Elixirs of youth or a waste of time? The science surrounding billion pound multi-vitamin industry

Elixirs of youth or a waste of time? The shaky science surrounding billion pound multi-vitamin industry... and why experts think you might not need them at all

It's the age-old conundrum that has never been answered with any conviction, with experts seemingly clueless over whether we should pour a glass of wine with dinner or not.

Yet it's not just sauvignon blanc, merlot and chardonnay that find themselves in the middle of a scientific tug-of- war. 

Over the past few decades, a similar, yet much-quieter debate on multi-vitamins has been building up: are they really worth taking? 

Critics denounce the supplements, which can cost as much as £60 a bottle, as, at best, expensive placebos.

Advocates, however, insist multi-vits bolster immunity and keep energy levels high. Scientists have even claimed popping a daily pill could cut the risk of an array of cancers and help ward off dementia.

The scale of how mad the academic tug-of-war has become was made clear last week, with two conflicting papers published just 24 hours apart.

On one hand, researchers at the Wake Forest University School of Medicine insisted the benefits of multi-vitamins on halting cognitive decline were clear. 

Although 'too early' to recommend supplements as a way of protecting our brain against the natural deterioration which comes with ageing, the three-year study, published in the journal Alzheimer's and Dementia, bragged it was the 'first evidence' of any cognitive benefit among older adults.

But a day later, researchers at the Brigham and Women's Hospital — affiliated to the prestigious Harvard University — warned vitamin D and omega-3 supplements won't save older adults from becoming frail.

Experts say multi-vits are essentially redundant if people eat a balanced healthy diet but the truth is millions of Britons use them in the belief that they help boost their health

How much do you need of each vitamin and mineral per day and where to get them

Vitamin A

What does it do? 

Helps support the immune system, maintain eye and skin health.

How much do you need?

Men need 0.7mg and women 0.6mg per day.

Where can you get it? 

Some foods like cheese, eggs, oily fish and liver contain vitamin A directly.

Others foods like carrots, sweet potatoes and mango contain a substance called beta-carotene which the body can convert to vitamin A.

Vitamin B

What does it do? 

Helps release energy from the food and keeps the nervous system, eyes and skin healthy. 

Folic acid in particular reduces the risk of birth defects as babies develop in the womb.   

How much do you need?

There are many types of vitamin B which the body needs, this includes folic acid. 

People need about 1mg of some, like vitamin B1, and up to 16mg for some, like vitamin B3, daily.

Where can you get them? 

Dairy, eggs, mushrooms, meat and fish, avocado, peanuts, soya beans, oats and bananas dark green vegetables like spinach.

Vitamin C

What does it do?

Helps maintain healthy skin, blood vessels, bones and cartilage and helps with wound healing. 

How much do you need?

Adults need 40mg of vitamin C per day.

Where can you get it?

Citrus fruit like oranges, and vegetables like peppers, broccoli and potatoes 

Vitamin D

What does it do? 

Helps keep bones, teeth and muscles healthy.

How much do you need?

0.01mg per day

Where can you get it? 

Sunlight for most of the year as well as from oily fish, red meat and eggs. 

Vitamin E

What does it do? 

Helps keeps the eyes and skin healthy and maintains the immune system.

Where can you get it? 

Plant-based oils like olive, rapeseed and sunflower oils and nuts and seeds. 

How much do you need?

Men need 4mg and women 3mg per day.

Vitamin K

What does it do? 

Helps the body with blood clotting. 

How much do you need?

An adult needs about 0.001mg per 1kg of body weight per day.

So a 65kg person (about 10st) needs 0.065mg of Vitamin K. 

Where can you get it? 

Green leafy vegetables like broccoli and spinach, cereal grains and vegetable oils.


What does it do? 

Helps keep bones and teeth healthy, regulates muscles and ensures blood clots normally.  

How much do you need?

700mg per day.

Where can you get it? 

Dairy and green leafy vegetables like curly kale and okra.


What does it do? 

Helps create thyroid hormones, which help the metabolic rate, the speed at which chemical reactions take place in the body, healthy

How much do you need?

0.14mg per day. 

Where can you get it? 

Cow's milk, eggs and sea food contain good amounts. 


What does it do? 

Helps make red blood cells which are critical for carrying oxygen around the body.  

How much do you need? 

Men and women over 50 need 8.7mg per day.

Women between the age of 19 to 50 need 14.8mg to compensate for the blood lost during their monthly period.

