Many people regard vitamin and mineral supplements as a vital health insurance policy – and despite the expert consensus that a balanced diet can provide all your nutritional needs, almost half the UK population regularly buys supplements.

But are we wasting our money?

When it comes to multivitamins, maybe so – a huge US study published last year in the JAMA Network Open journal, based on data from nearly 400,000 healthy adults over 20 years, found that those taking daily multivitamins were no less likely to die prematurely than people who didn’t take them.

‘Overall, evidence suggests a daily multi-vitamin doesn’t have significant benefits for preventing heart disease, cancer or any mor-tality cause,’ says Tim Spector, a professor of genetic epidemiology at King’s College London and co-founder of health app Zoe.

And mega-doses can do more harm than good. ‘Many people assume that because vitamins are essential for optimal health, taking more is always better, but this isn’t the case,’ says Professor Spector. ‘Too much of certain individual vitamins, such as A and E, can increase your risk of poorer health.’

Yet while a balanced diet is great in theory, the latest figures are unequivocal about how poor the average UK diet is. The most recent National Diet and Nutrition Survey shows that 70 per cent of adults eat fewer than the recommended five fruit and veg a day.

Ultra-processed foods (UPFs) – such as ready-meals and most packaged foods – now account for almost 60 per cent of our food intake. For Professor Spector, the rise in UPFs is a cause for national alarm: ‘The more over-processed foods you eat, the more likely you are to have below optimal levels of nutrients.’

Like many experts, he would prefer to address this imbalance through diet. But with a problem this widespread, it’s clear that supplementation will be at least part of the solution for many.

There’s a lot to suggest that the right supplement taken in the right amount at the right time can play a role in good health

Fruit, vegetables and grains now contain around 50 per cent less iron, copper and sodium and up to 40 per cent less magnesium than in the 1940s

Dr Lindsy Kass, a sports and nutrition scientist at the University of Hertfordshire, is a ‘food-first’ advocate, too, but says vitamins can be a useful ‘safety net’ to support a normal diet, especially for those recovering from illness, or with food absorption problems, or on long-term medication or a calorie-restricted diet.

Even for those who eat well, it’s worth bearing in mind that the recommended daily amounts (RDA) of vitamins and minerals are often set at the minimum, and not, according to some experts, at optimum levels for health.

‘There are also nutrients that have always been trickier to get enough of through diet alone,’ says Simon Gaisford, a professor of pharmaceutics at University College London. One is vitamin D, made mainly by the action of sunlight on skin. Many Britons are low in this nutrient, which is essential for the immune system, muscles, bones and teeth.

This is why the NHS recommends taking a vitamin D supplement (see box below) throughout winter. We’re also missing out on key nutrients because even our crops have become less nutrient dense.

‘In the past 80 years, there has been an alarming decline in food quality and a decrease in a wide variety of nutritionally essential minerals thanks largely to intensive farming techniques and poor soil quality,’ says Dr Kass.

Fruit, vegetables and grains now contain around 50 per cent less iron, copper and sodium and up to 40 per cent less magnesium than in the 1940s, reported the International Journal of Food Sciences and Nutrition in 2021.

So there’s a lot to suggest the right supplement taken in the right amount at the right time can play a role in good health.

In the latest of our unique health pullouts, we’ve sifted through all the latest research and spoken to leading experts to create your essential guide to becoming supplement savvy.

THE SUPPLEMENTS PROVEN TO HELP

Half of us take a supplement once a week or more – many in the hope they will help offer relief from a common complaint such as arthritis, insomnia or eczema.

But unlike drugs, which undergo rigorous testing to prove they are effective and safe, food supplements don’t undergo the same checks. A blend to ‘boost energy’ or ‘for healthier hair’ might seem worth trying, but experts say these are often just bog-standard multivitamins with clever branding and inflated prices.

We spoke to specialists in their field to uncover the supplements with the most robust science behind them to show they help with common problems.

JOINT PAIN

Strongest evidence: Turmeric; collagen.

Turmeric: ‘There’s increasing evidence that suggests curcumin [the yellow pigment in turmeric] reduces damaging inflammatory proteins released by our cells and therefore has the potential to help many inflammation-based diseases, including arthritis,’ says Susan Hewlings, a dietitian at Central Michigan University, who has researched the spice.

