Vitamin A is the unsung hero for the immune system, eye health, and much more (1), (2), (3), (4). As far as immunity goes, many people automatically reach for vitamin C and vitamin D, but forget about the power of vitamin A (1), (5).
While vitamin D and C are also crucial to improve the function of the immune system, vitamin A is as well (1), (5). Vitamin A is a micronutrient that protects the epithelium and mucous membranes in the body (6), (7). It even can have a therapeutic effect on the healing of infectious diseases (8), (9).
It acts as an anti-inflammatory agent, which makes it crucial at enhancing immunity (10). This micronutrient also plays a significant role in cellular immune responses (1), (11).
Vitamin A is fat-soluble, so too much can build up in the body. However, it is rare to get too much vitamin A from food alone (4), (6), (12). If you take in too much vitamin A, it would be through supplementation (13).
Summary: Vitamin A is a fat-soluble nutrient responsible for boosting the immune system and also acts as an anti-inflammatory agent. Since it is a fat-soluble vitamin, too much intake could cause health issues. It is rare to get too much vitamin A from food alone.
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Health Benefits of Vitamin A
Vitamin A is a micronutrient that helps to carry out many functions in the body. Find out the many health benefits of vitamin A and how it can specifically help many bodily functions below.
1. Improves Vision
Improving vision is one of the pertinent health benefits of vitamin A (2). It not only improves vision health overall, but it may prevent the chances of developing age-related macular degeneration (14), (15). Age-related macular degeneration causes significant vision loss for the elderly.
It is vital to understand that the more vitamin A you get does not mean it is necessarily better. Too much vitamin A can cause just as much harm as too little (13).
A few other vitamins are also essential in combination with vitamin A to improve vision and prevent macular degeneration later in life. These vitamins include vitamins C and E (16). They show to be the most beneficial at reducing the chances of macular degeneration, even if it runs in your family.
Try not to get too focused on family diseases. There is promising hope in the field of epigenetics that shows that even if a disorder runs in your family, it does not mean you will inherit it. Epigenetics states that you may have the power to change your gene expression (17).
Summary: Vitamin A is very helpful for improving vision health. In combination with vitamins C and E, it helps to improve vision and prevent macular degeneration later in life. Age-related macular degeneration can cause vision loss. Focus on consuming a balanced diet rich in these vitamins if you’re looking to boost eye health.
2. Necessary for Reproduction
Another essential role of vitamin A is through reproduction (18). Pregnant women need to get a healthy amount of vitamin A to help prevent complications (12).
Premature infants are at a high risk of being deficient in vitamin A, along with young children, mostly in developing countries (19), (20).
That is mostly because mothers in developed countries typically have enough vitamin A in their breastmilk, while other poorer countries may not (21).
Pregnant women require more vitamin A to help the fetus fully develop (21), (22). If you are pregnant, make sure you are getting adequate amounts of vitamin A in your diet and through a prenatal vitamin.
Summary: Vitamin A is essential for reproductive health. Pregnant women need extra vitamin A to help their baby develop fully. If you are pregnant or nursing, make sure to consume enough vitamin A in your diet and take a prenatal vitamin.
3. Boosts Immunity
Many automatically think of vitamin C for immunity, but vitamin A is just as essential to keeping your immune system strong and healthy (1), (5).
Vitamin A protects mucous membranes and many tissues throughout the body (6), (7). It is a necessary micronutrient to make sure your immune system is always functionally well.
When your immune system is healthy and functioning well, your chance of developing colds, viruses, and other illnesses can drastically decrease (23).
You can get all the vitamin A you need from a healthy balanced diet, but supplementing vitamin A in a multivitamin can also be beneficial for some (4).
One thing to keep in mind with keeping Vitamin A levels normal is that it may be better absorbed when taken with vitamin E (24). So it may be beneficial to determine if you are low in either nutrients.
Summary: Vitamin A is very important for a strong immune system. It helps to protect mucous membranes and tissues in the body. Most often, you can reach your vitamin A needs through food, but taking a multivitamin with vitamin A may be beneficial for some. Vitamin E can help increase vitamin A absorption, so be sure to keep this in mind when trying to boost vitamin A intake.
4. Prevents Measles
While measles does not usually affect developed countries as much lately, measles can be a contributor to death in developing countries (25). Vitamin A deficiency is a contributor to those who have measles (5).
If a child and over age 1 develop measles, the World Health Organization recommends taking oral supplementation of 200,000 international units (IU) for two days to bring their levels back up (26). That dosage can significantly reduce the risk of mortality among children in developing countries (27). This is only recommended for children with measles living in areas of the world where vitamin A deficiencies is common (26).
In areas like the United States, research is lacking about the connection between vitamin A and measles (6). However, severe vitamin A deficiency is known to cause measles.
Children that get measles are not only at risk of that but because they are low in vitamin A, symptoms can lead to blindness from malnutrition (6), (28).
Vitamin A is a crucial micronutrient that needs to stay at adequate levels to prevent measles, as well as blindness that can ensue as well.
Summary: Severe vitamin A deficiency is known to cause measles. In developed nations, research is lacking in regards to vitamin A and measles. However, the World Health Organization recommends taking oral supplementation of 200,000 IU for two days to increase levels in children over age 1 with measles in countries with high rates of vitamin A deficiency. Children who get measles with low vitamin A are at risk for blindness and other health issues.