Where can you get it? 

Liver, red meat, beans and nuts.  

The message from Dr JoAnn Manson, the lead author, was clear: 'The new findings are an important reminder that dietary supplements are not miracle pills or elixirs of youth.'

Although technically different to multi-vitamins because they are often sold as standalone supplements, both nutrients are often incorporated in the pills. 

The consensus is a healthy and balanced diet, incorporating, fruit, vegetables and wholegrains, should provide all the nutrients a person needs, effectively rendering multi-vitamins redundant.

But the inescapable fact is that millions consider them a dietary safety net. A study in 2011 revealed people who believed they were taking a multi-vitamin — but actually were given a placebo — were less motivated to exercise or eat nutritiously.

The worried well, those in good health but overly concerned about becoming ill, have fuelled a multi-billion multi-vitamin industry.  

Covid has only boosted the industry, with people more aware than ever of their health, leading to a surge of internet searches and social media posts about 'immune system boosting'.

Gold-standard trials, the rigorous scientific assessment thrust into the limelight during the pandemic as scientists searched for the most effective treatments and vaccines, often fail to back bold claims about the benefits of multi-vitamins.

The Physicians' Health Study II, which ended in 2007, is considered one of the most important completed to date because it was the first and only major randomised trial into multi-vitamins.

Dr Michael Gaziano and team, of Brigham and Women’s Hospital in Boston, Massachusetts, concluded that, while the likelihood of harm from taking the pills is small, so is the benefit. 

The decade-long study, published in the journal JAMA Express, saw 15,000 male doctors take a multi-vitamin or a placebo every day for more than a decade. 

Results were mixed — there were 'modest' reductions in cancer and cataract rates among participants taking the supplements, but no boost to heart or brain health. 

However, some use this paper to argue that there are benefits — as the doctors taking tablets were eight per cent less likely to have cancer. But, among those that did develop cancer, those taking multi-vitamins didn't appear to have any better chance of surviving. 

Another study, this time an analysis which Johns Hopkins researchers review research including data on 450,000 people.  

It revealed the pills didn't offer any protection against heart disease, cancer, cognitive decline — such as memory loss and slowed-down thinking — or an early death.

Writing in the journal the Annals of Internal Medicine in 2013, Professor Lawrence Appel and colleagues said pills are 'not a shortcut to better health and the prevention of chronic diseases'. 

Other steps people can take to boost their health, such as eating healthily and staying slim, have 'much stronger evidence of benefits', they stated.

'If you follow a healthy diet, you can get all of the vitamins and minerals you need from food,' Professor Appel said.

A separate study, published in the British Medical Journal in 2020, found the benefits of multi-vitamins may be all in the head. Researchers at Harvard Medical School reviewed the health of more than 20,000 people, a quarter of whom reported taking multi-vitamin tablets.

While this group felt that their health was 30 per cent better than non-users, when examined by experts they had no less risk of developing chronic diseases and their overall mental wellbeing was similar. 

The team concluded the expectation that multi-vitamins boost health means people who take them think they are working, and are therefore healthier, even though there was no measurable clinical difference in their health. 

Aidan Goggins, a pharmacist and nutrition expert based in London said: 'Time and time again large scales studies have shown multi-vits to be ineffective for improving health risks including heart disease, cancer, and cognitive decline.'

Many will also 'fall prey' to what is known as the 'licencing effect', according to Mr Goggins, whereby 'believing we are doing something good for our health by taking a supplement we feel justified to indulge ourselves in less healthy lifestyle options'.

And, as with anything, there are potential risks of taking multi-vitamins

Taking too much of some vitamins like Vitamin A and D can damage your bone health and organ health, others like Vitamin E can dangerously interact with blood thinning medications.

They also can provide false hope for people battling conditions like cancer, and encourage people to not undergo treatments that might be more effective. 

Despite a seemingly one-sided debate, some studies have found some benefits. 

One, headed by Professor Laura Baker, a geriatric medicine expert at Wake Forest School of Medicine, saw 2,200 over-65s take either a multi-vitamin, multi-vitamin and cocoa extract supplement, just a cocoa supplement or a placebo every day for three years.

Results showed that for the first two years, those taking the multi-vitamin — with or without the cocoa pill — saw their cognitive decline slow by 60 per cent, the equivalent of two years. 

Although a placebo-controlled trial, the study was considered too small to prove conclusive.