‘Studies found that taking it as a supplement may provide similar pain relief for arthritis as ibuprofen. But it hasn’t been through rigorous trials.’ Research suggests taking 500mg to 1,000mg per day.

Collagen: The most abundant protein in the body, collagen provides structural support for our connective tissues.

Levels drop with age, but ‘studies suggest that collagen may help regenerate damaged joints’, says Dr Robert Erskine, a reader in neuromuscular physiology at Liverpool John Moores University, who’s conducted collagen research. An analysis of 36 studies, published last year in the journal Orthopaedic Reviews, found that 5-10g daily could help ‘patients suffering from joint pain’, he says. Take it with vitamin C or orange juice to aid absorption.

EYE HEALTH

Strongest evidence: A blend of antioxidants with vitamins C and E, lutein, zeaxanthin and zinc; or omega 3s.

Antioxidant blend: The main cause of vision loss after 50 is age-related macular degeneration (AMD), causing a central blind spot and blurred sight which worsens over time. Studies show that diets low in fruit and veg increase your risk.

‘We know specifically that the antioxidants lutein and zeaxanthin – found naturally in bright-coloured fruit and leafy green veg such as red peppers and spinach – are important for a healthy macula,’ says Dr Elizabeth Hawkes, a consultant ophthalmic surgeon at Cadogan Clinic in London.

While the mix won’t prevent AMD in the first place, ‘two well-respected US studies [AREDS 1 and 2] found that high doses of supplements containing vitamins C and E, lutein, zeaxanthin and zinc could slow down or prevent the progression of the condition’ – volunteers who took the supplements every day for six years ‘had a 25 per cent reduction in the progression of the disease’.

However, the dose is vital: based on the studies, this means 500mg vitamin C, 400 IU (international units) vitamin E, 10mg lutein, 2mg zeaxanthin, 25mg zinc and 2mg copper.

Omega 3s: Found in oily fish and walnuts, studies suggest that these oils prevent and slow macular degeneration, dry eye disease and glaucoma. Most studies used 1-2g a day.

SLEEP PROBLEMS

Strongest evidence: Magnesium.

‘Some studies show magnesium supplements can help fight insomnia,’ says nutrition scientist Dr Lindsy Kass. A review published last year in Cureus: Journal of Medical Science concluded that ‘supplementing magnesium is likely useful in the treatment of insomnia, particularly in those with low magnesium’.

As Dr Kass explains, magnesium aids in muscle relaxation, ‘which can help with dropping off – and recent research shows it also helps regulate the calming GABA neurotransmitter [chemical messenger] that reduces brain activity, making it easier to switch off and fall asleep’. Doses of 200-400mg appear effective.

HEART HEALTH

Strongest evidence: Coenzyme Q10; omega 3s.

Coenzyme Q10: ‘This is an antioxidant that helps generate energy in cells, but has also been found to help lower blood pressure and to reduce sore muscle side-effects related to statin use,’ says Dr Ameet Bakhai, a cardiologist at Spire Bushey Hospital in Hertfordshire.

‘A review of studies in 2018 in the Journal of Current Cardiology found doses of 100-300mg a day can also be useful in those with a weakened heart.’

Omega 3s: ‘These can be useful for lowering triglycerides [blood fats], a contributing factor in heart disease,’ says Dr Bakhai.

He points to a 2024 review in the Future Journal of Pharmaceutical Sciences, which found omega 3s could also reduce cholesterol and inflammation in the arteries ‘which may help keep them healthy and clear’.

As for how much to take: a large study published in the New England Journal of Medicine in 2018 found that giving patients with raised triglycerides (even though they were on statins) 2g of omega 3s twice daily signficantly lowered their risk of heart attack or stroke compared with patients given a placebo.’

SPRAY, PILL OR GUMMY?

Clinical pharmacist Ian Jackson, from Nottinghamshire, explains how to pick the right format for you:

TABLETS: Absorbed slowly and more likely to break down incompletely, which can mean some of the nutrients pass as waste. Tablets need more manufacturing to make them stable, so may use fillers, colours and binders.

CAPSULES: These have a gelatine or vegan tapioca case, which breaks down when passing through the gut, meaning the active contents are absorbed more swiftly and completely than tablets. They’re easier to swallow and some (such as probiotics) have cases formulated to withstand stomach acid, so they release their contents lower down the digestive tract.

