Natural dietary supplements
The internet and email inboxes can be awash with astonishing claims about "natural" dietary supplements promising everything from weight loss to muscle growth and sexual performance.
The reason these ads don’t appear on mainstream media is the claims are very unlikely to stand up to any scientific scrutiny, and may even pose a danger to the health of people taking them.
Some natural dietary supplements will have been through an official approvals process or registration, but buyers should still be cautious.
The medicine regulator MHRA says natural doesn’t always mean safe and that dietary supplements can still have a drug-like effect on the body.
Many natural products can affect your body and have an impact on prescribed medications. It’s important to seek medical advice before taking any supplement.
Any legitimate advert for a supplement has to be backed up with evidence that's been assessed by the European food regulator EFSA.
Additionally, since May 2014, all herbal remedies sold in packs have to be registered with the MHRA's traditional herbal registration (THR) scheme. This doesn’t mean the herbs have been proven to work, but it does confirm traditional use and standards of manufacturing quality.
The MHRA warns that risks of getting fake, substandard, unlicensed or adulterated medicines are greater when buying from illegal online pharmacies. Legitimate UK online pharmacies display the Internet Pharmacy Logo and are registered with the General Pharmaceutical Council (GPhC).
Natural supplement concerns
Here are some examples of "natural supplements" that have prompted medical concern:
- Androstenedione. A steroid precursor that claims to enhance athletic performance and boost testosterone levels. Not only does androstenedione increase the concentration of oestrogen (a female hormone), which can lead to breast development and impotence in men, it may cause abnormal periods, deepening of the voice and increased facial hair in women. Androstenedione has subsequently been banned by several international sports associations, including the International Olympic Committee (IOC).
- Creatine. On the surface, creatine seems safe as it occurs naturally in organs, muscles and fluids of the body. However, creatine sometimes causes side effects, like diarrhoea, cramps and loss of appetite. Weight gain, muscle cramps and loss of kidney function are also associated with taking creatine.
- Ephedra. Was once used in many weight loss products available over the counter. However, when the side effects of using ephedra, which included the increased risk of heart problems and stroke, became apparent, it was banned for use in slimming products in the UK.