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Immune Boost

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  • Boost Innate and Cellular  Immune Function
  • Activate antibody production
  • Protect the epithelium and mucous membranes
  • Regulate pro and anti inflammatory cells


IMMUNE BOOST Mega Vitamin A is a therapeutic high dose of Retinol acetate, which is a natural, water-based, form of vitamin A, plus Chelated Zinc and Selenium. The combination of the ingredient in Mega Vitamin A have been shown to boost innate cellular immunity and thymus activity, activate antibody production, protect the epithelium and mucous membranes of airways and intestines, and regulate pro-inflammatory and anti-inflammatory cells of the body. Mega doses of Vitamin A have been shown to safely and effectively boost immune function and reduce the risk of from viral pneumonia by 81 percent in children.  

Vitamin A is the Key to Boosting Your Cellular Immunity and Stopping Viruses

Vitamin A Boosts Barrier Defenses

The epithelium lines all outer surfaces and most inner surfaces of the body. It functions as the front-line of defense against the invasion of viruses and other pathogens. Vitamin A is essential for the maintenance of normal protective epithelial tissues throughout the body, including the lining of the lungs and the intestines. This is the first barrier of defense in preventing viruses from penetrating into the body. 

Vitamin A Protects the Epithelium and Mucous Membranes 

Vitamin A promotes mucin secretion in the epithelium, which provides a physical barrier and slows viruses down so that the Cellular Immune System can find and kill them.  Vitamin A deficiency leads to epithelial keratinization, or drying of the epithelial lining and a significantly depressed immune function. When Vitamin A is deficient it reduces the resistance of the lung tissues to invading viruses and it is no longer able to exert its mechanical barrier function, which can lead to respiratory tract infections, severe inflammation and pneumonia.

Vitamin A Boosts Thymus & Cell Mediated Immunity

Vitamin A also plays essential roles in the regulation, differentiation, maturity, and immunological function of all of crucial anti-viral cells of the Innate Cellular Immune System, including the Thymus. Vitamin A supports the Thymus, while deficiency is known cause atrophy of the Thymus.  Innate immune cells are comprised of Macrophages and Neutrophils, which initiate immediate responses to pathogen invasion through phagocytosis (virus digestion) and activation of Cytotoxic T-Cells and Natural Killer T-Cells, which kill viruses by the release of cytotoxic chemicals. 

Vitamin A Boosts Antibody Production

Antibodies represent a specific class of immunoglobulins. Vitamin A can boost the serum levels of Immunoglobulins and thereby enhance antibody production. Vitamin A deficiency leads to a defect in Antibody-dependent immune responses.

Vitamin A is a Powerful Regulator of Inflammation

Vitamin A is also essential for the regulation of tissue inflammation and tissue repair that occurs during a viral infection. Vitamin A promotes the development and differentiation of Monocytes and Macrophages in the lungs and the intestines. Macrophages include M1 Macrophages that secrete proinflammatory cytokines and M2 Macrophages that produce anti-inflammatory factors. 

Role of Vitamin A in the Immune System: J Clin Med. 2018 Sep; 7(9): 258; 

Retinoic Acid as a Modulator of T-Cell Immunity: Nutrients. 2016 Jun; 8(6): 349;

Malnutrition and Infection: Complex Mechanisms and Global Impact: PLoS Med. 2007 May; 4(5): e115. Published online 2007 May 1. doi: 10.1371/journal.pmed.0040115

How to Boost Your Immune System with Vitamin A

The most effective way to boost your immune system and avoid the most serious consequences of Viral assaults is a 2-day megadose of Vitamin A. This is dose of Vitamin A has been recommended and used by the World Health Organization for years in millions of children worldwide. It has reduced the death rate from viral pneumonia caused by Measles by 77% in the most seriously ill hospitalized infants and children. SARS-CoV-2 is causing a similar acute respiratory syndrome. Vitamin A can be taken safely to boost your immune system. Vitamin A is not a drug and not a treatment for any disease. It is nature’s key nutrient to boost your immune defense against invading organisms and cellular mutations. 

Taking 200,000 IU of Vitamin A daily for two consecutive days has been shown to be associated with a 82% reduction in the risk of death from the overwhelming effects of the measles virus in children under the age of two years (RR 0.18; 95% CI 0.03 to 0.61) and a 77% reduction in the specific risk of  mortality (RR=0.23; 95% CI 0.02 to 1.05) due to pneumonia. Vitamin A’s immune enhancing properties may provide similar immune enhancement and protection in adults against other viruses, like Coronavirus, that also cause severe lower respiratory tract inflammation.

Clinical Studies on patients taking Vitamin A for viral pneumonia have shown the patients taking the 2-day Therapeutic dose of  Vitamin A have much shorter hospital stay by almost five days compared to the placebo group (WMD -4.72, 95% CI -7.22 to 2.21). Additional research found that the group taking the 2-day Therapeutic dose of  Vitamin A was found to be 5 times more likely to have a complete recovery than the placebo group. (RR 1.54, 95% CI (1.04 to 1.88).

