A GP who believes that a simple vitamin deficiency is responsible for many illnesses has revealed how he has spent thousands of pounds of his own money treating his patients.

Dr Joseph Chandy, a long-serving family doctor in Horden, County Durham, is convinced that vitamin B12 deficiency is grossly under-diagnosed by UK doctors.

He believes that many people who develop severe symptoms, including paralysis and blindness can be helped by regular vitamin B12 injections.

Vitamin B12, found in meat, eggs and dairy products, is vital in producing red blood cells. A lack can lead to anaemia, resulting in tiredness and poor resistance to infection.

He has struggled to convince the medical establishment that his new approach is valid and has even been threatened with the sack because of his views.

While he now has the backing of County Durham NHS for his unusual approach, he disclosed that because of opposition to his controversial views, he had to fund the treatment of many of his patients.

Yesterday, Dr Chandy held a press conference to present his evidence to the medical world and call on Health Secretary Patricia Hewitt to adopt his method of diagnosing vitamin B12 deficiency.

In the audience at Peterlee Leisure Centre were many of the 750 patients who have benefited from Dr Chandy's approach to medicine.

One after another, they stood up to explain how their symptoms cleared up or dramatically improved after they were treated by Dr Chandy.

One patient, Catharine Iceton, 30, from Peterlee, was diagnosed with multiple sclerosis and increasingly had to rely on a wheelchair because of difficulty walking.

After she was diagnosed as having a vitamin deficiency, Mrs Iceton was given the first in a series of injections by Dr Chandy.

She said: "I noticed the difference that evening."

During the night she got up to use the toilet and realised she could walk unaided.

Another of Dr Chandy's patients, Jeanette Chapman, was in despair because of an illness that led to all her hair falling out.

She was diagnosed as having a vitamin deficiency and soon grew her hair back, which meant she could come off anti-depressants.

Another patients in the audience spoke of regaining sight in one eye after having vitamin injections.

Dr Chandy urged the Department of Health to accept his new diagnostic approach to vitamin deficiency.

He said such an approach could save the NHS millions of pounds by cutting out inappropriate scans and treatments.