SPRAYS: Convenient for children and the elderly who find swallowing tablets difficult. Absorbed through the tissue in the mouth, they enter the bloodstream quickly and avoid the gut altogether. But they can be more expensive.

GUMMIES: These can be attractive for children to take – plus they’re absorbed faster than tablets. But they’re often filled with sugar, sweeteners or colourings.

LIQUID VITAMINS: This formulation means larger doses can be squeezed in. Active ingredients are pre-dissolved so can be absorbed faster and more completely. But check the label for flavourings and preservatives.

FIZZY TABLETS: The nutrients are dissolved by the time you drink them, so are more readily absorbed. But they contain a form of salt, so avoid if you have kidney disease or high blood pressure.

MENOPAUSE

Strongest evidence: Sage leaf; red clover.

Sage leaf: ‘Some herbal remedies can be especially useful for women who don’t want to take HRT or who’ve been advised not to, for example because they’ve had breast cancer,’ says Tania Adib, a consultant gynaecologist at The Lister Hospital in London.

A 2023 research review, published in the International Journal of Community Based Nursing and Midwifery, found that women taking sage (100-300mg daily) experienced significantly fewer hot flushes and noticed improvements in night sweats, sleep quality and forgetfulness.

Red clover: ‘This plant extract can be effective for hot flushes and night sweats,’ says Dr Adib.

‘It contains phytoestrogens – weak plant oestrogens that have been shown to ease overheating and sweating, although not like HRT does.’ Research from 2011, published in the journal Obstetrics and Gynecology International, found it can also help with other menopause-related symptoms such as low libido, anxiety, depression and fatigue.

ECZEMA

Strongest evidence: Vitamin D; omega 3s.

Vitamin D: A 2021 review published in Practical Dermatology found that taking vitamin D could promote a stronger skin barrier.

‘Studies suggest this nutrient can boost the immune response and reduce inflammation in eczema patients,’ says Dr Justine Hextall, a consultant dermatologist at Tarrant Street Clinic in West Sussex.

Omega 3s: Given its ‘high safety profile, low cost and ease of supplementation, omega 3 [1-3g per day] may benefit patients wishing to improve inflammatory skin conditions [such as eczema] through diet’, according to a 2020 review published in the Journal of Cutaneous Medicine and Surgery.

STRESS AND ANXIETY

Strongest evidence: B vitamins; saffron.

B vitamins: The eight B vitamins can help reduce stress by supporting the production of serotonin and dopamine, which play critical roles in mood and the body’s stress response, says Dr Tom MacLaren, a consultant psychiatrist at Re:Cognition Health in London.

‘Try a supplement that covers all the individual B vitamins and check the label says it contains at least 100 per cent of the RDA.’

Saffron: ‘Saffron extract – from the crocus flower – has been shown in several double-blind randomised trials [the most robust trial type] to ease symptoms of stress, anxiety and low mood with no reported side-effects,’ says Ian Jackson, a clinical pharmacist based in Nottingham.

One of these studies, published in 2016 in The Journal of Complementary and Integrative Medicine, found that taking two 50mg saffron capsules daily for 12 weeks had a significant impact on anxiety and depression.

Check labels for a formulation containing 3.5 per cent crocus extract, with all three active plant ingredients: crocin, picrocrocin and safranal.

P.S. CAN A SUPPLEMENT PREVENT DEMENTIA?

Omega 3s: A dose of at least 2g per day may reduce the risk of Alzheimer’s disease, according to a 2023 research review in the American Journal of Clinical Nutrition. ‘These fatty acids are essential for optimal brain health as they make up part of brain cell membranes and aid communication between the brain cells,’ says Dr Ben Dunkley, a cognitive neuroscientist and chief science officer at MYndspan, a clinic specialising in dementia, in Birmingham.

‘DHA, a key omega 3 fat, is particularly concentrated in the brain, supporting its function and also protecting the neurons [nerve cells] against any inflammation.

‘Additionally, omega 3s may protect memory by boosting the brain’s natural repair mechanisms.’

Look for a supplement with at least 250mg DHA per capsule, as studies show that higher DHA levels specifically are associated with improved cognitive function and better memory.

