What do vitamins do? Find out all you need to know with our easily digestible guide

Vitamins and minerals are nutrients our body needs in small amounts to work properly and stay healthy. Most of us should get all the nutrients we need through a varied and balanced diet, although some people may need to take supplements.

If you think this might be you, and you find yourself scratching your head in the vitamin aisle, you’re not alone. It’s time to decode those little tubs and tubes and discover what’s inside them.

Vitamins and supplement sales are forecast to reach £559 million by 2025, but do we actually need to supplement our diet with added vitamins? Whatever your question, our handy guide makes getting the answers as easy as (vitamin) A, B, C.

What are vitamins & what do they do?

Whenever you hear the word ‘vitamins’, your mind probably jumps straight to chunky tubs of red chewy gummies or screw-top bottles of translucent yellow capsules.

While there are different vitamin supplements available to support a healthy lifestyle, the best way to get all the vitamins and minerals you need is by eating a healthy, balanced and varied diet.

Taking supplements should never replace eating a wide variety of foods in the right proportions and amounts to achieve a healthy body weight. Your diet should include wholegrain foods, fruit and vegetables, some dairy or dairy alternatives, some beans, pulses, fish, meat, eggs and other protein, small amounts of unsaturated fats and plenty of water.

And remember, if you are taking any medicines, are pregnant or breastfeeding, or have a long-term health condition, always check with your doctor or pharmacist before taking supplements.

What makes up a healthy, balanced diet?

The Eatwell Guide breaks down the proportions of the main food groups that form a healthy, balanced diet:

• Eat at least five portions of a variety of fruit and vegetables every day

• Base meals on potatoes, bread, rice, pasta or other starchy carbohydrates; choosing wholegrain versions where possible

• Have some dairy or dairy alternatives (like soya drinks); choosing lower fat and lower sugar options

• Eat some beans, pulses, fish, eggs, meat and other proteins (including two portions of fish every week, one of which should be oily)

• Choose unsaturated oils and spreads and eat them in small amounts

• Drink six to eight cups or glasses of fluid a day

When it comes to foods and drinks high in fat, salt or sugar, it’s best to have these less often and in small amounts.

What are the 13 essential vitamins?

There are 13 essential vitamins – A, C, D, E, K and the B vitamins (B1, B2, B3, B5, B6, B7, folic acid (B9) and B12). If we don’t get enough of these, we're more vulnerable to becoming unwell.

Vitamin A

• Helps look after your skin

• Helps maintain normal vision

• Helps keep your immune system working properly

• Supplements should be avoided during pregnancy

Good news – getting our daily vitamin A is easy as there are lots of foods rich in it. Carrots, green, leafy vegetables, cheese, eggs and oily fish are perfect examples and milk is a good source of the vitamin.

Consider: Centrum MultiGummies Immunity Support

• Contains 30 gummies

• Orange flavour

• Two a day

These orange gummies are packed with zinc and vitamins A, C and D, to help maintain normal immune function.

Vitamin B

There are eight types of B vitamins (who knew?) and each plays an important role in keeping you ticking over.

• Thiamin (vitamin B1) – helps the body break down and release energy from food and keep the nervous system healthy. Found in peas, bananas, oranges, nuts and wholegrain bread.

• Riboflavin (vitamin B2) – helps keep skin, eyes and the nervous system healthy and helps the body release energy from food. Found in milk, eggs and fortified foods including breakfast cereals

• Niacin (vitamin B3) – helps the body release energy from food and keeps the nervous system and skin healthy. Found in meat, fish, wheat flour and eggs.

• Pantothenic acid (vitamin B5) – helps the body release energy from food. Found in varying amounts in almost all vegetables, wholegrains and meats, such as chicken and beef.

• Vitamin B6 – found in a wide range of foods, including pork, chicken, fish and peanuts.

• Biotin (vitamin B7) – found in most foods at very low levels.

• Folate and folic acid (vitamin B9) – found in broccoli, brussels sprouts and leafy, green vegetables.

• Vitamin B12 – helps keep the nervous system healthy and releases energy from food. Found in milk, cheese, eggs and some fortified breakfast cereals.

Consider: Boots Vitamin B Complex

• Contains 90 tablets

• One a day

• Lactose-free

Suitable for those following a vegetarian or vegan diet, this blend of B vitamins help top up your daily levels and contribute to the reduction of tiredness and fatigue.

