Vitamin A Palmitate: What You Should Know

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When you think of vitamin A, you probably imagine a single nutrient. But the term actually refers to a family of chemical compounds. One of these is vitamin A palmitate, a pre-formed version of vitamin A that is easily absorbed by the body. Found naturally in animal foods and synthetically in supplements, it supports your vision and immunity. However, there are concerns surrounding excessive use.

What Is It?

You can sort the family of vitamin A compounds into two categories:

  • Pre-formed vitamin A: This category includes retinol and retinyl esters.  
  • Pro-vitamin A compounds: This category includes three different carotenoids that can be converted to retinol in your body. The most prominent of these three is beta-carotene, the pigment that lends carrots and sweet potatoes their bright orange color.

Vitamin A palmitate—also called retinyl palmitate—is a specific type of retinyl ester from the pre-formed vitamin A category. In animals and humans, it serves as a natural storage form of vitamin A. Supplement and skin care manufacturers also produce a synthetic version for use in different products.

Comparing to Carotenoids

The pre-formed versions of vitamin A—including vitamin A palmitate—have a higher bioavailability compared to carotenoids. In other words, your body finds it easier to convert them to a biologically active form.

Though many assume that retinol itself is the active nutrient in the body, it is actually a transport form. It is activated via a two-step process to retinal and then retinoic acid.

Both vitamin A palmitate and carotenoids like beta-carotene need to be converted to retinol first before it can be converted to retinoic acid.

 However, the process is more efficient for vitamin A palmitate compared to a carotenoid.

In fact, the conversion process for beta-carotene from food is lower than you might expect. You would need about 12 micrograms of beta-carotene to achieve the same physiological effect as one microgram of retinol itself.

Sources 

You’ll spot vitamin A Palmitate in a number of products including:

  • Food. Because it serves as a storage form of vitamin A in animals, you’ll find vitamin A palmitate in those foods—especially liver and fish. Dairy manufacturers also fortify milk with this form, as it is more stable in milk compared to the retinol form.
  • Supplements. You may see vitamin A palmitate in both over-the-counter vitamin pills, as well as injectable vitamin shots administered by a physician.
  • Skincare products. Products like moisturizers and anti-aging treatments may contain this form of vitamin A, as some research suggests it helps reduce fine lines and wrinkles.
  • Eye drops: Researchers have used vitamin A palmitate in eye drops to treat dry eye with moderate levels of success, however a bulk of the current research is on animals.

Beneficial Uses

There are a few scenarios where vitamin A palmitate supplementation might be implemented with beneficial effects:

Vitamin A Deficiency
Vitamin A palmitate supplementation—whether oral or injectable—may be used to treat a vitamin A deficiency. Though it’s uncommon in the United States, certain groups are more likely to experience this deficiency:  

  • Children and pregnant women in developing countries. This can be attributed to a lack of vitamin A-rich food sources in the diet, as well as more frequent diarrhea infections that exacerbate vitamin A losses.
  • Premature infants.  When babies are born early, they typically have lower liver stores of vitamin A, increasing their risk of deficiency in early life.
  • People with cystic fibrosis. Those with cystic fibrosis have a more difficult time absorbing fat soluble vitamins (which includes vitamin A).

    Vitamin A deficiency is a leading cause of night blindness, and can also lead to increased risk of infections and mortality.

    Measles
    Vitamin A deficiency is associated with an increased risk of severe measles. In areas where deficiency is prominent, the World Health Organization recommends that children diagnosed with measles are given a high-dose oral vitamin A supplement for two days. This may reduce the risk of death from measles.

    Tuberculosis
    Vitamin A deficiency has been linked to increased tuberculosis risk, mainly among people living with family member with tuberculosis or those with HIV. In fact, one study found a striking ten fold increase in tuberculosis risk among vitamin-A deficient household contacts. Another case-control study found that people with the highest dietary vitamin A intake had the lowest risk of contracting tuberculosis.

    Controversial Uses

    Supplements and Cancer

    Early research suggested that retinoic acid—what vitamin A palmitate is eventually converted to—was theoretically involved in cancer prevention at the cellular level. And observational studies suggested that diets high in beta-carotene were associated with reduced lung cancer risk.

