Which vitamins really are worth taking?
We’re spending more than ever on supplements. But as experts warn most are a waste of money — and some can even be harmful...
P ill-poppers versus nutrition watchers: the controversy over vitamins and supplements is back with a vengeance.
Britain’s appetite for vitamins and supplements, such as fish oils, has been falling for the past six years, thanks not least to people heeding advice from doctors and dietitians that anyone who eats a balanced diet doesn’t need expensive supplements.
Moreover, a growing body of research has highlighted that some supplements may actually worsen your health.
But vitamins and supplements sales are rising again, with the market growing 1.8per cent in the past year to more than £360 million, according to research last week in The Grocer, the retail industry journal.
Analysts said a combination of guilt over rushed meals, a desire for quick ‘pick-me-ups’ to fuel hurried lifestyles, and the yearning for an ‘elixir of youth’ sparked the revival.
As a result, supermarket sales of health supplements have overtaken those for painkillers for the first time since 2005.
Moreover, the vitamin market may have a new ally. experts from the universities of oxford and surrey warn our diet is dangerously deficient in nutrients that may be causing brain deficiencies in children, as well as problems with immunity and fertility in adults — and even a raised risk of premature death from all causes.
so should we be watching our diets for the right food balance, or could over-the-counter pills offer a properly healthy alternative? THE ONES THAT CAN BE BAD FOR YOU suppleMenTs have taken a severe knock from headline-grabbing research over the past few years. For example, a study in 2011 of nearly 39,000 women aged around 60, published in the journal Archives of internal Medicine, found those who used supplements such as multivitamins and vitamin B6 (the latter for unproven heart benefits) had a greater risk of dying earlier.
Meanwhile, men who took moderate-dose vitamin e supplements (400 international units a day) had a 17 per cent greater risk of developing cancer in the next seven to 12 years, according to a review of evidence presented to the American Association for Cancer research last year.
And women who have high intake (more than 400 micrograms a day) of folic acid supplements increase their risk of breast cancer by 19 per cent, suggested the review. Furthermore, smokers taking high doses of betacarotene had an 18 per cent greater risk of getting lung cancer over five to eight years.
There are several possible explanations — it may be that taking more vitamins than is necessary for healthy cells serves only to feed cancerous cells.
And while antioxidant pills such as vitamin e are marketed to lower our levels of free radicals — substances linked to cell damage, ageing and cancer — it could be that reducing their levels causes more harm than good.
A major review of the evidence suggested our bodies need the stress caused by free radicals to stimulate them to fight infectious disease, reported The international Journal of Biochemistry and Cell Biology — essentially, ‘what doesn’t kill you, makes you stronger’.
The ‘pick-me-up’ promise made for vitamins can backfire, too. research in the Journal of physiology in 2014 shows, for example, that taking vitamin C and e supplements as an energy boost can interfere with the way muscles normally respond to exercise. ‘BEAUTY’ VITAMINS ARE A WASTE OF MONEY iT’s noT just that some supplements have been linked to harm, there are also question marks over the new ‘beauty’ supplements. Vitamin manufacturers have increasingly
tapped into the lucrative beauty market with claims that supplements can hold back signs of ageing.
But European Union analysts say there is no accepted scientific basis for these claims. They should not even be legally allowed on UK packaging or advertising, argues Peter Berry-Ottaway, a food scientist and technical director of the Council for Responsible Nutrition, a body funded by big UK supplement companies.
‘Responsible, reputable companies are sticking to the law, but others simply are not,’ he says.
And supplements can also disrupt our bodies’ vital processes, says Aidan Goggins, a pharmacist and specialist in nutritional medicine. ‘Our bodies are evolved to use nutrients in a balanced and healthy way,’ he says.
‘When you take isolated nutrients in high doses, you can put the system dangerously out of balance. This is because the large dose of one nutrient will effectively block the body’s ability to use other nutrients. It’s like having a football team and only playing 11 strikers or 11 goalkeepers.’ And yet these problems don’t mean that all supplements are over-hyped, useless or dangerous. The situation is far more nuanced. PILLS THAT MAY HELP MEMORY FOR some people, supplements may bring definite preventive health benefits. Vitamin B12, in particular, may help some people stave off the memory problems linked to old age. The nutrient helps keep nerve and blood cells healthy, and helps make DNA.
And low levels throughout life can cause memory loss, according to Gordon Wilcock, an emeritus professor of geratology (the medical study of ageing) at Oxford University.
