Millions are suffering needlessly from long-term illness because of undiagnosed food sensitivities, a York laboratory has claimed.

The York Nutritional Laboratory, which tests blood samples from patients to detect delayed food allergies, has surveyed 1,761 of its patients over the last 18 months.

And seven out of ten reported a significant improvement to their health as a result of excluding food from their diet to which they were sensitive.

Lab director John Graham says the patients had an average 12-year history of chronic conditions, such as migraine, irritable bowel syndrome, eczema, asthma, arthritis and psoriasis, that mainstream medicine had failed to cure. He said 672 patients had suffered symptoms for more than 20 years.

"Indeed, many of the patients reported having had the illnesses all their lives, and they then went on to find relief within weeks.

"It became increasingly evident that people came to us as a last resort, and yet they could have got better so much earlier in their lives."

Patricia Lewis, of Stockton-on-the-Forest, claims her life has been transformed by changing her diet after getting tested by the lab. "My husband, David, said I was unbearable to live with. Now he thinks I'm the best thing since sliced bread," she said.

Mrs Lewis said she had felt unwell, lethargic, irritable and overweight for many years. "It really did blight my life. I thought I had bowel cancer."

She then read in the Evening Press about a student who had benefited from being tested for food sensitivities by the lab, which is holder of the title Evening Press Business Venture of the Year.

She sent a pin-prick blood sample to the lab, where tests showed she was sensitive to a range of foods, including dairy products, eggs, almonds, blackcurrants, sugar, wheat and cocoa. She says she had to transform her diet but was rewarded by a transformed life. "I feel so much better. I have boundless energy. But if I slip up and eat something I shouldn't, I pay for it the next day!"

Clifford Hirst, of Fulford, said his five-year-old son Marcus' asthma had improved markedly since he had been tested and had subsequently changed his diet, for example by switching to goat's milk from cow's.

Harrogate GP Dr Mike Matthews, who conducted the survey with assistance from York University and has since become medical director of the laboratory, said that on the evidence of the survey, the potential existed to help improve symptoms for millions of people.

"Wider application of the techniques used by York Nutritional Laboratory have the capability both of relieving pressure on busy GPs and local health centres, as well as providing very substantial savings for the NHS as a whole."

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