Many supplements include a safety statement along the lines of “If you are pregnant, nursing, taking any medication or have a medical condition, please consult your healthcare practitioner before taking any dietary supplement”.
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As it is common knowledge that doctors in the UK have little or no nutrition training it is likely that only a very few people with important medical concerns will seek the advice of their practitioner. This “advice” from the manufacturer might be interpreted by some as an attempt to devolve responsibility to the professional with the best indemnity cover but, in the UK, possibly the least knowledge.
It would not be unreasonable for any doctor who is approached by one of their patients with such an enquiry, about which they were not knowledgeable, to admit their ignorance and, following the principle of “first do no harm”, advise their patient to not take the supplement(s) in question. If the manufacturers who make such safety statements on their packaging were serious about the welfare of the consumer and convinced of the benefit of their products then they should be prepared to educate the medical profession as to their risks as well as the benefits.
The medical profession themselves would also do well to get up to speed on the risks as well as the potential benefits of the appropriate use of nutritional supplements. This is particularly important as serious adverse reactions involving nutritional supplements are likely to involve them to no small degree. Often they will not be aware of their patient’s use of nutritional supplements as a recent survey revealed.
Use of over-the-counter, OTC, medicines including food supplements by in-patients at Guy’s Hospital in London was assessed and the results revealed that 64.0% of them had been consuming at least one such preparation prior to admission and that nutritional supplements had been used by 45.6% of them. However the patient’s medical notes only detailed 4.9% of these OTC preparations. Additionally 9.7% of these products were still consumed during hospitalization with only 31% of these being recorded in the notes. At least one potential nutrient-drug interaction came to light as a result of the survey.
The issues of the suitability of nutritional supplements and the presence of commonplace contraindications to their use or possible adverse reactions were not addressed by this paper.
Reference Oborne CA Luzac ML. Over-the-counter medicine use prior to and during hospitalization. Annals of Pharmacotherapy. 2005 Feb;39(2):268-73
In practice it would seem that it is often left to the consumer to inform him/herself as to whether their use of nutritional supplements is both appropriate and safe.