A naturopath clinic has left a bad taste in the mouth of the Advertising Standards Authority by "misleadingly" claiming it could diagnose food allergies with a blood test.

The authority - in a recently published decision - rebuked the advertisements by Mt Albert's House of Health Nutrition and Herbal Medicine clinic as "unsubstantiated" and lacking "a sound scientific rationale".

However, House of Health director and registered nutritionist Sharon Erdrich, disputed the decision, saying there were overseas studies backing her clinic's claims.

The clinic's adverts had claimed an Immunoglobulin G (IgG) blood test could assess reactions to more than 96 foods.

Advertisement

"We also offer a comprehensive medical blood test that is sent to a laboratory in the United States for IgE and IgG antibodies to at least 96 different foods," the House of Health advertisement stated, according to the ASA decision.

"Research has confirmed a connection between IgG or delayed allergy and inflammatory
bowel conditions such as Irritable Bowel Syndrome. IgG antibodies can be measured to
identify the specific foods implicated."

But the Advertising Standards Authority took aim at the ads, citing peer-reviewed articles by researchers in the Science Based Medicine journal.

"At present, there are no reliable and validated clinical tests for the diagnosis of food
intolerance," the medical journal articles concluded.

They stated that claims promoting IgG testing as being able to diagnose intolerances lacked sound scientific rationale and evidence.

"Further, there is no published clinical evidence to support the use of IgG tests to
determine the need for vitamins or supplements."

The experts said that rather than helping, the use of IgC tests to diagnose food intolerances could instead be harmful by pushing people to unnecessarily avoid certain foods.

For this reason, allergy and immunology organisations worldwide advised against the use of IgG testing for food intolerance, the journals stated.

Advertisement

Despite House of Health's "misleading" advertising claims, the chair of the Advertising Standards Authority chose to take no further action against the clinic.

This was because it had voluntarily withdrawn the ad when made aware an official complaint had been made.

But Erdrich told the Herald she didn't agree with the decision and hadn't been able to attend the ASA's complaint hearing to have her say.

Erdrich, who has a Masters in Health Sciences and is currently undertaking doctoral studies, said she took her advertisement down so it could be "reviewed with links to published research".

She pointed to a series of articles published in overseas journals that highlighted links between "food IcG hyperreactivity" and IcG antibodies and conditions such as irritable bowel syndrome and migraines.