Dr David Field, a nutrition expert at the University of Reading, told MailOnline there is 'reasonably convincing evidence' that multi-vitamins can be beneficial, depending on what they contain, how it is formulated and how it is taken.

However, he noted scientists are yet to figure out the optimal amount of vitamins each person needs due to each individual's metabolic and physical differences — so no multi-vitamin will work equally for everyone.

Although the evidence on multi-vits isn't clear cut, certain nutrient supplements are critical for certain groups.

Folic acid is needed for pregnant women to help prevent serious deformities in newborns, such as spina bifida, while all Britons are recommended to take vitamin D supplement to help shore up their bone health during winter.

For the vast majority of people eating a healthy balanced diet should provide all the vitamins and minerals the body needs to function, making multi-vits essentially redundant. But realistically, this isn't the case for everyone.

Mr Goggins added that, in theory, multi-vitamins 'should be a great idea' as it has long been known that we need the right quantities of vitamins and minerals for peak performance.

He said: 'As a population, we do not get enough of these critical nutrients from our diets.'

A 2020 review of vitamin intake and deficiency in older adults found those in seven Western countries, which did not include the UK, consistently had too little selenium, zinc, magnesium and copper.  

Mr Goggins said: 'Two-thirds of young women don’t get enough iodine and the importance of supplementing folic acid for this group for pregnancy is well established.

'With the UK population being unable to make vitamin D during the winter months, 90 per cent of us fall short of this nutrient.'

Since the John Hopkins researchers wrote their 'sobering editorial' denouncing the use of supplements, labelling them a waste of money, research has 'only enforced' this point of view, Mr Goggins said. 

He blamed the products themselves, calling them 'a whitewashed hotch-potch of nutrients that aren’t based on clinical research'.

Many use cheap forms of vitamins and minerals that the body struggles to absorb, the quantities contained in the tablets are often too high or low and many ingredients counteract each other, Mr Goggins said.

For example, iron hinders the body from absorbing other minerals, such as zinc and calcium — so multi-vitamins with a combination of these will be less effective, he explained. 

He hit out at manufacturers for acting 'duplicitously', with a Which? review in 2019 finding that brands — such as Well Woman Original, Holland & Barrett ABC Plus and Nature's Best Multi-Guard Balance — were 'considerably under-dosed'. 

By law, supplements can contain up to 50 per cent more or 20 per cent less of the vitamin amount stated on the label, and 45 per cent more and 20 per cent less mineral. 

But investigators found some brands fail to meet these standards. 


Should YOU be taking vitamin supplements? Why vegetarians need them all year round, EVERYONE should stock up in winter and they might ease aches for menopausal women

There are thousands of vitamin supplements on the market. Many promote themselves as wonder pills that can cure tiredness, boost your brain and enhance your immune system.

Manufacturers are able to make these claims with very little hard scientific evidence because they qualify as 'food products' rather than medicines — making it difficult for the average person to discern what is true.

A study earlier this year found vitamins and mineral supplements give such little benefit to the vast majority, making them a waste of money for healthy people. Researchers said most people get almost all of the nutrients they need from a healthy and balanced diet. 

However, that doesn't mean they are all snake oil.

For example, there is a wealth of evidence that taking vitamins maintains good health and may even slash your risk of some illnesses. And for people with deficiencies, the supplements can be life changing.

Health chiefs advise everyone to take certain tablets, while some groups need to take vitamins in specific doses and at different points of life — such as during the menopause.

Everyone in the UK is advised to take supplements of the so-called 'sunshine vitamin' daily for half of the year, while vegetarians and vegans may need daily doses of vital minerals missing from their diets.

MailOnline's handy guide sets out what vitamins and minerals you may need and when:


There is fierce debate around vitamin supplements.

Experts disagree on whether a healthy person needs them at all and the correct dosage that is required.

Professor Gunter Kuhnle, an expert in nutrition at the University of Reading, told MailOnline: 'It is generally assumed that a healthy, balanced diet should be enough and there is no need for additional supplements.

'But a considerable number of experts believe that supplements can be used as an "insurance" against deficiencies.'

But he said there are difficulties identifying the correct dosage under this approach, as vitamin recommendations are based on how studies and medical data are interpreted.

For example, the UK recommends that people take 40 micrograms (μg) of vitamin C per day, while the EU advises 80μg and the US health chiefs say 90μg. 

'That is due to the way different panels interpret the evidence of what is required by individuals,' Professor Kuhnle said.

