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Vitamin A benefits, dosage, and deficiency

What is vitamin A good for, and what is the best time to take it?

ingredients 04-vitamin-A illustration
Sophie Medlin
Sophie Medlin
Head of Nutritional Research
July 26, 2022
6 min read

Vitamin A is popular in skincare products, but it’s also one of the essential micronutrients that we all need to survive. So what does vitamin A do? In this article, we’ll look at vitamin A benefits, whether you can have too much, and how we use it in the Smart Supplement.

Article breakdown

What is vitamin A good for?

Vitamin A is a fat-soluble vitamin, found in a variety of foods. It’s essential for the proper functioning of the immune system and has many benefits as for normal vision, reproduction, and the skin. In fact, it has become something of a trendy ingredient in skincare products over the past decade.

The best foods for vitamin A

Vitamin A is present in a wide variety of food sources, including:

  • Beef liver—there is about 5070mcg of vitamin A in 100g of beef liver.

  • Sweet potato—there is about 1403mcg of vitamin A in a baked sweet potato

  • Spinach—there is about 570mcg of vitamin A in 100g of spinach.

  • Carrots—there is about 460mcg of vitamin A in 150g of carrots.

  • Avocado—there is about 90mcg of vitamin A in an avocado.

  • Eggs—there is about 75mcg of vitamin A in an egg.

There are two types of vitamin A that you’ll find in food—preformed vitamin A in animal products, and provitamin A, mainly found in plants, which is converted into retinol in the body. The most common form of provitamin A is beta carotene, which gives carrots their orange colour.

What are the benefits of taking vitamin A?

As we aren’t able to produce vitamin A in the body, it’s vital that we get enough from outside sources. For many people, a healthy, balanced diet will provide the right amount of vitamin A, but supplements are also an option if you’re worried that you might not get enough from food.

Is it ok to take vitamin A everyday?

Yes... but not a lot! Whereas many nutrient reference values (NRVs) are measured in milligrams, the NRV for vitamin A is 800 micrograms a day—less than 1mg in total.

In the Heights Smart Supplement, there is 151mcg (equal to 2 boiled eggs or 2 cups of baked beans). This is 19% of the recommended amount.

Can I have too much vitamin A?

As vitamin A is fat-soluble, anything that isn’t used by the body is stored in the fat and the liver. This means that we are more susceptible to vitamin A toxicity than toxicity from water-soluble vitamins, like vitamins B6, B12, and C. Large doses taken in a short amount of time can have acute effects, including blurry vision and nausea.

Research also suggests that consistent large doses of vitamin A over many years may have health consequences later in life, like making bones more brittle. In general, you should aim to stay below 1500mcg of vitamin A each day and not have liver more than once a week. Very large doses of vitamin A can have more acute effects, including blurry vision and nausea.

Who should not take vitamin A?

While one of the key benefits of vitamin A is its role in reproductive health, large quantities should be avoided altogether during pregnancy, as they can have an impact on the health of the unborn baby.

You should stay away from foods that contain high amounts of vitamin A (such as liver) if you are pregnant, or trying to conceive.

When is the best time to take vitamin A?

As vitamin A is fat-soluble, rather than water-soluble, it’s essential that you take it with some form of fat. Otherwise, your body won’t be able to absorb the vitamin. For this reason, it’s usually advised that you take a vitamin A supplement with a meal. However, if the supplement itself contains fats (for example, the omega-3 oils in the Smart Supplement), you can take the supplement at any time of day.

What are the benefits of vitamin A?

While it’s important to be aware of how much vitamin A you’re having, and to not overdo it, it’s still an essential vitamin with all sorts of benefits for your brain and body.

Here are the main health benefits of vitamin A.

What are the 5 major functions of vitamin A?

  1. Helps to maintain the immune system

  2. Keeps skin healthy

  3. Protects vision in dim light

  4. Promotes bone health

  5. Supports cognitive function

Vitamin A may also help reduce the risk of certain age-related illnesses—one 18-year study of more than 4,000 men linked long-term supplementation to the slowing of cognitive decline.

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Vitamin A benefits for skin

Evidence suggests that Vitamin A applied topically can work to reduce the appearance of find lines and wrinkles, and help combat acne, by stimulating collagen production. A diet high in vitamin A has also been found to prevent cell damage and skin aging.

What are the signs of a vitamin A deficiency?

In Western Europe and the United States, vitamin A deficiencies are rare. However, they can be more common in other parts of the world. Mild vitamin A deficiencies are unlikely to manifest as much more than fatigue, but more severe cases can lead to problems with the eyes (including night blindness) and dry skin and hair.

How we use vitamin A in the Smart Supplement

At Heights, we've formulated the Smart Supplement with vitamin A from retinol acetate, a natural form that can be absorbed easily and allow you to feel the full benefits of vitamin A. You can be sure that:

  • Each dose contains 19% of the NRV for vitamin A.

  • Our vitamin A is pure and quality-tested.

  • Everything is manufactured in small batches.

  • It meets many common dietary and lifestyle practices: It's gluten-free, 100% plant-based, allergen-free and contains absolutely zero GMOs, contaminants, fillers or colourants.


We used these sources when writing this article.

  • Smart Supplement
  • Braincare Journal
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© 2022
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* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease