The truth about allergy testingVega testing

This method is sometimes called electrodermal testing, and claims to diagnose food intolerances by measuring changes in your ‘electromagnetic field’ with a galvanometer or computer. Our researchers paid between £60 and £75, depending on where they had the test. 

Electrodermal testing on trial

What we did 

Our researchers visited an independent practitioner and a practitioner from a company called Nutrimark operating from health-food specialist Holland & Barrett. 

The test required researchers to hold a metal probe that was connected to a machine or computer. Another probe was placed on acupressure points on the other hand, creating an electric circuit between them and the machine. 

At Holland & Barrett, vials containing ‘essences’ of different foods were placed in the machine, one at a time, and ‘resistance’ was tested. 

The Vega testing at the private practitioner was computerised and the practitioner tested for different foods through the computer program. 

In both cases, a reduction in current is interpreted as intolerance to that food. 

Our findings

Our researcher Adam was told to avoid four foods by one practitioner and three by the other, with only one overlap. 

Our researcher Dee was told to eliminate or reduce a total of 13 foods by one Vega testing practitioner and 10 by the other, with only one overlap. 

Both researchers were told to avoid wheat in each test, even though neither has a known wheat or gluten intolerance nor any symptoms that would indicate either. The Nutrimark practitioner told both researchers to avoid bananas, cows’ milk and yeast. Dee, who had submitted a food diary before the test, felt that the practitioner ‘pushed the probe harder for certain foods, especially ones I eat frequently and was told to avoid’.

Experts’ verdict

Dietitian Catherine Collins was particularly concerned that the private Vega testing practitioner advised Dee to exclude all grains from her diet. ‘This significantly reduces intake of fibres, selenium and B-vitamins, and would make it difficult to get a balanced diet,’ she said. 

Neither test for either researcher gave matching results for food intolerances. 

Our experts agree that this method cannot be recommended and Dr Morris said: ‘Clinical studies have repeatedly shown Vega testing to be ineffective in diagnosing allergies and intolerances.’