[1] Univ Hosp Girona Dr Josep Trueta, Girona 17007, Spain
[2] CIBER Fisiopatol Obesidad, Girona 17007, Spain
[3] Kings Coll London, London Sch Med, Guys Hosp, Metab Unit, London SE1 9RT, England
[4] Kings Coll London, London Sch Med, Guys Hosp, Dept Diabet Endocrinol & Nutr, London SE1 9RT, England