There’s no shortage of ways to boost your immune system, but one of the most effective is a vitamin called Vitamin A.
Vitamin A is found in many fruits and vegetables, but it’s particularly concentrated in liver (and other organ meats), eggs and butterfat. In fact, much of our vitamin A today comes from synthetic sources rather than natural ones.
Vitamin A has been shown to boost the immune system by increasing production of antibodies and white blood cells that fight off viruses and bacteria. It may also help protect against certain cancers. There is some evidence that it helps prevent heart disease as well, but more research needs to be done before we can be sure about this effect.
Vitamin A For Viruses
Completely Stop Viral Infections Without Help From Your Doctor
When you get a bacterial infection, conventional doctors typically give you antibiotics. But when you get a virus, like the common cold, they might still give you antibiotics (even though they won’t help). Or they will tell you to rest, drink fluids, and wait it out. There’s usually not much they can offer. They tell you to just wait until your immune system takes over. This might cost you a few days of missed work, but usually it’s not a big deal – unless the virus is serious. When it is, there still isn’t much conventional doctors can do, other than support your immune system in its battle.
But there’s very simple treatment that you can do at home without the help of your doctor. This simple treatment can wipe out a viral infection and get you back on your feet quickly. Unfortunately, some conventional researchers make fighting viruses all too difficult. For example, researchers at Washington University School of Medicine working with mice discovered a way to both increase their immune system and attack a protein that helps viruses replicate. While this one-two punch helped the mice fight off a serious virus, it’s really not this difficult. In their study, published in Nature Immunology, the researchers figured out a way to strengthen the body’s interferon signaling system, which plays a major role in the immune system’s ability to fight off viruses.
While they’re still a ways off from developing a cure for the common cold, this research is promising, as viruses can be a major health hazard when they’re severe. As I’ve said in the past, drugs may play a role in fighting extremely serious viruses. But for most cases of the common cold, you really don’t need this complicated science. It’s really much, much easier to fight a virus.
Treating a Virus Naturally
Viruses are pieces of genetic code that invade your cells and use the DNA in your cells to replicate themselves. That’s how they cause infections. Of course, an intact immune system will eventually stop this replication process. When that happens, the infection is over. The good news is you can take an inexpensive, safe, and easily obtained vitamin that can stop viral replication faster. And when you stop viral replication, you get better much faster.
One of the most basic ways that your immune system stops viral replication is through the action of special molecules called cytokines. Your immune cells make a variety of cytokines. They are the key to an optimally functioning immune system. Perhaps the most important cytokine in respect to viral infections is interferon, and it turns out that Vitamin A stops infections by stimulating interferon.
Here’s How the Researchers Made the Discovery
They took a culture of cells treated with vitamin A and exposed them to the measles virus. As expected, the virus was unable to infect the cells because the virus was unable to replicate.
Then they did the experiment again, only this time they exposed the cells beforehand to antibodies that prevented the cells from making interferon. They found that these cells became infected and that the immune-enhancing effects of vitamin A were wiped out. Their conclusion was that vitamin A prevents the measles virus from replicating by stimulating the production of interferon.
But it doesn’t stop with the measles. Large doses of vitamin A work in all viral infections. This is because the replication for all viruses is inhibited by interferon. This includes flu viruses, cold viruses, herpes viruses, and even hepatitis viruses. All of them.
As a result, I recommend that you take vitamin A every day. I take 25,000 units per day. Children should take less, about 5,000 units per day. Just doing this simple thing will reduce your chances of getting the viruses that are always going around. But I have to tell you two warnings about vitamin A.
The first is that some people are very sensitive to vitamin A even in these doses. It is uncommon, but it does happen. If you are taking this dose of vitamin A and several weeks or months later you start getting headaches, nausea, bone aches, or a rash, you may be one of those people. I have seen it happen twice in my career, so I know it can happen, but it is very uncommon at a dose of 25,000 units.
Here’s Some More Comforting Information
Chronic vitamin A toxicity is not lethal and is completely reversible 100% of the time. All you have to do is to reduce the dose. So as long as you feel good while taking it, there is no reason for concern. Additionally, while I am on the topic of vitamin A, let me also mention beta-carotene.
Beta-carotene is a vitamin A precursor. That means that it can be converted into vitamin A after you eat it. But even though it can be converted into vitamin A, it cannot cause vitamin A toxicity. That is because the body will stop converting it to vitamin A once the levels start to get high. The only thing that excessive beta-carotene can do is to temporarily turn the skin a mild orange color. This will revert to normal once the dose is decreased.
One last thing. Pregnant or nursing women should not take more than 5,000 units per day. Doses higher than 8,000 units have been associated with birth defects. This association has not been seen with beta-carotene. And, finally, people with liver or kidney disease should take no more than 5,000-10,000 units.
