The supplements you do and don't need

Adding a vitamin or mineral supplement into your daily routine can feel like a simple way to protect yourself, but in most cases the the evidence to support their use isn't overwhelming.

A study of more than 20,000 adults published in the medical journal BMJ Open in 2020 found no difference in diseases or health conditions between those who took multivitamin supplements and those who didn't.

Despite this supplement sales are booming and the UK industry is worth around £500m a year. 

However, the same study found that taking supplements can make you feel better. Supplement users reported better overall health compared with non-users by 30%, known as a placebo effect. 

You might think there's no harm in taking supplements if they make you feel better, but they're not risk-free and can be pricey, too, so you'll want to know it's worthwhile.

Supplements are also not a shortcut to good health – taking a pill isn't a substitute for a healthy, balanced diet and it's important to always check with a health professional if you have any medical conditions, or are taking medications before adding supplements to the mix, in case of possible interactions.

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The supplement everyone needs

There is one supplement that everyone is recommended to take in the UK and that's vitamin D. 

Vitamin D is important for your immune health. It's also important for your bones and teeth – and a deficiency means that you can't absorb the calcium from food and so can lead to weakened bones or rickets in children. 

It's found in some food such as oily fish, egg yolks, red meat, liver, mushrooms that have been grown in sunlight, and fortified breakfast cereals or spreads, but it is hard to get enough from your diet alone. 

Our main source of vitamin D is from sunshine, but in the winter months in the UK, you can't get enough from sunshine.

Some people are at higher risk of vitamin D deficiency so should take a supplement all year round. These include people with darker skin, people who cover their skin fully when outside and those who are inside a lot.

Find out more in our full Vitamin D guide, including where to get the cheapest supplements and how vitamin D pills, gummies and sprays compare.

Other important vitamins and minerals

Iron

Why you need iron

Iron plays an important role in red blood cells, which carry oxygen around your body. It's also important for immune health and cognitive function.

If you have an iron deficiency, you can feel tired, have a lack of energy, be short of breath, look pale and be more vulnerable to infections.  

Where you find iron

Iron is found in red meat and offal. It's also in chicken and fish, but in lower amounts. Iron from animal sources is most easily absorbed.

Plant-sources of iron include kidney beans, chickpeas, nuts, dried apricots and fortified breakfast cereals. When taking a plant-source of iron you should have it with a food or drink containing vitamin C as this will help its absorption. 

Avoid drinking tea and coffee or eating bran-containing cereals at the same time as they inhibit iron absorption.

Do you need an iron supplement?

Most people should be able to get all the iron they need from their diet. 

Children need higher levels of iron as they're growing. Women also have higher requirements when they menstruate or are pregnant. 

Iron supplements can have unpleasant side effects, including constipation and stomach aches.

Vitamin B12

Why you need vitamin B12

Vitamin B12 helps make red blood cells and keeps your nervous system functioning. It also helps release the energy from the food you eat.

Where you find vitamin B12

Vitamin B12 is mainly found in food of animal origin, including meat, fish, milk, cheese and eggs.

Non-animal sources include yeast extract and fortified breakfast cereals.

Do you need an vitamin B12 supplement?

If you eat the above foods, you're unlikely to need a supplement, even if you're vegetarian. 

However, if you're vegan you may need a vitamin B12 supplement.

A vitamin B12 deficiency can leave you tired, lacking energy, feeling confused, having trouble concentrating and having problems with your memory. It can also lead to mouth ulcers.

As we age, our ability to absorb vitamin B12 decreases and deficiencies are common in older adults. If you find you're suffering from the above symptoms, your doctor can check your B12 levels with a blood test and recommend supplements if necessary. 

Find out more in our full guide to vitamin B12 and who needs it.

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Should you take multivitamin or targeted supplements?

Multivitamin supplements typically contain a wide range of vitamins and minerals, including vitamins A, C, D, E and the B-vitamins, as well as iron, calcium, magnesium and zinc. 