Meanwhile, vitamin intake recommendations are 'usually based on the prevention of deficiency' — rather than maintaining good health.

He said: 'That means that if one meets the recommendations, one is unlikely to experience deficiency syndromes, but it is not the amount needed for "optimum health".   

'The reason for this is that it is easy to identify deficiency, but incredibly difficult to identify "optimum health" — although there is increasing interest to move in that direction.'

Professor Kuhnle said supplements are 'important' for those on a restricted diet, such as B vitamins and iron for vegans and vegetarians, as well as folic acid for women planning to become pregnant.

But he added: 'There is of course also the risk of "overdose" — many vitamins can have a detrimental effect when consumed in very large amounts, and there is a risk that this is exceeded with supplements.'

Vitamin D

How much do I need? 10 micrograms per day

Who should take the supplement? Everyone

When should it be taken? October to April

Most Britons get enough of the 'sunshine vitamin' from April to September, as the weather improves and more time is spent outdoors. When the sun hits the skin, it triggers a chemical reaction that creates vitamin D.

But as the days get shorter, the weather gets colder and people cover up when they're outside, Britons need to consume vitamin D in other ways.

The vitamin is essential for regulating calcium and phosphate in the body, which are needed to keep bones, teeth and muscles healthy. Not getting enough raises the risk of rickets (soft bones) in children and bone pain in adults.

Oily fish, red meat and egg yolks are rich sources. But medics say nearly a fifth of adults don't get enough vitamin D and note that it is difficult to consume it in sufficient amounts through food.

Instead, they recommend taking supplements, which cost around 3p per pill. 

While all Britons are told to take vitamin D in the colder months, some groups should take a daily tablet all-year round, including breastfed babies, children aged one to four and those who are not exposed to sunlight — such as those who are bed bound or live in a care home.

All groups are advised to take 10 micrograms of vitamin D. Consistently exceeding this amount can cause too much calcium to build up in the bones, which can damage the heart and kidneys.

The health service last month issued a fresh warning over overdosing on vitamins, after a middle-aged man on a health kick was hospitalised after his kidneys stopped working. 

He was taking 375-times more vitamin D than recommended, along with a too high dose of 19 other over-the-counter supplements.

But a swath of studies suggest set out that those taking the correct dose can reap health benefits. 

Research published in the British Medical Journal earlier this year set out that those who took daily vitamin D supplements were a fifth less likely to suffer from an autoimmune disease, such as arthritis and psoriasis.

And a team at the University of South Australia Cancer Research Institute this month found had sufficient vitamin D levels were less likely to suffer diabetes and heart disease.

However, other studies have found no sign that vitamin D supplements prevent poor health.


How much do I need? 8.7 micrograms per day for adult men and women over 50; 14.8 micrograms for women aged 19 to 50

Who should take the supplement? Women with heavy periods and some vegetarians and vegans

When should it be taken? Daily among those who need them

Iron produces haemoglobin — an essential ingredient in red blood cells, which carry oxygen from the lungs around the body.

Liver, red meat, beans, nuts and dried fruit are good sources and most people get enough iron through their diet.

But those who don't are at risk of developing anaemia, where the body is not producing enough red blood cells to carry oxygen around the body. Breathlessness, feeling tired and a lack of energy are the main symptoms.

Those with heavy periods lose more iron than the average woman, so may need to take a supplement. 

And dozens of studies have shown that there are higher rates of anaemia among those following a plant-based diet, compared to those who eat meat. One showed that a third of vegetarians were iron deficient, compared to no one who ate meat.

Meanwhile, other research has found that three-weeks of iron tablets can slash tiredness by 50 per cent. 

But people should check with their doctor before turning to a supplement.

Dr Duane Mellor, a dietitian at Aston Medical School in Birmingham, told MailOnline: 'Generally, unless someone has been diagnosed with iron deficiency anaemia or has a specific medical condition iron supplements are not generally recommended.'

Those who already get enough of the mineral are at risk of over-dosing. Consuming more than 20μg of iron per day can cause constipation, nausea and can even be fatal. But taking a supplement that has 17μg of iron or less per day is unlikely to cause harm, experts say.

Those advised to take the supplements, which cost around 5p per pill, should take them an hour before eating, as food stops as much from being absorbed in the gut.