He explains that at around 70, the lining of some people’s stomachs becomes less capable of absorbing B12 from food, which can lead to chronic insufficiency of the vitamin — and the advent of memory loss.
This means current levels of B12 intake (around 1.5 micrograms) — which even health authorities say are the lower limit of ‘normal’ — may actually be too low in older people, says Professor Wilcock.
One of the advantages of vitamin B12 supplements is that there’s no evidence of a risk of overdosing, whatever your age. ‘Some doctors are giving it to patients, and indeed I have done in the past if they have low B12 and memory problems,’ he says.
For most of us, there’s no need for B12 pills, he says: ‘It’s present in liver, meat and foods such as cereals fortified with it. If you eat a sensible diet, you should get enough.’ OVER 50? THEN CONSIDER THESE HAVING said that, older people with type 2 diabetes or heartburn could consider taking B12, according to Margaret Rayman, a professor of nutritional medicine at the University of Surrey, who has conducted studies in vitamin supplementation.
As she explains, if you’re over 50 and taking metformin (prescribed for type 2 diabetes) or proton-pump inhibitor drugs (used to alleviate symptoms of ulcers and heartburn), the drugs will cut the acidity levels in the stomach.
‘This in turn reduces the levels of hydrochloric acid in the gut lining, which we need to absorb B12. If you’re taking these medicines and not eating foods fortified in B12, then you may well need a supplement.’
She adds that drinking milk can help, as B12 is more easily absorbable in dairy products than meat.
Glucosamine sulfate is another supplement that may help ageing people. It is a natural chemical compound in your body which helps maintain healthy cartilage — the rubbery tissue that cushions joints.
Levels of it drop with age, leading to gradual breakdown of the joint.
Scientists have for years debated whether supplements of glucosamine sulfate help with mild osteoarthritis. In 2005, highly respected research group, the Cochrane Library concluded: ‘People with osteoarthritis who take glucosamine, may reduce their pain, may improve their physical function, and will probably not have side-effects.’ BOOST TEENAGE GIRLS NEED THE NHS recommends children aged six months to five years have vitamin D drops. Vitamin D is needed for healthy bones. It also recommends people over 65 and those who do not get much sun should consider supplementation.
Vitamin D deficiency can cause bone pain and muscle weakness. Low blood levels have also been associated with cognitive impairment in older adults and increased risk of death from cardiovascular disease.
While there is a risk with taking too much, we should all consider taking ten micrograms a day for at least part of the year, according to Professor Rayman. Because we live so far north on the planet, there is quite a lot of deficiency in the UK, she explains.
Don’t overdo it — around 100 times the recommended amount over several months can cause poor appetite, nausea and vomiting.
Professor Rayman also recommends some of us consider taking two other supplements — iodine and selenium. She published research in The Lancet which showed iodine deficiency in pregnancy may damage children’s mental development.
Alarmingly, her study of over 1,000 pregnant women found more than two-thirds were deficient. She recommends pregnant women, and women likely to become pregnant, ensure they get sufficient iodine.
‘Normally, people can get this from milk, dairy and fish, but there is a deficiency danger with teenage girls who consume lots of fizzy drinks and very little dairy.’
Selenium is another vital element that can be lacking in British diets. We have a relatively low intake because there is little of it naturally in the soil on which we grow food.
Deficiency can harm immune systems and fertility in men and women, as well as increasing premature death from all causes, studies show. Professor Rayman says if you eat a lot of fish, you won’t need supplements, but you might if you don’t eat fish, Brazil nuts or meat. THE DANGERS OF OVERDOSING BUT both iodine and selenium supplements carry a real and serious danger of overdosing.
‘People who worry about their vitamin intake often overdo it with supplements,’ says Professor Rayman.
‘With iodine the only commercially available supplements are made from kelp and contain very high levels of iodine, and an excessive intake can actually damage the thyroid gland, causing the types of problem you are originally trying to avoid.’
Too much selenium can lead to selenosis, which can cause hair loss, nausea, fatigue, nerve damage, and even heart attacks and kidney failure.
‘Instead, if you wish to increase your selenium intake, take a combined multivitamin and mineral with low levels of ingredients. For example, with 30-50 micrograms selenium and 140-150 micrograms of iodine.’
Experts agree that taking supplements is not as healthy as getting nutrients from food, which has other health-boosting substances such as fibre. ‘Have a balanced diet,’ says Professor Rayman. ‘If you do that in the UK, you should be fine for all your vitamins, apart perhaps from vitamin D and selenium unless you’re a fish-eater.’