Vitamin A (Retinol)
Vitamin A is an essential nutrient needed for vision, immunity, skin health and the growth and repair of tissues. It comes in two main forms: retinol (found in animal foods and supplements) and beta-carotene (a plant form the body converts into vitamin A as needed).
While small amounts of vitamin A are important, taking too much — especially in supplement form — can be harmful. High doses can affect the liver, bones and, most importantly, pregnancy, where excessive vitamin A can pose significant risks to a developing baby.
Because vitamin A is fat-soluble, the body stores it. This means levels can build up over time, making supplements something to approach with great care. Most people can safely meet their needs through food without requiring extra supplementation.
What It Is
Vitamin A is a fat-soluble vitamin that supports:
vision and eye health
immune function
skin repair
reproductive health
growth and development
Forms of vitamin A:
Retinol — the “ready-made” form found in animal foods and many supplements
Beta-carotene — the plant form, found in colourful vegetables; the body converts it into vitamin A only as needed
This difference matters because retinol is easy to over-consume, while beta-carotene is self-limiting and considered safer.
What It’s Used For
Vitamin A supplements are sometimes considered to support:
skin and barrier health
immune function
vision
reproductive health
However, vitamin A is not a supplement to take casually. Most people can meet their needs through diet, and many multivitamins already contain vitamin A — making accidental overuse possible.
What the Evidence Says
Research shows that vitamin A:
supports normal vision
contributes to immune function
assists with cell growth and repair
plays a central role in embryonic development
But evidence also shows:
high-dose vitamin A can be harmful, especially to the liver and bones
too much retinol during pregnancy can harm a developing baby
liver and cod liver oil contain very high amounts of retinol
smokers should avoid high-dose beta-carotene supplements due to increased cancer risk in studies
the UK adult population typically meets its needs through food
This is why vitamin A supplements should only be used when appropriate and with professional or medical guidance.
When It Can Be Helpful
Vitamin A may be considered when:
a recent blood test shows low vitamin A (rare in the UK)
dietary intake of vitamin A–rich foods is extremely limited
a practitioner or GP has recommended a specific form or dose
certain medical contexts require it under supervision (never self-administered)
Most people do not need vitamin A supplements, and low energy or immune issues rarely relate to vitamin A alone.
When Caution Is Needed
Vitamin A supplementation carries significant risks if used without guidance.
Use extreme caution, and seek advice, if you:
are pregnant or trying to conceive (excess retinol can harm a developing baby)
take skin medications that relate to vitamin A (such as isotretinoin or retinoids)
already take a multivitamin that contains vitamin A
eat liver or liver products regularly
take cod liver oil
consume fortified foods (some plant milks and cereals add retinol)
drink alcohol frequently (vitamin A and alcohol are both processed by the liver)
smoke (high-dose beta-carotene supplements are unsafe for smokers)
Why It’s Not Always the First Step
Vitamin A deficiency is rare in the UK, and symptoms people often associate with low vitamin A — such as dry skin, low immunity or poor night vision — can have many other causes.
Before considering vitamin A supplements, it’s important to:
review diet quality and vegetable intake
check whether other supplements already include retinol
consider lifestyle factors affecting immunity and skin
explore overall nutrient balance (zinc, omega-3, protein, hydration)
avoid self-supplementation if pregnant or trying to conceive
Food-first strategies are not only safer, but often just as effective.
Nutrition Support
Food sources of vitamin A include:
Retinol (ready-made vitamin A):
liver (very high — small amounts only)
eggs
full-fat dairy
oily fish
Beta-carotene (safer plant form):
carrots
sweet potatoes
butternut squash
spinach and kale
red peppers
apricots
The body converts beta-carotene to vitamin A only as needed, making plant-rich diets a safe way to support vitamin A intake.
Supporting vitamin A pathways also involves:
balanced meals with healthy fats (improves absorption)
good gut health
reducing alcohol intake
Food-first is the safest approach.
If You’re Unsure Whether Vitamin A Is Right for You
If you're thinking about vitamin A for skin, immunity or general wellbeing, we can explore your diet, symptoms and lifestyle together — and check whether supplements are appropriate. Vitamin A is one of the nutrients where using the right form, dose and timing really matters.
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