USPSTF also recommends against use of beta-carotene supplements, alone or in combination. (9)
Common Highest Vitamin A Containing Foods:
| Carrot juice, canned, 1 cup | 45133 IU |
| Pumpkin, canned, without salt, 1 cup | 38129 IU |
| Sweet potato, cooked, baked in skin, without salt, 1 potato | 28058 IU |
| Carrots, cooked, boiled, drained, without salt, 1 cup | 26571 IU |
| Carrots, frozen, cooked, boiled, drained, without salt, 1 cup | 24715 IU |
| Sweet potato, cooked, boiled, without skin, 1 potato | 24554 IU |
| Spinach, frozen, chopped or leaf, cooked, boiled, drained, without salt, 1 | 22916 IU |
| Turkey, whole, giblets, cooked, simmered, 1 cup | 22326 IU |
| Beef, variety meats and by-products, liver, cooked, pan-fried, 3 oz | 22175 IU |
| Spinach, canned, regular pack, drained solids, 1 cup | 20974 IU |
| Sweet potato, canned, vacuum pack, 1 cup | 20357 IU |
| Collards, frozen, chopped, cooked, boiled, drained, without salt, 1 cup | 19538 IU |
| Kale, frozen, cooked, boiled, drained, without salt, 1 cup | 19115 IU |
| Vegetables, mixed, canned, drained solids, 1 cup | 18991 IU |
| Spinach, cooked, boiled, drained, without salt, 1 cup | 18866 IU |
| Carrots, raw, 1 cup | 18377 IU |
| Sweet potato, canned, syrup pack, drained solids, 1 cup | 17971 IU |
| Kale, cooked, boiled, drained, without salt, 1 cup | 17707 IU |
| Turnip greens, frozen, cooked, boiled, drained, without salt, 1 cup | 17655 IU |
| Mustard greens, cooked, boiled, drained, without salt, 1 cup | 17318 IU |
| Carrots, canned, regular pack, drained solids, 1 cup | 16308 IU |
| Collards, cooked, boiled, drained, without salt, 1 cup | 14440 IU |
| Pumpkin, cooked, boiled, drained, without salt, 1 cup | 14100 IU |
| Pie, pumpkin, prepared from recipe, 1 piece | 12431 IU |
| Carrots, raw, 1 carrot | 12028 IU |
| Beet greens, cooked, boiled, drained, without salt 1 cup | 11022 IU |
| Turnip greens, cooked, boiled, drained, without salt, 1 cup | 10980 IU |
| Squash, winter, all varieties, cooked, baked, without salt, 1 cup | 10707 IU |
| Chicken, broilers or fryers, giblets, cooked, simmered, 1 cup | 8510 IU |
| Squash, winter, butternut, frozen, cooked, boiled, without salt, 1 cup | 8014 IU |
| Vegetables, mixed, frozen, cooked, boiled, drained, without salt, 1 cup | 7784 IU |
| Cabbage, chinese (pak-choi), cooked, boiled, drained, without salt,1 cup | 7223 IU |
| Dandelion greens, cooked, boiled, drained, without salt, 1 cup | 7179 IU |
| Sweet potato, cooked, candied, home-prepared, 1 piece | 6850 IU |
| Soup, chicken vegetable, chunky, canned, ready-to-serve,1 cup | 5990 IU |
| Soup, chunky vegetable, canned, ready-to-serve, 1 cup | 5878 IU |
| Melons, cantaloupe, raw, 1 cup | 5411 IU |
| Lettuce, butterhead (includes boston and bibb types), raw, 1 head | 5399 IU |
| Lettuce, cos or romaine, raw, 1 cup | 4878 IU |
| Peppers, sweet, red, raw, 1 cup | 4665 IU |
| Lettuce, green leaf, raw, 1 cup | 4147 IU |
| Apricots, canned, juice pack, with skin, solids and liquids, 1 cup | 4126 IU |
| Peppers, sweet, red, cooked, boiled, drained, without salt, 1 cup | 4000 IU |
| Tomato products, canned, paste, without salt added,1 cup | 3996 IU |
Adapted from: Nutritive Value of Foods, United States Department of Agriculture, Agricultural Research Service, Home and Garden Bulletin Number 72. May be accessed at:
https://www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/SR25/nutrlist/sr25w318.pdf and
http://www.nal.usda.gov/fnic/foodcomp/Data/HG72/hg72_2002.pdf
Assessment and Plan: Vitamin A
- Vitamin A supplements in children aged 6 months to 5 years reduced all-cause mortality by 24% in 17 trials evaluated by Mayo-Wilson E., et al. Mortality associated with diarrhea was found to be reduced by 28% in 7 trials. Vitamin A was also found to reduce occurrence of diarrhea, measles, and vision problems. These findings are especially important in countries such as Asia, Africa, and Latin America. (1)
- The supplementation of Vitamin A in children with measles was documented to have an association with lower mortality rate in both malnourished and overall healthy children diagnosed with the disease. Vitamin A may reduce in morbidity and mortality by about 50% may also prevent eye damage and blindness. The World Health Organization recommends that all children diagnosed with measles throughout the world receive vitamin A supplementation regardless of which country they live. See vitamin A for more information about this nutrient.