SourceVitamin A for treating measles in children. Cochrane Database Syst Rev. 2005 Oct 19;(4):CD001479. American Academy of Pediatrics

Dosage Schedule Recommended by the American Academy of Pediatrics and CDC

  • Infants aged <6 months: 50,000iu total per day (1-50,000iu capsule once daily for 2 days only)
  • Infants ages 6–11 months: 100,000iu total per day (2-50,000iu capsules once daily for 2 days only)
  • Children aged ≥12 months 200,000iu total per day (4-50,000iu capsules once daily for 2 days only)
  • Adults: 200,000iu total per day (4-50,000iu capsules once daily for 2 days only)
  • Pregnant women should NOT take more than 5,000 IU of Vitamin A per day

An additional (third) age-specific dose of vitamin A should be given 2–4 weeks later to children with clinical signs and symptoms of vitamin A deficiency. (Source: CDC, updated 12/13/13)

    How Much Vitamin A is Too Much? Can it be Toxic?

    The acute toxic dose of vitamin A is 25,000 IU/kg (approx. 1.5 Million IU/125 lbs or 2.0 Million IU/175 lbs body weight), and the chronic toxic dose is 4000 IU/kg (200,000 – 315,000 IU) every day for 6-15 months.


    Zinc is essential to the activation of Vitamin A and therefore to the Immune System .Zinc is a component of Retinol Binding Protein, a protein necessary for transporting Vitamin A in the blood. Zinc is also required for the enzyme that converts Vitamin A (Retinol) into Retinal and Retinoic Acid, the most active form of Vitamin A. Zinc is also the major cofactor in the production of Superoxide Dismutase, which may be the key antioxidant needed to stop the inflammatory cytokine storm seen in severe cases of COVID-19.*

    Zinc is a cofactor to more than 300 enzymes. Additionally, it is essential for membrane integrity, DNA synthesis, and cell proliferation, and thus is needed for all highly proliferating cells, especially the immune cells. Zinc has been shown to play an important role in the regulation of the immune response, preventing age related Thymus dysfunction, T-Lymphocyte proliferation and T cell function, including anti-viral killing. Zinc Blood levels above 70mcg/dl in elderly patients has been shown to reduce the incidence of pneumonia by 48%, the duration by 54%, total antibiotic use by 46% and decreased all-cause mortality by 39%. (Low Zinc Status: A new risk factor for pneumonia in the elderly? . 2010 Jan; 68(1): 30–37.)


    Selenium is an essential co-factor of Glutathione peroxidase in stopping inflammation. It has been shown in multiple studies to significantly reduce the mortality rate due to viral infections. Selenium and Zinc have been combined in clinical trials leading to a significant reduction in respiratory infections. (Impact of trace elements and vitamin supplementation on immunity and infections in institutionalized elderly patients: a randomized controlled trial. MIN. VIT. AOX. geriatric network. Arch Intern Med. 1999; 159(7):748–754.  A deficiency of Selenium in parts of China where the soil is most deficient was found to be associated with an increase rate of mortality due to COVID-19.* 

    Significant clinical benefits of selenium supplementation have also been demonstrated in other viral infections, including HIV-1 [where a negative correlation between selenium status and mortality has been established]; in liver cancer linked to hepatitis B; and in patients with “epidemic hemorrhagic fever” that was successfully treated with oral sodium selenite, giving an overall 80% reduction in mortality. Selenium appears relevant to a number of evolutionarily distinct viruses, via potential immunomodulatory effects that are fully consistent with the many essential roles of selenium in the immune system. (Association between regional selenium status and reported outcome of COVID-19 cases in China; The American Journal of Clinical Nutrition, Published: 28 April 2020

    *These statements have not been evaluated by the Food and Drug Administration. this product is not intended to diagnose, treat, cure or prevent any disease.

    Immune Boost Suggested Use

    • Adults: Take 4 capsules (200,000IU Vitamin A) once daily for 2 days
    • Children 12 months and older: 4 capsules  (200,000iu) once daily for 2 days.
    • Infants 6-11 months: 2 capsules (100,000iu) once daily for 2 days.
    • Infants 1-6 months: 1 capsule (50,000iu) once daily for 2 days.

    Repeat the immune boosting dose below every 4 weeks during seasonal or epidemic immune challenges. For children and infants, dissolve in liquid, yogurt, applesauce, etc. For Adults with a severe immune challenge, the dose may be taken for a maximum of 5 days in a row.


    Do not take if you are pregnant or planning to be pregnant in the next 6 months. Vitamin A excess and deficiency may cause birth defects. Take only as directed.

    Customer Reviews

    Based on 1 review
    R. Rush
    Awesome supplement

    At the beginning of COVID, I wanted to take all steps to stay healthy and give my body all the help I could in fighting this deadly disease. I've been under Dr Hansen's care for many years and trust him explicitly!! In explaining my concerns Dr Hansen recommended the once monthly Immune Boost along with D3 and Phytobiotics. I'm happy to report that I've stayed healthy and have had the peace of mind that if I did contract COVID that it wouldn't be fatal. Thank you Dr Hansen for your passion and dedication.