5. May Lower Risk of Lung Cancer
Vitamin A may also play a role in reducing the risk of lung cancer.
In one study, smokers and nonsmokers showed lower rates of lung cancer in those that ate more vitamin A-rich foods (29). Participants who eat more foods high in carotenoids from many different fruits and vegetables have lower risk of lung cancer. However, supplements of vitamin A and beta-carotene have not been found to be protective against lung cancer (30), (31).
The reason vitamin A may help to lower the risk of lung cancer is due to the protective nature it can have on lung tissue. It can also help to slow the development or progression of pulmonary disease (32).
Respiratory disease and lung cancer are rampant across the globe, affecting millions of people every year (33). Eating a healthy balanced diet is one step to preventing disease, including lung cancer. Another crucial step is to quit smoking, pay attention to your environmental toxins as much as possible, and examine other lifestyle factors that can negatively affect your health (34).
Summary: Vitamin A from foods may help prevent lung cancer. It contains protective nutrients that support healthy lung tissue. However, supplements of vitamin A do not have the same protective benefits as vitamin A from foods. Eating a balanced, nutrient-rich diet and smoking cessation can help reduce overall risk of developing lung cancer.
6. Developing a Healthy Heart
Vitamin A is necessary for overall development, and the heart is a part of that. Many studies show that vitamin A plays a direct role in heart formation during the development of the embryo and fetus in pregnancy (35), (36).
These findings can help to decrease the risk of cardiovascular complications in newborns as well as problems that may develop for them later in life.
Summary: The heart is also an organ that benefits from adequate vitamin A intake. Many studies show vitamin A plays a role in heart formation during pregnancy, which can help to decrease risk of cardiovascular complications in newborns. More research is needed to assess vitamin A’s role in overall heart health.
7. May Lower Risk of Prostate Cancer
Many observational studies show a possible connection between a lower risk of prostate cancer and eating more foods high in vitamin A. More research is necessary for this, though.
Lycopene is a carotenoid that gives many fruits and vegetables their color, like tomatoes, watermelon, and guava. All these foods are also high in vitamin A. Carotenoids can be changed into vitamin A in the body, and they can be a powerful antioxidant against cancer (37). However, while foods high in vitamin A may be beneficial, supplements of vitamin A have not been shown to reduce risk of prostate cancer (38).
There may be a connection to eating more vitamin A-rich foods and preventing prostate cancer. However, more research is needed to understand if there truly is a connection between vitamin A and prostate cancer.
Eating a healthy diet is always the right choice to avoid prostate cancer. Remember that vitamin A protects and strengthens the immune system, so it can never hurt to add more of it through food (1).
Summary: Vitamin A may play a role in reducing risk of prostate cancer. Many vitamin A-rich foods also contain lycopene, a carotenoid that gives many fruits and vegetables their red/orange color. Tomatoes, watermelon, and guava are a few to name. Carotenoids contain powerful antioxidants known to fight cancer. Vitamin E, selenium, calcium, and vitamin D are also cancer-fighting nutrients.
Where to Get Vitamin A from Food?
There are many different foods that are high in vitamin A. Check out the list below to see where you can start adding more vitamin A to your diet.
Foods high in vitamin A include (4):
- Red bell pepper
- Cod liver oil
- Fortified breakfast cereal
- Beef liver
- Dairy-Many types of cheese
- Sweet potatoes
- Many other orange and yellow fruits and vegetables
There are a plethora of vitamin A-rich foods you can start adding to your diet to boost eye health, enhance your immune system, prevent many types of cancer, maintain a healthy heart, and more .
Be sure to add more of these foods to your diet to reap all the health benefits from vitamin A.
Potential Health Risks from Too Much Vitamin A
Vitamin A is a fat-soluble vitamin, which means it builds up in the body over time if you take too much (39). It is almost impossible to get too much vitamin A from food alone (4). Overdose can potentially happen when you take too many vitamin A supplements or too high of a dosage (39).
The potential health risks from taking too much vitamin A through supplementation include (4), (39):
- Blurry vision, or other vision problems
- Sensitivity to light
- Dry skin
The recommended daily intake of vitamin A is 900 mcg for adult men and 700 mcg for adult women (4). Pregnant women require more vitamin A so the fetus can fully develop without complications (4).
The upper limit of vitamin A is 3,000 mcg per day, but that is typically not ideal daily unless otherwise prescribed by a doctor (4), (12).
Summary: Too much vitamin A can build up in the body and cause toxicity. Symptoms include blurry vision, nausea, vomiting, sensitivity to light, and dry skin. Generally, taking additional supplements of vitamin A causes toxicity. It is often rare to overdose on vitamin A through food alone. Men should get 900 mcg and women 700 mcg per day. The upper limit of vitamin A is 3,000 mcg per day.
Vitamin A is a crucial micronutrient that the body needs to maintain eye health, a healthy heart, better skin, and it can even help to prevent some cancers.
There are many foods you can start to include in your diet if you feel you are not getting enough vitamin A.
This vitamin is typically safe for many to consume daily through food and lower supplement dosages.
Be sure to include plenty of vitamin A-rich food in your diet to get all the health benefits from this potent micronutrient.