METHODS

Data sources:

Medline (1966 to October 2003), CINAHL (1982 to October 2003), EMBASE/Excerpta Medica (1980 to October 2003), Cochrane Library (Issue 3, 2003), AMED (1985 to October 2003), bibliographies of relevant articles, and expert contact.

Study selection and assessment:

randomised controlled trials (RCTs) in any language of ⩾6 months’ duration in which dietary advice was the main intervention in adults aged ⩾18 years with type 2 diabetes. Studies of patients with impaired glucose tolerance, acute illness, or pregnancy or of the effects of medication, fish oils, supplementation, or Chinese medical herbs were excluded. Studies were assessed by 2 independent reviewers for design, allocation concealment, blinding of outcome assessment, …