Sufferers typically focus on consuming just a few types of high-fat or carbohydrate food and can go for years without eating anything else.

Carbohydrate foods trigger the release of insulin, which ids to other ng tryptophan more easily.

They are also ideal carbohydrate foods for helping slightly to boost levels of the 'feel-good' brain transmitter serotonin.

This phase restricts disaccharide-rich carbohydrate foods such as grains, pastas, breads, sugar, potatoes, corn, beans, and legumes.

Subjects also preferred high carbohydrate foods (sweets, salty food and starchy food).