- For patients at risk of iron deficiency, vitamin A improves the effectiveness of iron supplementation. (4)
- In patients with retinitis pigmentosa, 15,000 international units per day of vitamin A had on average a slower rate of retinal function decline than two groups not receiving this dosage.
- Inadequate vitamin A intake may exacerbate iron deficiency and degrade immunity, but excess intake of vitamin A may result in toxicity. (6)
- The U.S. Preventive Services Task Force (USPSTF) expressed that insufficient evidence exists to recommend for or against the use of vitamins A, C, or E supplements or multivitamins with folic acid or antioxidant combinations for the prevention of cancer or cardiovascular disease (9). However, a study by Roncucci L et al found that antioxidant vitamins A, C, and E (30,000 IU per day, 1 gram per day, and 70 mg per day respectively) lowered the recurrence rate of cancers of the colon including a reduction in adenoma recurrence of 5.7% of the antioxidant vitamin group compared to 14.7% in a group taking lactulose and 35.9% in the placebo group. (7)
- Beta carotene is a pro-vitamin A and converts to vitamin A in the body. Vitamin A or beta carotene is best consumed in food sources since supplements may be harmful. See the section on beta-carotene for detailed information. Heavy smokers, ex-smokers or asbestos workers who took beta-carotene and vitamin A supplements showed a significant increase in the risk of lung cancer (8).
- For a breakdown of vitamin A containing foods see: Adapted from: Nutritive Value of Foods, United States Department of Agriculture, Agricultural Research Service, Home and Garden Bulletin Number 72. May be accessed at: https://www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/SR25/nutrlist/sr25w318.pdf and http://www.nal.usda.gov/fnic/foodcomp/Data/HG72/hg72_2002.pdf
- For a breakdown of beta-carotene containing foods see: Adapted from: Nutritive Value of Foods, United States Department of Agriculture, Agricultural Research Service, Home and Garden Bulletin Number 72. May be accessed at: http://www.nal.usda.gov/fnic/foodcomp/Data/HG72/hg72_2002.pdf or https://www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/SR25/nutrlist/sr25w321.pdf
References :
1.Mayo-Wilson E, Imdad A, Herzer K, Yakoob MY, Bhutta ZA. Vitamin A supplements for preventing mortality, illness, and blindness in children aged under 5: systematic review and meta-analysis. BMJ. 2011 Aug 25;343:d5094. http://www.ncbi.nlm.nih.gov/pubmed/21868478
2.Arrieta AC, Zaleska M, Stutman HR, Marks MI. Vitamin A levels in children with measles in Long Beach, California. J Pediatr. 1992 Jul;121(1):75-8. http://www.ncbi.nlm.nih.gov/pubmed/1625097
3.Fawzi WW, Chalmers TC, Herrera MG, Mosteller F. Vitamin A supplementation and child mortality. A meta-analysis. JAMA. 1993 Feb 17;269(7):898-903. http://www.ncbi.nlm.nih.gov/pubmed/8426449
4.Fishman SM, Christian P, West KP. The role of vitamins in the prevention and control of anaemia. Public Health Nutr. 2000 Jun;3(2):125-50. http://www.ncbi.nlm.nih.gov/pubmed/10948381
5.Berson, EL., Rosner, B., Sandberg, MA., Hayes, KC., Nicholson, BW., Weigel-DiFranco, C., Willett, W., A randomized trial of vitamin A and vitamin E supplementation for retinitis pigmentosa. Arch Ophthalmol. 1993 Jun;111(6):761-72. http://www.ncbi.nlm.nih.gov/pubmed/8512476
6.Hovdenak N, Haram K. Influence of mineral and vitamin supplements on pregnancy outcome. Eur J Obstet Gynecol Reprod Biol. 2012 Oct;164(2):127-32. http://www.ncbi.nlm.nih.gov/pubmed/22771225
7.Roncucci L, Di Donato P, Carati L, et al. Antioxidant vitamins or lactulose for the prevention of the recurrence of colorectal adenomas. Colorectal Cancer Study Group of the University of Modena and the Health Care District 16. Dis Colon Rectum. 1993 Mar;36(3):227-34. http://www.ncbi.nlm.nih.gov/pubmed/8449125
8.Goodman GE, et al. The Beta-Carotene and Retinol Efficacy Trial: incidence of lung cancer and cardiovascular disease mortality during 6-year follow-up after stopping beta-carotene and retinol supplements. J Natl Cancer Inst. 2004;96(23):1743-50. http://www.ncbi.nlm.nih.gov/pubmed/15572756
9.Routine Vitamin Supplementation to Prevent Cancer and Cardiovascular Disease, Topic Page. June 2003. U.S. Preventive Services Task Force. http://www.uspreventiveservicestaskforce.org/uspstf/uspsvita.htm
10.Nutritive Value of Foods, United States Department of Agriculture, Agricultural Research Service, Home and Garden Bulletin Number 72. May be accessed at: https://www.ars.usda.gov/SP2UserFiles/Place/12354500/Data/SR25/nutrlist/sr25w318.pdf or http://www.nal.usda.gov/fnic/foodcomp/Data/HG72/hg72_2002.pdf