Mix pills at your peril, says doctor

By LIBBY MIDDLEBROOK

Health experts believe poorly informed retailers are putting people's health at risk by selling the wrong nutritional supplements.

Otago University lecturer Dr Nerida Smith said many retailers did not know nearly enough about the dangers of combining natural remedies and supplements with conventional medicines.

Her claims follow a New Zealand Medical Journal study published this month that questioned the benefit of supplements such as vitamins, minerals and sports formulations.

Ron Law, executive director of the National Nutritional Food Association, replied that there were "zero deaths" from dietary supplements compared with about 1500 from properly used medical drugs.

However, Dr Smith, a lecturer in pharmacy practice, said that every year a few New Zealanders died through misusing natural medicines.

"I would be very surprised if someone in a health food shop could adequately explain the dangers of St John's wort. It's very much buyer beware."

She said natural remedies such as St John's wort, said to treat depression, had nasty side-effects when combined with other drugs.

Prozac and St John's wort together could cause a fatal buildup of serotonin in the brain.

Nutrition Foundation scientific director Cliff Tasman-Jones agreed that consumers were not being given enough information about supplements.

"From what I see very few people are given instruction that is credible at all," said Dr Tasman-Jones, who is a both a hepatologist and a gastroenterologist.

"The other big concern for me is that many people taking them are taking too larger dosages that they simply don't need and which could be causing toxic effects."

New Zealanders spend more than $100 million a year on nutritional supplements, ranging in price from $5 to $30 a container.

Some of the most popular supplements include vitamin B, for energy assistance, and vitamin C and echinacea, both for the relief of cold and flu symptoms.

Multi-vitamins for everyday nutritional benefits and evening primrose oil for premenstrual symptoms are also big sellers.

Increased distrust of synthetic medicines is thought to have encouraged the use of supplements, although Dr Smith said many were not completely safe when used with other medicines.

Vitamin C could weaken the effectiveness of the contraceptive pill, while various food supplements could alter absorption of important asthma-related drugs.

Pregnant women taking ginger supplements could experience problems and ginkgo combined with warfarin therapy, a blood-thinning process, could cause internal bleeding.

"There's a general belief out there because they're natural that they must be safe. That's certainly not the case," said Dr Smith.

Supplement manufacturers contacted by the Herald say they do as much as possible to ensure retailers are educated about possible side-effects.

Nutra-Life, whose New Zealand division generates turnover of $24 million a year, runs seminars and produces hundreds of manuals to educate retailers.

"We put a heck of a lot into it," said Nutra-Life chief executive Mark Mathews.

Blackmores New Zealand general manager Alison Quesnel said the 60-year-old company put more than 800 people through training courses last year and regularly ran seminars to ensure retailers had fresh information.

Thompsons marketing manager Adam Baker said the company refused to sell products in supermarkets because no one was available to advise customers.

Vita Health Foods managing director Bert Macartney said all staff were given informal training, but he was concerned about the level of overall industry education.

Vita Heath has six retail health food stores in Auckland.

"It's really more like what pharmacies used to be like 100 years ago, when a chemist learned from his master on the job."

Meanwhile, Pharmacy Guild president Gray Maingay said consumers could protect themselves by consulting a doctor or pharmacist and by choosing products made by a reputable company.