Note: This advice is given by the CAP Executive about non-broadcast advertising. It does not constitute legal advice. It does not bind CAP, CAP advisory panels or the Advertising Standards Authority.
Marketers should hold relevant substantiation for claims capable of objective assessment. If those claims relate to health-related products or devices, that evidence will usually need to include robust trials conducted on people (Rules 3.7, 12.1 See also ‘Substantiation for Health, Beauty and Slimming Claims’).
Both the ASA and CAP have seen marketing communications for various devices and screening methods that claim to identify food intolerances or allergies and sensitivities. The products have ranged from blood tests to a pen-like probe applied to acupressure points and a device that apparently measured and replicated the body’s electro-magnetic oscillations. Marketers often claim that by identifying certain foods and eliminating them from the diet consumers can avoid the many medical conditions associated with food intolerances. Some marketers have claimed that the benefits include freedom from memory lapses, migraine, eczema, nausea, dermatitis, joint pains, chronic fatigue and irritable bowel syndrome. Also, they list weight loss as a second-hand result of food elimination. Needless to say, in addition to proving the efficacy of the product they advertise, marketers would need to avoid offering treatments for serious medical conditions (Rule 12.2). Marketers of a test or other product should take care not to over-claim or imply usefulness in clinical situations for which it has not been established.
This is a brief summary of the main food allergy tests and devices CAP and the ASA have come across. Marketers should ensure they hold convincing evidence for their products before they advertise:
IgE Testing: The test is well-established and backed by a vast body of scientific literature. CAP has not seen ads for an IgE test but understands that it is the most robust laboratory test for identifying allergens causing symptoms of so-called immediate-type hypersensitivity (also known as Type I hypersensitivity). The results, however, should not be interpreted uncritically: some results will be false negatives (the test indicates the individual can tolerate substances that he or she is genuinely allergic to) and some will be false positives (the test suggests individuals should avoid substances that he or she can tolerate). Marketers should not claim that they can “clinically validate” test results with design certificates or that IgE can function as a sole diagnostic tool (Yorktest Laboratories, 24 October 2007).
IgG Testing: Although it could conceivably work, consistent evidence that it is accurate or useful is lacking. CAP understands that good-quality clinical studies are needed to prove the efficacy of IgG tests.
Electrodermal Testing (most commonly known as the Vega test): The test claims to measure changes in skin resistance and skin conductivity when alleged allergens are placed in a metal plate in the measuring device to which the patient is connected. The substances being tested are sealed in glass vials and are in direct contact with neither the machine nor the patient. Several published double-blind studies have concluded that the test was useless in diagnosing respiratory allergy and sensitisation to common aero-allergens.
In short, neither CAP nor the ASA has yet seen convincing evidence that food allergy or intolerance testing kits can effectively identify food allergies, sensitivities or intolerances or the claimed effects of such allergies (Allergycare t/a Natural Path Group, June 1997; Body Check Health, February 1999; Allergy Testing Service, May 1999; Goldshield Healthcare Direct, May 2000; Mrs Cora Denton, January 2001; 12 September 2001 and Premier Health, 16 October 2002.)
See ‘Ailments, Treatments and Therapies: Kinesiology’.
Last modified : 26 July 2010