The judgment ratified by the High Court will be paid by the insurer for Barbara Nash, a "nutritional therapist and life coach," the Daily Mail reported.

Dawn Page, who lives in Oxfordshire with her husband and son, went to Nash looking for a diet that would make her lose weight. Nash told her to drink at least four pints of water a day and to cut down on salt.

When Page complained of vomiting after a few days on the diet, Nash told her that showed it was working and urged her to drink even more water and eat less salt. Within weeks, Page suffered a massive epileptic fit that left her with permanent brain damage.

Her husband, Geoff Page, urged women to be wary of "fad-type diets."

"She was not obese or even mildly obese but, like a lot of women, Dawn liked to look after her weight and was not having much success with the normal ways of doing that," he said.