Vitamin A is an essential nutrient required for healthy vision, brain function, skin, bones, and immune response. As an antioxidant, it plays a protective role by countering inflammation and oxidative stress. Some of the best sources of vitamin A are fish, eggs, dairy products and orange plant-based foods, such as mangoes, squash, pumpkin, and carrots. As a supplement, vitamin A is highly bioavailable, and it helps ensure you’re getting enough regardless of what you eat from day to day. There are two forms of vitamin A: retinol and beta-carotene. Retinol is found in animal-based and is immediately assimilated by the body. Beta-carotene is found in plant foods, and it gets converted through the digestion process into a usable form of vitamin A. Mounting evidence points to the disease-preventing roles both forms of vitamin A play throughout the body.
- Promotes Strong Bones
Vitamin A helps synthesize osteoblasts, which are the structural cells that form new bone and are responsible for depositing calcium into bones. Insufficient vitamin A has been shown to help reduce your assimilation of calcium, which in turn lowers bone density. Research has linked vitamin A deficiency to an increased risk of bone fractures and osteoporosis–a condition characterized by bone tissue loss that results in brittle, easily breakable bones. According to some studies, however, too much vitamin A supplementation may reduce bone density. As long as you stay below the tolerable upper limit of 10,000 IU per day when taking vitamin A supplements, you won’t have a problem.
- Protects Eye Health
Your eyes critically depend on vitamin A. In fact, changes in your vision are typically the first signs of vitamin A deficiency. You might experience night blindness and dry eyes, as well as inflammation of the cornea, which can lead to scarring. Sufficient levels of vitamin A are required for preventing age-related macular degeneration–the leading cause of vision loss in senior citizens.
Vitamin A drops can help provide relief from eye dryness, which is why vitamin A is added to many over-the-counter eye drops. In a 2011 study, researchers found that a synthetic form of vitamin A slowed the progression of not only age-related macular degeneration but also of Stargardt’s disease, which causes blindness in young people. These findings show that the importance of vitamin A for maintaining your vision can’t be ignored.
- Supports Your Immune System
Vitamin A regulates several genes involved in immune response, making it an essential nutrient for fighting cancer and autoimmune diseases, as well as common infections like colds, flus and stomach viruses. In fact, vitamin A is so important for illness prevention that when 100,000 Colombian children were given vitamin A supplements, the Colombian government estimated that over $340 million in medical spending was avoided due to significantly reduced instances of diarrhea, malaria, and other conditions.
Vitamin A helps synthesize T helper cells, which help immune cells respond to infection. It also helps develop B cells, a type of white blood cell that releases antibodies to kill pathogens. Whereas deficiency weakens your immune response, maintaining adequate levels of vitamin A helps your body fight off bacteria and viruses.
- Helps Lower Inflammation
Oxidative stress occurs throughout the body when cells and tissue are damaged by free radicals, which steal electrons from healthy molecules. Antioxidants, such as vitamin A, counter this by giving an extra electron to free radicals, rendering them stable. By reducing oxidative stress, vitamin A lowers inflammation in the body. Chronic inflammation makes you susceptible to many diseases. However, reducing inflammation is shown to help lower your risk for cancer and neurodegenerative diseases, such as Alzheimer’s, dementia and Parkinson’s. Research has also shown that vitamin A supplementation helps manage several inflammatory conditions, including inflammatory skin conditions, bronchopulmonary dysplasia, and cancer.
- May Help Fight Cancer
Vitamin A works to help control malignant cells in the body, including cancer cells. A 2014 study published in Biomedicine found that vitamin A, in the form of retinol, helped suppresse the growth of cancer cells in the skin, liver, lungs, breasts, and prostate.
When it comes to cancer prevention, research shows that carotenoids found in plant foods help lower your risk of cancer. However, no evidence has been able to link vitamin A supplementation, either in the form of beta-carotene or retinol, directly to cancer prevention. While vitamin A supplements can help with cancer treatment, you still want to eat plenty of fruits and vegetables that are high in carotenoids to help prevent cancer.
- Improves Your Skin
Vitamin A plays a role in every aspect of your skin’s health, including wound healing and generating new skin cells, as well as fighting acne, skin cancer and the effects of aging. Deficiency can cause poor complexion, acne, and eczema. Besides helping you keep skin problems at bay, vitamin A also helps beautify the skin and slow the progression of aging. By boosting the production of collagen, a protein responsible for skin elasticity and firmness, vitamin A can prevent and reduce wrinkles and sagging.
- Helps Lower Blood Glucose Levels
Vitamin A deficiency and the inability to absorb or metabolize vitamin A have been linked to the development of diabetes. Studies show that adequate vitamin A intake protects against insulin resistance, whereby cells fail to respond normally to insulin–the hormone responsible for glucose metabolism. By preventing insulin resistance, vitamin A can help keep blood sugar stable and play a role in preventing diabetes.
Researchers have found that vitamin A plays a vital role in the production of beta cells, which are cells in your pancreas that create insulin. Vitamin A is also responsible for maintaining the health of beta cells. In a study on the relationship between vitamin A and diabetes, scientists blocked the vitamin A receptors on beta cells so that they couldn’t absorb vitamin A. They found that the beta cells deteriorated and produced 30 percent less insulin than beta cells that absorbed vitamin A. This same tendency is seen in people with diabetes, who have impaired insulin production.
The study also found that vitamin A protected beta cells against inflammation, and vitamin A deficiency increased beta cell death. The mounting research suggests that vitamin A helps prevent and reverse diabetes by boosting the synthesis and health of beta cells.
- Antioxidant support
Vitamin A possesses antioxidant effects that can keep the body healthy. In a review of the research, scientists from St. Boniface General Hospital Research Center in Canada reported that vitamin A has demonstrated antioxidant activities that can help reduce the risk of heart disease. The scientists published their review in a 1999 edition of Free Radical Biology and Medicine. More specifically, an Indian study in a 2001 publication of The Journal of the Association of Physicians of India, found that vitamin A supplementation reduced markers of oxidative stress among patients with heart disease. It appears that vitamin A has antioxidant effects that are beneficial for heart health.
Getting Your Vitamin A
Because vitamin A is fat-soluble, eating it with fat improves assimilation. Protein is also required for vitamin A absorption, and low protein levels can increase your risk of deficiency. Studies have found that the body’s ability to utilize vitamin A also depends on sufficient zinc levels. Vitamin A supplements can help you prevent or reverse the deficiency. However, you need to be sure not to take more than 10,000 IU of vitamin A to avoid toxicity.