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K E Y P O I N T S

The recommended daily allowance (RDA) refers to the amount of essential nutrients needed to avoid a deficiency.

The report was produced by the Expert Group on Vitamins and Minerals (EVM) and consumer advice was then published by the Food Standards Agency (FSA).

The current intakes of most vitamins and minerals were found to be safe. However, one substance - chromium picolinate - may have the potential to cause cancer and five supplements may cause damage if taken in large quantities over a long period of time.

Safe upper limits (SULs) were recommended for eight supplements and guidelines were given for a further 23.

Responses to the report have been varied - some organisations have welcomed the report, while others are concerned that people could be put off taking supplements altogether.

Experts say a balanced diet should provide healthy individuals with all the nutrients they require, but that some people may need supplements if they're ill, pregnant or have a poor dietary nutrient intake.

Are vitamin and mineral supplements safe?

Bupa investigative news - 20 May 2003
written by Rachel Newcombe, reporter for Bupa's Health Information Team

Vitamin and mineral supplements are widely used, particularly during illness or pregnancy. However the safety of some substances has come under fire, following the publication of an expert group report on dosage levels. But which supplements are affected and what does this mean for consumers?

What were the headlines?

The report was widely covered by the British media, making the news in most publications.

Headlines included, "Vitamin pills could damage health", "Vitamin sales boom sparks fears over excess doses", "Vitamin pill alert will be hard to swallow" and "Too many vitamins could be bad for you". The reports ranged from thorough coverage, to a brief overview of the key points. Some reports gave the impression that taking all supplements may be harmful, an aspect that's since gained criticism from various healthfood organisations.

What is the bigger picture?

The report in question was carried out by the Expert Group on Vitamins and Minerals (EVM) - an independent expert advisory committee. They looked at over 10,000 pieces of evidence regarding harmful effects associated with 31 vitamins and minerals, including a thorough examination of international research.

Safe upper limits (SULs) were suggested for eight supplements, including vitamin B6 (10mg), beta-carotene (7mg) and zinc (25mg), and an additional 23 supplements received guidance levels (there wasn't strong enough evidence to determine a SUL). The report concluded that the majority of vitamins and minerals are safe if the doses taken don't exceed the recommended SUL.

Following publication of the report, the Food Standards Agency (FSA) issued advice saying that five supplements could cause damage if taken in large quantities over a long period of time. These are:

Beta-carotene (a vitamin A precursor) - long-term excessive intake is linked to an increased risk of lung cancer in smokers and those exposed to asbestos.
The FSA advises against taking more than 7mg of beta-carotene a day
Manganese - long-term excessive intake linked to muscle and nerve disorders in older people.
According to the FSA, taking less than 4mg a day is unlikely to cause harm. For older people, the FSA says that 0.5mg a day or less is unlikely to cause harm.
Zinc - may damage the immune system.
The FSA advises against taking more than 25mg of zinc supplements a day.
Niacin (which is found in two forms: nicotinic acid and nicotinamide) - long-term excessive intake linked to cell damage.
According to the FSA, taking 17 mg or less of nicotinic acid supplements a day, or taking 500 mg or less of nicotinamide supplements a day, is unlikely to cause any harm
Phosporous - long-term excessive intake may damage organs and tissue.
According to the FSA, taking less than 250mg a day of phosphorus is unlikely to cause harm.

Vitamin C, calcium and iron - The FSA have also suggested that taking more than 1000mg of vitamin C, over 1500mg of calcium, or more than 17mg of iron per day could lead to abdominal pains and diarrhoea.
If anyone is experiencing such symptoms due to too much vitamin C, calcium or iron, the good news is that these problems will disappear once they stop taking the supplements.

Sir John Krebs, chair of the FSA, said, "While in most cases you can get all the nutrients you need from a balanced diet, many people choose to take supplements. But taking some high-dose supplements over a long period of time could be harmful."

"We are using an extremely thorough independent expert review of the scientific evidence on the safety of vitamins and minerals as the basis for new advice to help consumers make informed choices. In addition, the Board of the FSA will be considering what further action we would wish the supplements industry to take," he added.

“Healthy individuals who eat well - and most people with commonsense are going to do so - will obtain all the nutrients they require from their diet. People who are ill or elderly, and aren't able to eat sufficiently, do benefit from supplements and should continue to use them. It has been shown in animal studies that megadoses of chromium picolinate appear to be linked to an increased risk in cancer. As a general rule, people should try and avoid taking megadoses of any supplement, as it could cause unwanted side-effects. If you do want to take supplements, I would recommend doses of multivitamins and minerals that contain the recommended daily allowance.”

