Prevent Chronic Infections with Vitamin A
For supplemental vitamin A, only a minimal dosage should be taken regularly.
Vitamin A deficiency is associated with recurrent infections[1]; with severe cases of measles, pneumonia, and diarrhea[2]; all cause mortality[3]; as well as with a major reduction in deaths from malaria[4]; not to mention night blindness.
"Vitamin A deficiency impairs innate immunity by impeding normal regeneration of mucosal barriers damaged by infection, and by diminishing the function of neutrophils, macrophages, and natural killer cells. Vitamin A is also required for adaptive immunity and plays a role in the development of T both-helper (Th) cells and B-cells. In particular, vitamin A deficiency diminishes antibody-mediated responses directed by Th2 cells, although some aspects of Th1-mediated immunity are also diminished. These changes in mucosal epithelial regeneration and immune function presumably account for the increased mortality seen in vitamin A-deficient infants, young children, and pregnant women in many areas of the world today."
..
"Vitamin A is essential in maintaining the integrity of the epithelial barrier, the first line of defense against many infections."[5]
Eat Plant-Based Vitamin A Foods
Vitamin A & Innate Immunity
When it comes to your innate immunity, research shows that increasing your blood levels of animal sources of vitamin A, or retinol, improves some immune functions while depressing others. Thus, taking chronically large dosages of vitamin A cannot be clearly supported, nor recommended.
Vitamin A is part of Mucosa-Associated Lymphoid Tissue
The above quotation from scientific research indicates that vitamin A establishes and maintains a strong presence at the mucosal boundary of all Mucosa-Associated Lymphoid Tissue (MALT).
MALT can be divided into the following sub-systems:
- GALT (gut-associated lymphoid tissue [i.e., intestines])
- BALT (bronchus-associated lymphoid tissue [i.e., lungs])
- NALT (nasal-associated lymphoid tissue [i.e., nose])
- CALT (conjunctival-associated lymphoid tissue [i.e., eyes])
Animal forms of vitamin A, retinol, is a chronic liver toxin that should be treated with respect due to its long-term toxic effects upon the liver. Reported human deaths from getting too much vitamin A first came from early arctic explorers who died after having eaten Polar bear liver. Vitamin A supplementation should be viewed literally as a ticking time bomb. Unused supplemented retinol gradually accumulates in the liver. At some point, excessive vitamin A supplementation over a lifetime theoretically can result in liver failure. A liver transplant was required in as little as six months, when one elderly woman decided to take 400,000 IU of vitamin A daily.
The toxic side of vitamin A is NOT nearly as bad as some people make it out to be. There is some indication that you liver only retains vitamin A for 2 years. And, that your body uses vitamin A stored in the liver as needed. Hence, you really only need to avoid chronically taking extremely large dosages of the animal form of vitamin A. After two years, everyone probably starts off with a clean slate.
Currently, the recommended daily allowance is 5,000 IU a day for adults. This figure is based upon of all things preventing night blindness. The Natural Health Perspective actually recommends taking less than this daily dosage, or 8,000 to 10,000 IU of vitamin A twice a week, which has been calculated, to be enough to prevent chronic infections even while eating a horrible diet. This dosage should be high enough to put your serum blood levels into the mid to high range of what is generally considered normal. Everyone should set up a recurrent appointment in his or her computerized calendar in order to remind them when to supplement with vitamin A.
The Secret of Vitamin A
Therapeutic dosages at the onset of illness reveals the secret power of Vitamin A to fight infectious diseases.
Then in the remote event that you should ever come down with a major communicable disease, high fever, or internal infection, a one time therapeutic dosage of 50,000 IU of vitamin A three times a day for two or three days in a row is recommended. Published research shows that taking 200,000 IU daily for two days in a row is effective against severe measles in children in Africa[6], but that dosage is more of a brutal conventional medicine approach. Taking 50,000 IU three times a day is more gentler, as it gives your body more time to adjust to a sudden increase in vitamin A. You should be able to feel vitamin A working almost immediately. This therapeutic routine also offers some protection against forced vaccinations, if the final dosage is timed to be taken on the day of your vaccination. Of course, recommended dosages would vary by body weight. For children under twelve years of age, I would go with half of this therapeutic dosage, or 25,000 IU three times a day, for three days.
Dietary Sources of Vitamin A
Animal Sources of Vitamin A
Eating large amounts of liver accordingly cannot be recommended due to the animal vitamin A content of liver. If you do insist upon eating a lot of liver, than you accordingly must cut back on your vitamin A supplementation, as well as periodically monitor your blood levels with an appropriate vitamin A blood test.
Plant-Based Sources of Vitamin A
Thus, the safest approach to vitamin A is to get the majority of it from plant-based sources of pro-vitamin-A carotenoids (alpha-carotene, beta-carotene, gamma-carotene; and the xanthophyll beta-cryptoxanthin) that should be regularly a part of a healthy whole food diet. That way the intelligence of your body will convert pro-vitamin-A to retinol as it sees fit.
Furthermore, excess vitamin A supplementation during pregnancy can cause birth defects.
Please read our Medical Advice Disclaimer.
Please read our Nutritional Supplements Disclaimer.
References:
- Decreased vitamin A levels in common variable immunodeficiency: vitamin A supplementation in vivo enhances immunoglobulin production and downregulates inflammatory responses.
Aukrust P, Müller F, Ueland T,...
Eur J Clin Invest. 2000 Mar;30(3):252-9.
PMID: 10692003 - Vitamin A levels and immunity in humans.
Jason J, Archibald LK, Nwanyanwu OC, ...
Clin Diagn Lab Immunol. 2002 May;9(3):616-21.
PMID: 11986269 - Reduced mortality among children in southern India receiving a small weekly dose of vitamin A.
Rahmathullah L, Underwood BA, Thulasiraj RD, ...
N Engl J Med. 1990 Oct 4;323(14):929-35.
PMID: 2205798 - Major reduction of malaria morbidity with combined vitamin A and zinc supplementation in young children in Burkina Faso: a randomized double blind trial.
Zeba AN, Sorgho H, Rouamba N, ...
Nutr J. 2008 Jan 31;7:7.
PMID: 18237394 - Vitamin A, infection, and immune function.
Stephensen CB.
Annu Rev Nutr. 2001;21:167-92. Review.
PMID: 11375434 - "A deficiency is a recognized risk factor for severe measles. ... When stratified by dose, 200 000 IU of vitamin A given for 2 days was associated with a reduction in overall mortality ... and pneumonia-specific mortality ... in hospitalized children in areas with high case fatality. Greater reduction in mortality was observed in children under the age of 2 years ... On the other hand, a single dose of 200 000 IU of vitamin A was not associated with reduced mortality."
Vitamin A for the treatment of children with measles--a systematic review.
D'Souza RM, D'Souza R.
J Trop Pediatr. 2002 Dec;48(6):323-7. Review.
PMID: 12521271