Meals should be based on potatoes, bread, rice, pasta or other starchy carbohydrates, ideally wholegrain, according to the NHS

Vitamin B12

How much do I need? 1.5 micrograms per day

Who should take a supplement? Vegetarians and vegans

When should it be taken? Daily among those who need it

Vitamin B12 is essential for making red blood cells, keeping the nervous system healthy and reduces tiredness. 

Meat, fish, milk, cheese and eggs are good sources. So those who eat these animal products should easily get enough — 1.5μg per day — of this vitamin from their diet.

But it is not naturally found in plant-based food, such as fruit, vegetables and grains — although some products are fortified with the vitamin, such as cereal.

Those who don't get enough may suffer from severe tiredness, low energy, breathlessness, feeling faint and headaches.

Dr Mellor said some evidence suggests that those following a plant-based diet should consider taking B12 supplements, which cost 5p per tablet.

He added: 'It is important to note, for most people supplements of other vitamins and minerals are not necessary and it is better to eat a varied diet based on vegetables, fruit and wholegrain with some meat and dairy (or alternatives).'

There's not enough research into the effects of taking high doses of vitamin B12, so it is unclear whether people can have too much.


How much do I need? 700 micrograms per day 

Who should take a supplement? Some oesteoporosis and coeliac disease sufferers, breastfeeding mothers and post-menopausal women — but talk to your doctor first 

When should it be taken? Daily among those who need it

Calcium is vital for healthy bones, teeth and muscles. The body then stores almost all of its calcium supply in the bones, with the rest being spread between the blood, muscle and tissue.

Dairy products, such as milk, yoghurt and cheese, are rich in the mineral. 

Green leafy vegetables, such as kale, products made with fortified flour, including some bread, and fish where the bones are eaten, such as sardines and pilchards, are also good sources of calcium.

As with other vitamins, most adults should get enough calcium from their diet. But those who consistently don't meet the 700μg daily target may be advised to take a supplement, which cost 3p per tablet. 

Studies have shown that calcium supplements can boost bone mineral density and may reduce the risk of risk of fracture. 

Those following a dairy-free diet, have osteoporosis or coeliac disease are most at risk of a calcium deficiency, as are women who are breastfeeding or have gone through menopause, so may be told to take a calcium supplement by their doctor.

Women going through the menopause are also at risk of osteoporosis, caused by lower levels of oestrogen, so may be encouraged to take calcium, as well as vitamin D. 

Not getting enough calcium increases the risk of osteoporosis (weak bones), rickets (soft bones) and breaking a bone from a fall. 

Those who have too much — more than 1,500μg per day — may suffer stomach pain and diarrhoea. But those taking a supplement of 1,500μg or less per day are unlikely to do any harm, experts say.

Folic acid

How much do I need? 200 micrograms per day

Who should take a supplement? Women trying to get pregnant and expectant mothers in the first trimester 

When should it be taken? Between once a day and once a week — depending on doctor recommendations

Also known as folate and vitamin B9, folic acid is a vitamin found in small amounts of a variety of food, including broccoli, leafy green vegetables and chickpeas.

It helps the body make healthy red blood cells and is important to maintain an unborn baby's health — helping its brain, skull and spinal cord develop properly in pregnancy. Studies have shown the vitamin reduces the risk of spina bifida and premature birth.

Women are advised to take a 400 microgram folic acid supplement daily for three months before they begin trying for a baby and during the first three months of pregnancy.  

Folic acid supplements are also used to prevent and treat folate-deficiency anaemia, which can be caused by not eating enough folate-rich foods, drinking too much alcohol, celiac disease, cancer and pregnancy.

Health chiefs say the supplements are safe and taking too much is unlikely to cause any harm. 


How much do I need? 140 micrograms per day

Who should take a supplement? Some vegetarians, vegans and those who do not eat fish

When should it be taken? Daily for those who need it

Iodine helps make thyroid hormones. These keep cells and the metabolic rate — the speed at which chemical reactions take place in the body — healthy.

Milk, eggs and other dairy products, along with fish and shellfish contain plenty iodine. The mineral may also be found in cereals and grains but the amount depends on where the plants are grown.

As with most other minerals, most people should be able to get all the iodine they need from their diet. But those following a strict vegan diet and do not eat fish, eggs or dairy should consider iodine supplements, the NHS says.

Not getting enough can lead the thyroid to increase in size, which will make the neck look swollen. And those with an iodine deficiency during pregnancy may have a child with a low IQ or reading ability. Studies have shown the supplement boost children's brain development.

However, taking too much can change the way the thyroid gland works, which can lead to weight gain.