Rhoda Sutherland,
state registered dietician
Bupa Hospitals Southampton

What does this mean?

Reactions to the report were varied, ranging from interest to serious concern about the recommendations.

Sheila Kelly, executive director of the Proprietary Association of Great Britain (PAGB), an organisation representing the manufacturers of vitamins and minerals, said, "The safety of the consumer must be our paramount concern. Companies have worked to established guidelines on safe upper limits on a voluntary basis for many years. In the EVM report, for the majority of vitamins and minerals, the upper safety levels remain the same and most products already comply with the dosing regime recommended."

She added that, "It's important to note that the limits proposed are for products consumed every day. In some cases there is a benefit in taking higher doses on a short-term basis and people should still be able to do so."

Ann Walker, an advisor for the Health Supplements Information Service (HSIS), said, "The most important outcome of these recent reviews that are being conducted on a UK and European-wide basis is that we can give clear, consistent and appropriate advice to the public on the use of vitamins and minerals ... The fact that the majority of the upper levels recommended by the EVM have remained unchanged, or have been relaxed, is testament to the limits already in place and that they are safe and working."

"However," she added, "the EVM has recommended that the safe upper limits (SULs) of some health supplements when used on a daily basis throughout adult life, such as vitamin A and vitamin C, be reduced. In these cases it must be noted that a wealth of safety data accumulated over years of testing already exists for these vitamins and these recommendations are not relevant to short-term use."

James Connell, a nutritionist from Quest Vitamins, said, "It is true that an individual consuming a diet that meets current healthy eating criteria and provides an appropriate amount of energy would be able to meet the recommended daily amounts (RDAs) from diet alone. However, in reality, the pace of modern life often does not allow for the consistent consumption of a balanced diet and the processes involved in the manufacturing, cooking and storing of food can sometimes compromise the nutrient content of the meals we eat."

The Alliance for Natural Health (ANH) was concerned by the report. Dr. Robert Verkerk, executive director of ANH, said, "We regard the FSA's message as both scientifically misinformed and irresponsible, particularly if it has the effect of stopping people supplementing. There are very few cases indeed of vitamin or mineral products causing adverse effects. There is very little evidence that long-term supplementation is harmful, yet there is good evidence that it is beneficial."

He added that, "Their view on chromium picolinate having the potential to cause cancer is highly controversial and based on very limited laboratory evidence. Clinical studies on humans do not support this. The FSA has relied on very limited animal studies with high doses of single nutrients to draw their conclusions that are deeply misleading."

According to the Health Food Manufacturers Association (HFMA), the majority of findings are consistent with the SULs already used by their members, but in some cases the SUL and guidance levels, "differ significantly from those of other internationally recognised bodies". They also believe the report is flawed, "in a number of aspects of the interpretation of the science of safety to the extent that it could lead to unnecessary bans on some key nutrients and unreasonably restrictive levels being imposed on others".

A C T I O N P O I N T S

If you take supplements, stick to within the RDA, unless you've had guidance from a state-registered dietician or clinical nutritionist to exceed the dose.

If you've got questions about dosage levels, consult a state-registered dietician or clinical nutritionist.

Eat a healthy, balanced diet containing fruit and vegetables - this will provide a good range of nutrients.

Most daily multi-vitamin and mineral supplements aren't affected by the guidance.

What does this mean to me?

The good news is that people taking multivitamins shouldn't worry, stressed HSIS. "Daily multivitamins and single nutrient supplements are safe to take," it said in its press release. "Where products are formulated to 100 per cent of the recommended daily allowance (RDA), these levels still fall considerably below the upper safe limits recommended by the EVM for daily use."

Ann Walker believes vitamins can be a great help. "In addition to encouraging a healthy diet in order to achieve good nutritional balance, supplements can play an important role in maintaining health where people are not getting all they need from food alone," she explained.

A spokesperson for the British Nutrition Foundation agreed. "Although eating a varied and balanced diet, in particular one which is rich in fruit and vegetables, will provide all the vitamins and minerals required for most healthy individuals, some people can benefit from supplements at certain times, particularly when there's an increased need for certain nutrients (such as during pregnancy) or when there's likely to be an inadequate dietary intake."

"People should continue taking their supplements as per usual," added Dr. Verkerk from the Alliance for Natural Health. "Given the large body of research that shows that many population groups are deficient in particular nutrients, supplementation is a very valuable accompaniment to a good diet."

Summary

Because some supplements may cause side-effects, it's advisable to stick to the recommended daily amounts (RDAs), unless advised otherwise by a qualified practitioner.