What it is
Vitamin A refers to a family of fat-soluble vitamins. Retinol (sometimes referred to as “preformed vitamin A”) is the primary bioactive form of vitamin A, but various carotenoids are also in the vitamin A family. Carotenoids, such as beta-carotene, are molecules that can be converted to retinol in the body.
What it does
Vitamin A plays roles in immune function, reproduction, communication between cells, and maintaining normal vision. It also helps the heart, lungs, and liver maintain normal function.
The recommended intake of vitamin A (in “retinol activity equivalents,” which account for the relative inefficiencies of converting the various carotenoids into retinol) is 900mcg per day for men, and 700mcg per day for women who aren’t pregnant or lactating. Pregnancy and lactation can increase intake requirements for vitamin A.
The safe upper limit for vitamin A intake is 3000mcg per day.
Likelihood of tracking completeness: Very low
Vitamin A is not a nutrient that food manufacturers are required to disclose on nutrition labels. The vast majority of food and beverage manufacturers do not voluntarily list vitamin A content on nutrition labels, so most branded products in the MacroFactor database lack information on vitamin A. So, if you’d like to accurately track your vitamin A intake, you’ll need to make a point of mostly tracking “common foods,” which come from research-grade databases that have full nutrient reporting.
For more on when you can track using branded foods versus common foods when you’re trying to accurately monitor your intake of particular nutrients, you should check out this article.
Likelihood of insufficient intake: High
Most people in developed countries consume less than the recommended intake of vitamin A. In the US, the average intake of Vitamin A is around 600mcg/day for women, and 700mcg/day for men.
For more on nutrients with a greater likelihood of insufficient or excessive intake, you should check out this article.
Signs of deficiency
Signs of a vitamin A deficiency include night blindness, increased rates of illnesses and infections, and anemia.
Liver has by far the highest vitamin A concentrations, but fatty fish, eel, yogurt, and dairy products are also great sources of vitamin A. Vegan sources of vitamin A are generally rich in carotenoids, rather than retinol. Great options include lettuces, peppers, sweet potatoes, spinach (and other leafy greens), pumpkin, and carrots.
If you’d like to learn more about micronutrients generally, there’s a five-part series on the MacroFactor website you might enjoy.