Multivitamins: A targeted multivitamin could help prevent cognitive decline in people over the age of 65, reported the journal Alzheimer’s & Dementia in 2022.

A three-year study found taking a blend of vitamins A, B, C, D, E and K, plus zinc, selenium and magnesium, daily slowed brain ageing by 60 per cent and improved memory and focus, reducing brain age by two years (possibly because older people have a reduced ability to absorb nutrients from food).

…OR HELP YOU LOSE WEIGHT?

The natural weight-loss supplements market is ever-growing, but are the likes of green teas, raspberry ketones and apple cider vinegar any good?

‘In 2021, a US review of 315 trials of weight-loss supplements, published in the journal Obesity, found that not only did they not result in dramatic weight loss but that it was rare that people taking them lost any weight at all,’ says Guildford-based dietitian Clare Thornton-Wood.

So don’t waste your money on diet pills.

Why you'd have to eat 240 eggs to get highest dose of vitamin D... But do you really need that much anyway?

Some supplements contain very high doses it would be virtually impossible to get from eating. But do we need that much? Aidan Goggins, a pharmacist and nutritional medicine director at longevity clinic the Kyros Project, considers the evidence.

Vitamin C

Highest dose sold: 1,000mg.

Food equivalent: 12 oranges plus six kiwis.

For adults, the recommended daily allowance (RDA) is 40mg (a medium orange). Research shows 200mg is the optimum level for immune support. Some evidence shows that doses over 500mg can actually act as a ‘pro-oxidant’ rather than an antioxidant, meaning they generate free radicals (rogue molecules that damage cells) instead of neutralising them.

Omega 3s

Highest dose sold: 2,000mg.

Food equivalent: 100g tinned sardines plus a portion of salmon.

Standard pills have 1,000mg fish oil – the same as a 100g tin of sardines, but would you eat that every day? While there’s no official RDA in the UK, the American Heart Association advises 500mg a day generally, and 1g for those with heart disease. This is half the level in the highest dose products you can buy.

Magnesium

Highest dose sold: 500mg.

Food equivalent: 2 handfuls pumpkin seeds, 100g kidney beans and 75g dark chocolate.

Around 50 per cent of us are low in this mineral that’s vital for healthy bones, muscles and heart. The total RDA is 300mg (100g pumpkin seeds), but research has found 200mg is the best-tolerated pill dose to supplement your diet. Higher doses can cause diarrhoea and lower calcium levels.

Iron

Highest dose sold: 100mg.

Food equivalent: 15 x 8oz steaks.

The RDA is 8.7mg (found in 350g red meat – a steak the size of a deck of cards), but women having periods need 14.8mg. It is better absorbed from food such as red meat (25-30 per cent absorption rate) than from supplements. High doses can cause constipation and vomiting.

Calcium

Highest dose sold: 1,200mg.

Food equivalent: 800ml milk (around four glasses), plus 200g yoghurt.

The RDA for strong bones and teeth is 700mg (equivalent to 2.5 glasses of milk) and most people should be able to get this get from their diet. Those at high risk from osteoporosis should consider a supplement, but high doses over long periods can lead to magnesium deficiency and calcium build-up in your arteries, increasing your risk of heart disease.

Vitamin D

Highest dose sold: 10,000 IU.

Food equivalent: 240 eggs.

It’s almost impossible to get enough vitamin D from diet alone as most is made by sunlight on skin. The NHS recommends taking 10mcg (400 IU) in winter, based on the minimum requirement for bone health. It suggests 25mcg (1,000 IU) if you’ve been diagnosed as deficient. Long-term doses over 10,000 IU have been linked to elevated calcium, which can cause kidney damage.

Folic acid

Highest dose sold: 800mcg.

Food equivalent: 3 cups of cooked lentils 600g).

This B vitamin – found in leafy green veg, beans and lentils – has an RDA of 200mcg which is achievable from diet (1.5 cups of cooked lentils). Supplements are strongly recommended for women trying for a baby or those who are pregnant, to prevent birth defects. Taking doses over 1,000mcg long-term can mask vitamin B12 deficiency and cause liver toxicity.

Zinc

Highest dose sold: 22mg.

Food equivalent: 4 raw oysters.