Vitamin C

• Helps keep skin, bones and cartilage healthy

• Helps protect cells

Add more of this vitamin to your diet by enjoying foods like oranges, broccoli, red and green peppers, berries and even brussels sprouts (they’re not just for Christmas).

Consider: Sambucol Liquid Immuno Forte

• Size: 230ml

• Adults and children 12+ years – 10mls (2 teaspoons) daily

• Children 3 to 12 years – 5ml (1 teaspoon) daily

Contains black elderberry plus zinc and vitamin C, which helps maintain normal immune system function.

Vitamin D

• Helps control the body’s calcium and phosphate to maintain healthy bones, teeth and muscles

• Helps support the immune system

Oily fish, red meat, egg yolks and some fortified foods contain the sunshine vitamin and our bodies make it from sunlight, but getting enough from food and the sun can be tricky (although less so during the summer months).

How much sun do you actually need to get enough? Find out more in our vitamin D guide.

Consider: Boots Vitamin D 10µg

• Contains 90 tablets

• One a day

Free from artificial colours, flavours and preservatives, the vitamin D in these tablets help regulate the amount of calcium and phosphate in the body, ultimately helping to keep bones, teeth and muscles healthy. One tablet a day can also help maintain the normal function of your immune system.

Vitamin E

• Protection of cells

Eating wheat germ (found in lots of cereal products), using plant oils like rapeseed and olive oils, and snacking on nuts and seeds are great ways to add more vitamin E into your diet.

If you eat a healthy and balanced diet, you should be able to meet your daily vitamin E requirements, particularly since it is stored in the body, but a good supplement may also help support levels.

Consider: Boots Selenium with Vitamins A, C and E

• Contains 60 tablets

• One a day

The selenium and vitamins C and E found in these tablets help protect cells from oxidative stress. The tablets are also free from artificial colours, flavours and lactose.

Vitamin K

• Helps with healthy blood clotting

• Helps keep bones healthy

While small amounts can be found in meat and dairy, if you’re looking to find good sources of vitamin K, go for leafy greens, such as spinach, cereal grains and vegetable oils.

It’s handy to know that your body stores vitamin K, so you don’t need to worry about including it in your diet every day.

Vitamin K may interfere with some medicines taken to thin the blood. Always check with your doctor or pharmacist before taking supplements if you are taking any medicines or have a long-term health condition.

Read more about vitamin K and what it does in our guide.

Consider: BetterYou D3000 + K2 Vitamin D + K2 Daily Oral Spray

• Size: 12ml

• 3 sprays a day

If you do want to seek out a supplement to support levels, you may want to consider this handy spray. It’s ideal if you don’t like taking pills and also provides a 25mcg dose of vitamin D3.

What about iron & calcium?

These are both minerals. Like vitamins, they help your body do its thing.


• Helps make red blood cells, which move oxygen around the body

• Helps reduce tiredness and fatigue

• Supports normal cognitive function

Foods rich in iron include red meat, beans, nuts, dried fruits, wholegrains and dark, leafy greens, such as kale.

Consider: Solgar Gentle Iron 20mg

• Contains 90 capsules

• One a day

The iron in these tablets can help reduce tiredness by supporting energy levels and this formula contains iron bisglycinate, a form of iron which is better tolerated by sensitive stomachs.


• Helps maintain healthy bones and teeth

• Helps with normal muscle function

• Helps blood to clot normally

Try including foods like fish that you eat the bones of (such as sardines), milk, cheese and other dairy products in your diet to make sure you’re getting plenty of calcium.

If you’re vegetarian or vegan, there are plenty of choices including soya beans, fortified soya milk, green, leafy vegetables such as spinach, nuts and calcium-set tofu. Check out our guide to vegetarian and vegan diets for more ideas and advice.

Consider: Boots Calcium with Vitamin D

• Contains 30 tablets

• Two a day

Free from artificial flavours and preservatives, the calcium in these tablets help maintain healthy bones and teeth.

Do I need to take vitamins & supplements?

Most of us can get nearly all the vitamins and minerals we need from the foods we eat, with food supplements intended to add to the vitamin and mineral levels we get from a varied diet that includes plenty of fruit and vegetables. Taking supplements isn’t a replacement for eating well.

However, there are some people who may benefit from taking a vitamin food supplement*.

To find out if you’re one of them, speak to your pharmacist or GP. The below may also provide a helpful guide.