They're often targeted to a specific group or condition, although they mostly contain similar ingredients, albeit in different doses. Examples include supplements for vegans, over-50s, pregnancy or immune health. 

Most of these nutrients are easy to find in foods, other than vitamin D. If you eat a healthy, balanced diet and don't exclude any food groups, you're probably getting all the vitamins and minerals you need, and so won't need a multivitamin.

Pregnancy supplements

When you're pregnant you need more folic acid than normal for the first 12 weeks. It's hard to get the necessary amount from diet alone, so you'll need a supplement. 

Folic acid helps to prevent neural tube defects in babies, such as spina bifida. If you're pregnant, or trying to get pregnant, the government advises you to take 400 micrograms (µg) of folic acid each day from conception until the end of the 12th week of pregnancy.

You don't need to take a multivitamin for pregnancy, but if you do, make sure it's a specific pregnancy one. Standard multivitamins contain vitamin A and too much of this can be harmful to a foetus.

Also avoid cod liver oil supplements for the same reason.

Read our guide on 13 things to do if you find out you're pregnant in 2024

Supplements for vegans

A balanced and healthy vegan diet containing a wide range of fruit and vegetables, beans, nuts, seeds and wholegrains should provide most of the nutrients needed. 

For example, it's not true that all vegan diets are lacking in protein. Plant-based sources of protein include lentils, chickpeas, beans, tofu, nuts and seeds.

Meat replacements, such as soya burgers and sausages, are also good sources of protein.

However, there are some nutrients that can be harder to get from a vegan diet, such as iron, iodine and vitamin B12. You'll need to plan your diet to make sure you're getting enough calcium and selenium, too, by including fortified plant milks, green leafy veg and brazil nuts.

Vegan sources of iron

Our bodies don't absorb iron from plant-foods as efficiently as iron from animal foods.

Vegan sources of iron include wholegrains, green leafy vegetables such as kale, peas, lentils and beans, dried fruit and wholegrains. 

Eating these foods alongside a vitamin C source (citrus fruits, potatoes and green leafy veg) will help aid iron absorption.

Vegan sources of calcium

Calcium is found in leafy green vegetables such as kale, as well as figs, almonds, kidney beans, sesame seeds and fortified plant milks.

If you're choosing a plant milk, make sure it has calcium added to it (is fortified) and avoid organic plant milks as they aren't fortified.

Vegan sources of iodine

Iodine is also found in fortified plant milks and in seaweed. However, seaweed is a very concentrated source so you're advised not to eat it more than once a week.

Vegan sources of zinc

Good plant-based sources of zinc include wheat germ, beans, nuts, seeds, mushrooms and fortified breakfast cereals. 

Vegan sources of Omega-3

 Our bodies convert the essential fats in flaxseeds, walnuts, linseeds and vegan omega-3 supplements made from algae into long-chain omega-3 fatty acids.

Vegan sources of vitamin B12

Vitamin B12 is naturally found in animal foods, so it can be difficult to get if you're following a vegan diet. 

However, some foods are fortified with it. These include Marmite and other yeast extract spreads, some breakfast cereals and some plant-based milks.

It might be hard to get enough from these (1.5 micrograms a day), so you may want to consider taking a vitamin B12 supplement. 

Supplements for children

The government advises children aged six months to five years old should take a multivitamin containing vitamins A, C and D each day.

However, if your baby is formula fed (and having more than 500ml a day), they don't need a multivitamin as formula milk is already fortified.

Don't give children adult multivitamins as they contain doses that are too high and don't give more than one supplement at a time as you may double up on some nutrients.

Breastfed babies should take a vitamin D supplement each day from birth, regardless of whether the mother is taking a vitamin D supplement. 

Get more advice on vitamin D for babies and children

Supplements you don't need

Beyond vitamin D, if you're healthy, and eat a varied and balanced diet including meat, fish, dairy products, beans, pulses, nuts, seeds and your five-a day of fruit and vegetables, you're very likely getting all the nutrients you need. 