Also, it’s still possible that you may get a viral infection even if you’re taking preventive doses of vitamin A. If you do, the next thing you need to do is to immediately start taking very large doses. I recommend 100,000 units, three times a day for 7-10 days, or until the infection is over. Although this is a very large dose of vitamin A, it is entirely safe because you will be taking it only until the infection is gone. And studies show that the acute toxic dose of vitamin A is over five times greater than this dose. I have been successfully using this strategy for over 30 years with no problems (other than the aforementioned sensitivities).
vitamin a benefits
Vitamin A is the generic term for a group of fat-soluble compounds highly important for human health.
They’re essential for many processes in your body, including maintaining healthy vision, ensuring the normal function of your immune system and organs and aiding the proper growth and development of babies in the womb.
It’s recommended that men get 900 mcg, women 700 mcg and children and adolescents 300–600 mcg of vitamin A per day (1Trusted Source).
Vitamin A compounds are found in both animal and plant foods and come in two different forms: preformed vitamin A and provitamin A.
Preformed vitamin A is known as the active form of the vitamin, which your body can use just as it is. It’s found in animal products including meat, chicken, fish and dairy and includes the compounds retinol, retinal and retinoic acid.
Provitamin A carotenoids — alpha-carotene, beta-carotene and beta-cryptoxanthin — are the inactive form of the vitamin found in plants.
These compounds are converted to the active form in your body. For example, beta-carotene is converted to retinol (an active form of vitamin A) in your small intestine (2Trusted Source).
Here are 6 important health benefits of vitamin A.
Vitamin A is essential for preserving your eyesight.
The vitamin is needed to convert light that hits your eye into an electrical signal that can be sent to your brain.
In fact, one of the first symptoms of vitamin A deficiency can be night blindness, known as nyctalopia (3Trusted Source).
Night blindness occurs in people with vitamin A deficiency, as the vitamin is a major component of the pigment rhodopsin.
Rhodopsin is found in the retina of your eye and extremely sensitive to light.
People with this condition can still see normally during the day, but have reduced vision in darkness as their eyes struggle to pick up light at lower levels.
In addition to preventing night blindness, eating adequate amounts of beta-carotene may help slow the decline in eyesight that some people experience as they age (4Trusted Source).
Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world. Though its exact cause is unknown, it’s thought to be the result of cellular damage to the retina, attributable to oxidative stress (5Trusted Source).
The Age-Related Eye Disease Study found that giving people over the age of 50 with some eyesight degeneration an antioxidant supplement (including beta-carotene) reduced their risk of developing advanced macular degeneration by 25% (6Trusted Source).
However, a recent Cochrane review found that beta-carotene supplements alone won’t prevent or delay the decline in eyesight caused by AMD (7Trusted Source).
Eating adequate amounts of vitamin A prevents the development of night blindness and may help slow the age-related decline of your eyesight.
Cancer occurs when abnormal cells begin to grow or divide in an uncontrolled way.
As vitamin A plays an important role in the growth and development of your cells, its influence on cancer risk and role in cancer prevention is of interest to scientists (8Trusted Source, 9Trusted Source).
In observational studies, eating higher amounts of vitamin A in the form of beta-carotene has been linked to a decreased risk of certain types of cancer, including Hodgkin’s lymphoma, as well as cervical, lung and bladder cancer.
Yet, though high intakes of vitamin A from plant foods have been associated with a reduced risk of cancer, animal foods which contain active forms of vitamin A aren’t linked in the same way.
Similarly, vitamin A supplements haven’t shown the same beneficial effects (16Trusted Source).
In fact, in some studies, smokers taking beta-carotene supplements experienced an increased risk of lung cancer.
At the moment, the relationship between vitamin A levels in your body and cancer risk is still not fully understood.
Still, current evidence suggests that getting adequate vitamin A, especially from plants, is important for healthy cell division and may reduce your risk of some types of cancer (20Trusted Source).
Adequate vitamin A intake from whole plant foods may reduce your risk of certain cancers, including Hodgkin’s lymphoma, as well as cervical, lung and bladder cancer. However, the relationship between vitamin A and cancer is not fully understood.
Vitamin A plays a vital role in maintaining your body’s natural defenses.
This includes the mucous barriers in your eyes, lungs, gut and genitals which help trap bacteria and other infectious agents.
It’s also involved in the production and function of white blood cells, which help capture and clear bacteria and other pathogens from your bloodstream.
This means that a deficiency in vitamin A can increase your susceptibility to infections and delay your recovery when you get sick (21Trusted Source, 22Trusted Source).