The RDA is 7-9.5mg per day (around 150g of minced beef) and you should be able to get this from your diet, as it’s found in meat, seafood, grains and dairy. High-dose supplements are sometimes recommended to reduce the duration of a cold along with vitamin C – although research is mixed. It can cause stomach upsets at higher doses (above 40mg) and compete with copper in the body.

Turmeric (curcumin)

Highest dose sold: 1,000mg.

Food equivalent: 15 curries.

Studies show that curcumin – the yellow pigment in turmeric – is anti-inflammatory and may help joint pain at doses from 500 mg-1g daily. One teaspoon (about the amount per curry) contains around 70mg curcumin.

HOW YOUR MEDICINE CAN DRAIN YOUR BODY OF NUTRIENTS

Did you know that some medications can also block important vitamins and minerals? In the short-term these effects are likely to be mild, but if you’re taking medication for years it can become a more serious problem. If you are on any of the drugs below, you should have regular blood tests to check for deficiencies, says pharmaceutics expert Professor Simon Gaisford.

WEIGHT-LOSS DRUGS: Can affect vitamin B12 and zinc. Research has found that long-term use of Ozempic and other GLP-1 receptor agonists used to treat obesity and type 2 diabetes could lead to deficiencies, particularly in vitamin B12 and zinc. These drugs appear to interfere with the absorption of these nutrients. This is because they work partly by slowing the rate the stomach empties at, which can lead to delayed breakdown of nutrients, so they may just pass out as waste. Plus, the drugs make the stomach less acidic, so some nutrients can’t be fully broken down and absorbed.

HEARTBURN PILLS: Can affect iron, calcium, magnesium, vitamins B12 and C. Proton pump inhibitors (PPIs) such as omeprazole are taken by millions to treat heartburn and to prevent stomach ulcers in patients on other medications. They work by reducing stomach acid production, but iron, calcium, magnesium and vitamins B12 and C all need an acidic environment to be fully absorbed. Nutrient deficiencies are a problem, particularly for older people who suffer from reduced nutrient absorption anyway.

STATINS: Can affect coenzyme Q10. Statins block the release of this compound in the body needed for energy production, particularly in the muscles. This can lead to leg cramps.

STEROIDS: Can affect calcium and vitamin D. Steroids are anti-inflammatory drugs prescribed for many conditions including asthma. They have a major effect on how well calcium and vitamin D are absorbed in the gut, which can lead to bone thinning. NHS guidelines suggest those taking steroids for more than three months could benefit from taking calcium (700mg a day) and vitamin D (10mcg).

DIABETES PILLS: Can affect vitamin B12. Metformin is taken by around three million people in the UK with type 2 diabetes. But studies – including a large 2014 review published in the journal PLOS One – have found it can deplete levels of vitamin B12, needed for energy, a healthy brain and nervous system, and red blood cell formation.

TIMING IS EVERYTHING WHEN TAKING THE PILLS 

 If you always take your supplements with a swig of tea first thing, you might not be getting the most out of them. Different nutrients need different conditions to maximise their absorption.

Pharmaceutics expert Professor Simon Gaisford advises on how to take your pills so they work best...

VITAMIN C

When? Before breakfast.

Most water-soluble vitamins are best on an empty stomach, as absorption can be hindered by proteins and fibre in food. You can buy 1,000mg doses of vitamin C, but 400mg is what we can absorb: excess is peed out.

IRON

When? First thing, with orange juice.

Take on an empty stomach as certain foods – like tea – block iron. Vitamin C aids absorption.

FISH OILS

When? Post-breakfast.

Don’t take fish oil capsules – i.e. omega 3 – before you’ve eaten, as they need dietary fat to help their absorption. Avoid them before a workout or bed: digesting them can cause acid reflux.

CALCIUM

When? With breakfast.

Calcium is often combined with magnesium, but the two can compete for gut absorption. Try a 2:1 ratio of calcium to magnesium.

PROBIOTICS

When? 30 minutes before food.

Probiotics are live bacteria which must reach the gut intact, so avoid taking them with anything that might destroy the bugs, such as hot drinks, acidic juice or alcohol.

MULTIVITAMINS

When? With a meal and water.