    However, these theories have not proven true when it comes to vitamin A palmitate (or other forms of vitamin A) supplementation:

    • Breast cancer. A 2013 review did not find any consistent benefits associated with Vitamin A supplements as far as cancer prevention.
    • Lung cancer. When studies administered beta-carotene and vitamin A palmitate supplements, some actually found an increased lung cancer risk among smokers or former smokers.
    • Overall cancer risk. A 2017 meta-analysis found vitamin A supplements resulted in an 16 percent increase in cancer risk, as well as an increased risk of cancer mortality.

    Unless you have a vitamin A deficiency or struggle with some of the issues mentioned earlier, it seems prudent to stick with vitamin A intake from food rather than supplements. While you don't have to worry about a low-dose supplement (like vitamin A in a daily multivitamin), it's probably best to nix any high dose vitamin A palmitate supplements (especially if you have a family history of cancer).

    Sunscreen and Cancer

    Some groups are also urging caution when it comes to sunscreen products with vitamin A palmitate. Organizations like the Environmental Working Group are concerned about skin cancer risk in light of data released from the National Toxicology Program study.

    That particular study compared hairless mice swabbed with a sunscreen that contained vitamin A palmitate to mice swabbed with a control lotion. After a year of controlled UV exposure, the mice that were coated in the sunscreen with vitamin A palmitate were found to have a higher risk of skin cancer.

    Keep in mind that a lone animal study doesn’t meet the burden of proof. And as with all animal studies, there are always differences between the way something may react in an animal model versus a human model. The American Academy of Dermatology maintains that vitamin A palmitate is safe in sunscreen.

    If you’re worried about the safety risk, though, simply choose a sunscreen that does not contain this ingredient. Only 10-15 percent of current sunscreens and moisturizers on the market feature vitamin A palmitate in the ingredients, so you shouldn’t have too much trouble locating an option without it.

    Side Effects

    Meeting the recommended dietary allowance for vitamin A is essential for your overall health. But like most concepts in nutrition, you can have too much of a good thing.

    The current tolerable upper intake level (UL) for vitamin A is 3,000 micrograms retinol activity equivalents (RAE) for adults. You may also see this upper limit expressed as 10,000 International Units (IU).

    Keep in mind that this UL applies to pre-formed vitamin A, like that which you get from animal foods and supplements with vitamin A palmitate, retinol, or other retinyl esters. It does not include the beta-carotene you get through fruits and vegetables.

    According to the Mayo Clinic and the National Institute of Health, long-term excessive vitamin A intake above the UL can cause side effects like:

    • Liver damage
    • GI upset, including nausea and diarrhea
    • Skin irritation
    • Bone loss
    • Joint pain
    • Increased intracranial pressure
    • Dizziness
    • Coma

    Taking too much vitamin A palmitate in pregnancy has also been linked to birth defects, including malformations of the heart, skull, or lungs. If you’re currently taking any vitamin A supplements in addition to your normal prenatal vitamin, it’s probably worthwhile to put them on pause until you can chat with your doctor. Keep in mind that dosages vary, so not all vitamin A supplements will lead to a dangerous level of consumption. But better to be safe and check with your physician first.

    Sources:

    Boudreau MD, Beland FA, Felton RP, Fu PP, Howard PC, Mellick PW, Thorn BT, Olson GR. Photo‐co‐carcinogenesis of Topically Applied Retinyl Palmitate in SKH‐1 Hairless Mice. Photochemistry and Photobiology. 2017 Jul;93(4):1096-1114. doi:10.1111/php.12730

    Environmental Working Group. The Problem with Vitamin A. 2018.

    National Institutes of Health: Office of Dietary Supplements. Vitamin A. 2018.

    O’Byrne SM, Blaner WS. Retinol and retinyl esters: biochemistry and physiology: Thematic Review Series: Fat-Soluble Vitamins: Vitamin A. Journal of Lipid Research. 2013;54(7):1731-1743. doi:10.1194%2Fjlr.R037648

    Schwingshackl L, Boeing H, Stelmach-Mardas M, et al. Dietary Supplements and Risk of Cause-Specific Death, Cardiovascular Disease, and Cancer: A Systematic Review and Meta-Analysis of Primary Prevention Trials. Advances in Nutrition. 2017;8(1):27-39. doi: 10.3945%2Fan.116.013516