In fact, in countries where infections like measles and malaria are common, correcting vitamin A deficiency in children has been shown to decrease the risk of dying from these diseases (23Trusted Source).
Having enough vitamin A in your diet helps keep your immune system healthy and function at its best.
Acne is a chronic, inflammatory skin disorder.
People with this condition develop painful spots and blackheads, most commonly on the face, back and chest.
These spots occur when the sebaceous glands get clogged up with dead skin and oils. These glands are found in the hair follicles on your skin and produce sebum, an oily, waxy substance that keeps your skin lubricated and waterproof.
Though the spots are physically harmless, acne may have a serious effect on people’s mental health and lead to low self-esteem, anxiety and depression (24Trusted Source).
The exact role that vitamin A plays in the development and treatment of acne remains unclear (25Trusted Source).
It has been suggested that vitamin A deficiency may increase your risk of developing acne, as it causes an overproduction of the protein keratin in your hair follicles.
This would increase your risk of acne by making it more difficult for dead skin cells to be removed from hair follicles, leading to blockages.
Some vitamin-A-based medications for acne are now available with a prescription.
Isotretinoin is one example of an oral retinoid that is effective in treating severe acne. However, this medication can have serious side effects and must only be taken under medical supervision.
The exact role of vitamin A in the prevention and treatment of acne is unclear. Yet, vitamin-A-based medications are often used to treat severe acne.
The key nutrients needed for maintaining healthy bones as you age are protein, calcium and vitamin D.
However, eating enough vitamin A is also necessary for proper bone growth and development, and a deficiency in this vitamin has been linked to poor bone health.
In fact, people with lower blood levels of vitamin A are at a higher risk of bone fractures than people with healthy levels (30Trusted Source).
Additionally, a recent meta-analysis of observational studies found that people with the highest amounts of total vitamin A in their diet had a 6% decreased risk of fractures (30Trusted Source).
Yet, low levels of vitamin A may not be the only problem when it comes to bone health. Some studies have found that people with high intakes of vitamin A have a higher risk of fractures as well (31Trusted Source).
Even so, these findings are all based on observational studies, which cannot determine cause and effect.
This means that currently, the link between vitamin A and bone health is not fully understood, and more controlled trials are needed to confirm what has been seen in observational studies.
Bear in mind that vitamin A status alone does not determine your risk of fractures, and the impact of the availability of other key nutrients, like vitamin D, also plays a role (32Trusted Source).
Eating the recommended amount of vitamin A may help protect your bones and reduce your risk of fractures, though the connection between this vitamin and bone health is not fully understood.
Vitamin A is essential for maintaining a healthy reproductive system in both men and women, as well as ensuring the normal growth and development of embryos during pregnancy.
Rat studies examining the importance of vitamin A in male reproduction have shown that a deficiency blocks the development of sperm cells, causing infertility (33Trusted Source, 34Trusted Source).
Likewise, animal studies have suggested that vitamin A deficiency in females can impact reproduction by reducing egg quality and affecting egg implantation in the womb (33Trusted Source).
In pregnant women, vitamin A is also involved in the growth and development of many major organs and structures of the unborn child, including the skeleton, nervous system, heart, kidneys, eyes, lungs and pancreas.
Yet, though much less common than vitamin A deficiency, too much vitamin A during pregnancy can be harmful to the growing baby as well and may lead to birth defects.
Therefore, many health authorities recommended that women avoid foods that contain concentrated amounts of vitamin A, such as pâté and liver, as well as supplements containing vitamin A during pregnancy.
Adequate amounts of vitamin A in the diet are essential for reproductive health and the healthy development of babies during pregnancy.
Vitamin A is a fat-soluble vitamin, which is stored in your body. This means that excess consumption can lead to toxic levels.
Hypervitaminosis A is caused by consuming too much preformed vitamin A through your diet or supplements containing the vitamin.
Symptoms can include nausea, dizziness, headaches, pain and even death.
Though it can be caused by excessive intake from the diet, this is rare compared to overconsumption from supplements and medications.
Additionally, eating a lot of provitamin A in its plant form doesn’t carry the same risks, as its conversion to the active form in your body is regulated (37Trusted Source).
Eating high amounts of the active form of vitamin A from animal foods, medications or supplements can be toxic. Excessive consumption of provitamin A from plant foods is unlikely.
Vitamin A is vital for many important processes in your body.
It’s used to maintain healthy vision, ensure the normal functioning of your organs and immune system, as well as establishing normal growth and development of babies in the womb.
Both too little and too much vitamin A could have negative effects on your health.
The best way to ensure you get the balance right is to consume vitamin-A-rich foods as part of your normal diet and avoid supplementing with excessive amounts.