A fat-containing meal will ensure fat-soluble vitamins, such as A or D, are absorbed. Take with a drink to help absorb the water-soluble vitamins – though what you’ve eaten might still impair some of the nutrients. Consider separate water and fat-soluble vitamins rather than a multivitamin.

VITAMIN D

When? With meal that includes fat.

Taking it with food ensures the optimal release of bile and pancreatic enzymes needed to absorb this fat-soluble vitamin. But ensure the meal has fat (e.g. nuts).

MAGNESIUM

When? One hour before bed.

Magnesium has a relaxing effect so it makes sense to take it at bedtime. Or try a magnesium cream: a 2017 study from Hertfordshire University found applying this for two weeks improved blood levels of the mineral by more than double compared with a pill.

...WASH them DOWN WITH

Water: Fluid is important for the dissolution of water-soluble nutrients and probiotics.

Skip coffee: Caffeine can reduce absorption –and, as a diuretic, could mean you excrete water-soluble vitamins before you absorb them.

Watch out for tea: The absorption of minerals including iron, zinc and calcium is reduced by black tea as the tannins (plant chemicals) in it bind with them.

SHOULD YOU SPLASH OUT ON THE NEW 'WONDER' SUPPLEMENTS? 

Every few months there seems to be a new ‘wonder’ supplement to revolutionise your health. Here the experts give their thumbs up or down on the latest.

NMN

Nicotinamide mononucleotide (NMN) is a precursor to NAD+, a compound in our bodies that regulates metabolism and plays a role in DNA repair and the immune system. Levels decline as we get older, and are associated with premature ageing, age-related diseases and cancer.

In a recent study by Harvard University in the US, mice fed large amounts of NMN at middle-age had less belly fat. However, this only translated into a 10 per cent lifespan increase for the female mice, explains Dr David Clancy, a biogerontologist who researches ageing at Lancaster University.

‘Plus NMN contains nicotinamide, a B vitamin – excess intakes have been associated with an elevated risk of heart attack and stroke, so I’d avoid until there’s stronger evidence.’

BIOTIN

Also known as vitamin B7, it’s important for healthy hair, skin and nails and has become a key ingredient in many hair-growth supplements. But experts aren’t convinced.

‘A true biotin deficiency can result in brain and muscle dysfunction, hair loss and dry skin – however, this is incredibly rare and a condition you’re born with,’ says Dr Sophie Momen, a consultant dermatologist at Cadogan Clinic in London.

‘There’s no evidence that biotin supplements have any benefit to help hair growth in healthy individuals,’ she adds, warning that research shows the supplements can skew the results of thyroid function tests and heart attack markers.

LION’S MANE

Studies show this mushroom may boost immunity, stimulate nerve growth in the brain and even help those with early dementia.

A 2021 study by Chung Shan Medical University in Taiwan found it improved cognitive test scores in people with early Alzheimer’s (taking a 350mg daily supplement).

Animal studies also suggest lion’s mane may improve memory and recall in people who don’t have dementia.

RESVERATROL

THIS is found in the skin of foods such as grapes and blueberries. ‘In test-tube studies resveratrol has been shown to have anti-inflammatory and antioxidant properties that could, in theory, protect cells from damage which contribute to ageing,’ says David Clancy.

‘But animal studies haven’t yet shown enough evidence for a robust anti-ageing effect that could be repeated in humans.’

CREATINE

Associated with body-builders, creatine has benefits beyond muscle health and could help with menopause symptoms such as brain fog, as well as depression, according to new research. This naturally occurring compound replenishes adenosine triphosphate (ATP), the body’s primary energy-carrying molecule.

‘Creatine fuels all cells with high energy demands, including those in the brain and our immune cells,’ says Professor Jenna Macciochi, an immunologist at Sussex University. ‘Emerging evidence suggests it may support cognitive functions such as memory and focus, especially during periods of stress or after a night of poor sleep.’

ELECTROLYTES

Electrolyte powders that you dissolve into water to boost hydration are just tastier, more expensive forms of the rehydration sachets which are recommended after a bout of diarrhoea. ‘Electrolytes are just common minerals key to keeping the body well-hydrated, ensuring water is stored in the cells and not just peed straight out,’ explains Dr Lindsy Kass, a sports and nutrition scientist.

‘But most of us get plenty from a normal diet, so unless you’re actually dehydrated you really don’t need extra.’