Breastfed babies

Our little ones have delicate skin, so protecting them from the sun’s rays is super important.

Our bodies make vitamin D naturally when exposed to sunlight, which means it’s harder for babies to get enough of the sunshine vitamin.

The UK government recommends that breastfed babies from birth to one year of age have a daily supplement containing 8.5-10 micrograms of vitamin D all year round.

Formula-fed babies won’t need a vitamin D supplement until they have less than 500ml (about a pint) of infant formula a day because infant formula already contains vitamin D.

Children aged six months to five years

Growing kids can be fussy eaters from time to time and it can be tricky to make sure they get enough vitamins A, C and D.

The UK government recommends that all children aged six months to five years take a daily supplement containing vitamins A, C and D, with the exception of babies who are having more than 500ml (about a pint) of infant formula a day, because formula is fortified with vitamins A, C and D.

Pregnant women, or women trying to get pregnant

Folic acid is important for the development of a healthy foetus. It can help reduce the chance of neural tube defects, such as spina bifida**.

If you’re trying to get pregnant, it’s recommended you take a daily supplement of 400mcg of folic acid when you’re trying and during the first 12 weeks of pregnancy.

It’s also recommended that pregnant and breastfeeding women aim to get 10 micrograms of vitamin D a day. As it can be difficult for people to get enough vitamin D from their diet alone, everyone should consider taking a daily supplement containing 10 micrograms of vitamin D during the autumn and winter months.

Avoid taking cod liver oil or any supplements containing vitamin A (retinol) when you're pregnant as too much vitamin A could harm your baby.

People who aren’t regularly exposed to the sun

The body creates vitamin D from direct sunlight on the skin when outdoors, so unless you spend the colder months of the year jetting off to sunnier shores, getting the sunlight needed to make enough vitamin D in the UK from October to March is tricky.

It’s advised that everyone aged four and over considers taking a 10mcg vitamin D supplement during the autumn and winter months.

A year-round supplement containing 10mcg of vitamin D is recommended if:

• You wear clothes that cover most of your skin when outdoors

• You are housebound or rarely go outside

• You have dark skin – for example, you have an African, African-Caribbean or south Asian background

Those following a vegan diet

Some nutrients can be more difficult to get via a vegan diet. These include vitamin D, vitamin B12, iodine, selenium, calcium and iron.

Most people get vitamin B12 from animal sources, such as meat, fish and dairy products.

Sources for vegans are limited and a vitamin B12 supplement may be needed. Vegan food sources include foods fortified with B12, such as breakfast cereals, unsweetened soya drinks and yeast extract, such as Marmite, and nutritional yeast flakes.

How much should I take?

If you decide to take supplements, make sure you take the recommended amount.

Have a close read of the label as it states the nutrient reference value (NRV) that the supplement contains.

The NRV is shown as a percentage and helps show the contribution towards daily intakes.

We’re all different, so your doctor may advise you to take another amount based on what’s best for you.

Questions about vitamins or supplements? Worried you might have a vitamin deficiency? Have a chat with your GP or pharmacist.

Is it possible to have too much of a vitamin?

Most people won’t have to worry about consuming too many vitamins through their diet alone.

If you supplement with vitamins, it’s good to know what and how much you’re putting in your body as you really can have too much of a good thing.

Vitamins C and B are water-soluble vitamins. This means the body can’t store them and you pass any excess you don’t need in urine.

Vitamins A, D, E and K are fat-soluble vitamins, meaning the body stores them for long periods. Taking high doses of fat-soluble vitamins is a no-no, as this can lead to health problems. Although less likely, regularly taking an excess of water-soluble vitamins can also be harmful.

Always make sure to stick to label or packaging instructions when it comes to figuring out how much you should take, unless your doctor advises you differently. It’s also worth checking with your doctor or pharmacist initially, especially if you’re combining different products.

Feel inspired? Shop Boots’ full range of vitamins and supplements. Unsure which ones to take? Take this vitamins quiz for an extra helping hand.

*Food supplements are intended to supplement the diet and should not be regarded as a substitute for a balanced and varied diet or a healthy lifestyle.

**Supplemental folic acid intake increases maternal folate status. Low maternal folate status is a risk factor in the development of neural tube defects in the developing foetus. The beneficial effect is obtained with a supplemental folic acid daily intake of 400 μg for at least one month before and up to three months after conception.