Vitamin A

Vitamin A is essential for vision, growth, and immune health, acting as an antioxidant to protect cells from damage. Found in foods like spinach, dairy, and carrots, it’s often best obtained naturally. While supplements can help those with specific deficiencies or conditions, getting too much vitamin A can lead to serious side effects, including liver damage and birth defects. It’s important to balance your intake and consult with a doctor if you’re pregnant or on certain medications.

What is Vitamin A?

Vitamin A, which includes retinol and retinoic acid, is a key nutrient that plays a big role in keeping your vision sharp, supporting growth, helping with cell division, reproduction, and boosting your immune system. It also has antioxidant properties, meaning it might help protect your cells from damage caused by free radicals. These are unstable molecules your body produces when breaking down food or when you’re exposed to things like tobacco smoke and radiation. Free radicals are thought to contribute to various health problems, including heart disease and cancer.

Where Can You Find Vitamin A?

You can find vitamin A in a variety of foods. It’s in spinach, dairy products, and liver, as well as in foods rich in beta-carotene, like green leafy vegetables, carrots, and cantaloupe. Your body can convert beta-carotene into vitamin A, giving you another way to get this important nutrient.

Should You Take a Vitamin A Supplement?

For most people, a healthy diet provides enough vitamin A. However, there are situations where a supplement might be necessary, especially if you have a limited diet or a health condition that increases your need for vitamin A, like pancreatic disease, eye issues, or measles. But, if you’re considering taking vitamin A for its antioxidant benefits, remember that supplements may not be as effective as getting antioxidants from your food.

How Much Vitamin A Do You Need?

The recommended daily amount of vitamin A is 900 micrograms (mcg) for adult men and 700 mcg for adult women.

What Does the Research Say?

Here’s what studies suggest about vitamin A:

• Acne: High doses of vitamin A supplements don’t seem to have much of an effect on acne.
• Age-Related Macular Degeneration (AMD): A major study found that people at high risk for advanced AMD could lower their risk by 25% with a specific mix of vitamins, including beta-carotene. However, it’s unclear how much of that benefit came specifically from beta-carotene.
• Cancer: The link between vitamin A supplements and a reduced risk of lung, prostate, and other types of cancer is still unclear.
• Measles: Vitamin A supplements are recommended for children with measles, especially those at risk of vitamin A deficiency. Some research suggests that these supplements might reduce the risk of death from measles.
• Vitamin A Deficiency: People with low vitamin A levels benefit the most from supplements. Although this deficiency is rare in the United States, it can lead to anemia and dry eyes.

Beyond taking it orally, vitamin A is also used in creams to reduce fine wrinkles, treat acne, and smooth out skin texture.

Our Take: Proceed with Caution

For most people, getting vitamin A from food is the best approach. The benefits of vitamin A supplements, especially for their antioxidant properties, aren’t as clear as those from naturally occurring sources in food. It’s also important to know that too much vitamin A can be harmful. For example, excessive vitamin A during pregnancy has been linked to birth defects.

Safety and Side Effects

Overdoing it on vitamin A can be dangerous. A single large dose—over 200,000 mcg—can lead to symptoms like:

• Nausea
• Vomiting
• Vertigo
• Blurry vision

Taking more than 3,000 mcg a day of oral vitamin A supplements over a long period can cause:

• Bone thinning
• Liver damage
• Headaches
• Diarrhea
• Nausea
• Skin irritation
• Joint and bone pain
• Birth defects

If you’re pregnant or planning to become pregnant, talk to your doctor before taking vitamin A, as too much can lead to birth defects.

Interactions with Other Medications

Vitamin A can interact with certain medications, so it’s important to be aware of potential risks:

• Anticoagulants: Taking vitamin A supplements with blood thinners might increase your risk of bleeding.
• Bexarotene (Targretin): Using vitamin A supplements while on this cancer drug can up the chances of side effects like dry, itchy skin.
• Hepatotoxic Drugs: High doses of vitamin A combined with other liver-damaging drugs can increase the risk of liver disease.
• Orlistat (Alli, Xenical): This weight-loss drug can reduce your body’s ability to absorb vitamin A from food, so your doctor might suggest a multivitamin.
• Retinoids: Avoid using vitamin A supplements along with oral retinoid medications, as this could lead to dangerously high levels of vitamin A in your blood.

In short, while vitamin A is vital for your health, getting the right amount—mainly through a balanced diet—is key to avoiding potential risks.