Vitamin A: Retinol vs. Beta Carotene, and the Best Food Sources

Vitamin A is a nutrient your body needs for eyes, skin, immune defense, and bone health. It comes in two very different forms.

One form, called retinol, comes from animal foods and is ready for your body to use right away. The other form, beta carotene, comes from plants and your body has to convert it into retinol first.

Retinol is called preformed vitamin A. It is found only in animal foods.

Beta carotene is a plant pigment called a carotenoid. Your body converts it into retinol only as needed, which makes it harder to overdose on compared to retinol.

A 2024 review looked at how well the body absorbs vitamins from animal versus plant foods. It found that retinol from animal sources has higher bioavailability than beta carotene and other carotenoids from plants^[8].

This means your body has to work harder to get usable vitamin A from plant foods. It also means eating a variety of both animal and plant sources may help you meet your needs more reliably^[8].

A 2011 review of vitamin A status in European teens found real differences in blood retinol and beta carotene levels by region and by diet pattern.

This shows that food choices and geography both shape vitamin A status in real populations^[6].

Vitamin A supports several systems at once.

• Vision, especially adjusting to low light
• Immune function and defense against infection
• Skin and mucous membrane health
• Gut lining health and gut microbiome balance^[1]
• Bone formation and maintenance^[4]

A 2021 review found that vitamin A helps maintain the gut lining and interacts with the gut microbiome. This suggests vitamin A status may affect digestive health as well as immunity^[1].

A 2024 review on bone health found that vitamin A, alongside other vitamins, plays a role in bone remodeling. The authors noted this role is still less studied than vitamin D's role in bone health^[4].

Vitamin A and beta carotene are often studied alongside other antioxidants for eye health, especially age related macular degeneration (AMD).

A 2023 meta analysis looked at antioxidant vitamin and mineral supplements for slowing AMD progression.

It found that certain antioxidant combinations, including vitamin A and beta carotene, may modestly slow progression in some people with existing AMD, though the evidence is not strong for everyone^[3].

Vitamin A has also been studied as part of nutrition support for wound healing.

A 2024 meta analysis of oral nutrition supplements for chronic wounds found that supplement formulas containing vitamin A, along with protein and other nutrients, were linked to better wound healing outcomes in some studies^[5].

This does not mean vitamin A alone heals wounds. It was studied as one ingredient in a larger nutrition formula^[5].

People with cystic fibrosis often have trouble absorbing fat soluble vitamins, including vitamin A, because of pancreatic issues.

A 2018 meta analysis looked at vitamin A and beta carotene supplementation in people with cystic fibrosis.

It found that supplementation is common practice, but the trial evidence for its benefits is still limited and more research is needed^[2].

Other groups who may be at higher risk of low vitamin A include people with limited diets, digestive disorders that affect fat absorption, or very low intake of animal foods and colorful vegetables^[6][8].

Signs of low vitamin A can include trouble seeing in dim light, dry eyes, dry skin, and more frequent infections.

For most people eating a varied diet, food sources cover vitamin A needs well.

A large 2022 evidence review for the US Preventive Services Task Force looked at vitamin and mineral supplements, including vitamin A, for preventing heart disease and cancer in the general population.

It found insufficient evidence that supplementing with vitamin A prevents these diseases in people without a diagnosed deficiency^[7].

Because retinol builds up in the body, high dose supplements carry a risk of toxicity over time. Beta carotene from food does not carry this same risk, since the body converts it only as needed^[8].

Animal sources tend to be richest in retinol.

• Beef or chicken liver
• Fish liver oils
• Eggs
• Full fat dairy, like milk, butter, and cheese

Plant sources provide beta carotene, which your body converts to retinol.

• Sweet potatoes
• Carrots
• Spinach and other dark leafy greens
• Butternut squash
• Cantaloupe and mangoes

Eating both animal and plant sources across the week is a practical way to cover vitamin A needs, given the bioavailability differences between the two forms^[8].