The Memorial Sloan-Kettering Cancer Center lists "Contreras Therapy" alongside others which "show no evidence of efficacy".[42] Gerson therapy – a predominantly diet regime, generally based on: limiting salt, protein and other foods; ingesting large quantities of fruit and vegetables through juicing; augmenting the intake of potassium and iodine; and the use of coffee enemas. According to Cancer Research UK, "available scientific evidence does not support any claims that Gerson therapy can treat cancer [...] Gerson therapy can be very harmful to your health."[43] Gonzalez protocol – a treatment regime devised by Nicholas Gonzalez (1947–2015) based on Gerson therapy.