Popping a pill can feel like an easy option, but evidence shows that you can't replace a healthy diet with a supplement. For example, a diet high in fruit and vegetables is proven to reduce your risk of certain cancers, but there's no evidence that a multivitamin does the same.

There are other supplements on the market that contain ingredients for which there are no proven health benefits.

Glucosamine supplements

Glucosamine is found naturally in your cartilage, ligaments and tendons, and issues with these can cause joint pain.

As a result, it's found in supplements for joint health, mobility and flexibility – but there's not enough evidence to conclusively prove taking glucosamine helps with any of these.

As a result, glucosamine has no authorised health claims. 

Vitamin C, on the other hand, is proven to help support bones and cartilage, and as a result glucosamine supplements often also contain vitamin C. 

All health claims on glucosamine packaging and advertising relating to bones and cartilage are attributable to the vitamin C, and not the glucosamine in the supplement.

Collagen supplements 

Collagen is a protein that keeps your skin strong and elastic, but levels decline with age which has provided an opportunity for collagen supplements.

Unfortunately, consuming collagen doesn't mean it will become collagen in your body. When you consume collagen, your body breaks it down into amino acids and rebuilds it into the proteins you most need. 

The European Food Safety Authority has said that there isn't currently enough evidence to support a health claim that collagen could improve skin health.

More health claims under the microscope in our guide to the health products you don't need

Co-enzyme Q10

Your body makes CoQ10 in your liver and it's also found in foods such as meat and vegetable oils.

It helps provide energy to cells and is an antioxidant.

It's found in supplements with claims relating to improved energy levels, brain function, cholesterol or blood pressure. However, it has no authorised health claims. These supplements often contain other ingredients such as B-vitamins (which do have authorised claims) to enable the product to make these claims.

Vitamin C

Vitamin C is found in many foods, including citrus fruits, strawberries, blackcurrants, peppers, broccoli and potatoes, and it's easy to get what you need through diet.

However, there are lots of vitamin C supplements on the market that contain 1,000mg – more than 20 times what you need in a day – and people often take these to fight colds. 

While vitamin C plays a role in keeping your immune systems healthy, there isn't currently enough evidence that high-dose supplements can keep a cold at bay.

As Vitamin C is a water-soluble vitamin, your body can't store it. Once your body has used what it needs each day it excretes any excess in urine, so you're literally flushing your money down the toilet. 

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Where to buy supplements

Boots, Holland & Barrett and Superdrug all have supplements to suit a range of needs on the high street or online.  

These shops often have offers on their supplement ranges, such as three for two or buy one, get one half price, so it can make sense to stock up one staples such as vitamin D. Just be sure to check use by dates if you do this.

You can buy single nutrient supplements, such as vitamin D, or a multivitamin targeted to your specific needs, such as a supplement for vegans. Often these are available in various formats – these include tablets, capsules, gummies, sprays and liquids. 

You can also buy a range of doses, but bear in mind more doesn't mean better. 

In the case of water-soluble vitamins (B-vitamins and vitamin C), your body can't store any excess so once it's used what it needs it any excess will end up in the toilet. 

For fat-soluble vitamins (A, D, E and K), consuming more than you need over a prolonged period can be problematic. Your body can't excrete excess and so stores it – in the case of vitamin D, this can cause a build up of calcium in your body which can weaken your bones, and damage the kidneys and heart.

You can see how much vitamin or mineral a supplement contains and how much of your daily reference nutrient intake (RNI) it provides. Remember, you'll also be getting nutrients from the food you eat, so try not to take supplements that contain much more than 100% of your RNI (unless advised by a doctor). As well as potentially causing you harm, they will be more expensive and you could be wasting your money.

Be careful about mixing too many different ones, too – for the same reason, it's easier to accidentally take more than you should.