Mike Lean

Speech Title: Diabetes No More!  Evidence-base weight management and remission of type 2 diabetes: the DiRECT trial

MA, MB, BChir, MD, FRCP (Edinburgh), FRCPS (Glasgow), FRSE
Professor of Human Nutrition, Glasgow University, and consultant physician at Glasgow Royal Infirmary. 
Visiting professor, Universities of Otago and Sydney (to 30/06/2021).

Professor Lean leads ‘broad-focus’ translational, integrative, research and teaching within medical and nutrition training, integrating biomedical research at basic science, clinical and public health levels. Awards include Diabetes UK-Rank Prize Lecturer (2014), Banting Memorial Lecturer (2020/21), Tenovus Medal for Research (2017), elected Fellow of Scotland’s National Academy (FRSE, 2018).

Currently PI on the largest research grant ever awarded by Diabetes UK, the Diabetes Remission Clinical Trial (DiRECT, £2.6m), an NIHR-funded weight loss for long COVID (ReDIRECT, £1.0m), collaborative dietary diabetes remission projects in Nepal and Australia, and pharmaceutical trials.

Published over 600 scientific articles and books, G-Scholar H-Index=114. 

Outside research he makes and plays fiddles, and escapes to climb mountains.


DiRECT (the Diabetes Remission Clinical Trial) has demonstrated reversibility of type 2 diabetes (T2D), identified predictors of remission and led to a new understanding of T2D as part of the metabolic syndrome, driven by excess fat accumulation in ectopic sites, particularly liver. Participants had T2D with <6 years diabetes history, aged 20–65 years, and BMI 27–45 kg/m2, without insulin therapy. Weight loss was induced by ‘Total Diet Replacement’ with 825–853 kcal/day nutritionally-complete formula shakes/soups for 3–5 months. Weight loss maintenance used a conventional food-based diet with 50% energy as carbohydrate. Remissions (HbA1c <48 mmol/mol [<6.5%], without medications) were achieved by 68/149 intervention group participants (46%) at 12 months and by 53/149 (36%) at 24 months. Weight loss >10kg was the strongest determinant of remissions, which were characterized by loss of liver fat and restoration of insulin secretory capacity over 2 years. Remissions were achieved by 82% of those losing >15kg at 2 years. Better quality of life with less anxiety and depression, fewer anti-diabetes medications, lower gamma-glutamyl transferase and triglyceride level were weak baseline predictors. The reversibility of T2D has been confirmed in the DIADEM-1 train in Qatar, using a near-identical protocol, but studies with low-carbohydrate (ketogenic) diets have been less successful. Given the poor prognosis of T2D below age 70, weight loss for remission should be considered a treatment as important as chemotherapy for cancer, targeting >15kg loss, with a major focus on life-long weight loss maintenance.