Review
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Oct 15, 2017; 8(10): 440-454
Published online Oct 15, 2017. doi: 10.4239/wjd.v8.i10.440
Assessing the evidence for weight loss strategies in people with and without type 2 diabetes
Peter Clifton
Peter Clifton, Division of Health Sciences, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia
Author contributions: Clifton P solely contributed to this manuscript.
Conflict-of-interest statement: No potential conflicts of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Peter Clifton, MD, PhD, Division of Health Sciences, School of Pharmacy and Medical Sciences, University of South Australia, GPO Box 2471, Adelaide, SA 5001, Australia. peter.clifton@unisa.edu.au
Telephone: +61-4-3197998
Received: January 13, 2017
Peer-review started: January 16, 2017
First decision: February 20, 2017
Revised: August 15, 2017
Accepted: September 1, 2017
Article in press: September 3, 2017
Published online: October 15, 2017
Processing time: 272 Days and 15.2 Hours
Abstract

This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people without type 2 diabetes. This dietary pattern is currently being explored in a large prevention of diabetes intervention. Intermittent energy restriction is useful but no better than daily energy restriction but there needs to be larger and longer term trials performed. There appears to be no evidence that intermittent fasting or intermittent severe energy restriction has a metabolic benefit beyond the weight loss produced and does not spare lean mass compared with daily energy restriction. Meal replacements are useful and can produce weight loss similar to or better than food restriction alone. Very low calorie diets can produce weight loss of 11-16 kg at 12 mo with persistent weight loss of 1-2 kg at 4-6 years with a very wide variation in long term results. Long term medication or meal replacement support can produce more sustained weight loss. In type 2 diabetes very low carbohydrate diets are strongly recommended by some groups but the long term evidence is very limited and no published trial is longer than 12 mo. Although obesity is strongly genetically based the microbiome may play a small role but human evidence is currently very limited.

Keywords: Protein; Glycemic index; Very low calorie diet; Very low carbohydrate diet; Low fat diets; Intermittent energy restriction; Alternate day fasting

Core tip: Very low energy or very low calorie diet (VLCD) may reverse early type 2 diabetes and very low carbohydrate diets may offer a short term advantage in reducing medication use and/or lower HbA1c more than a more conventional diet. Intermittent energy restriction may be helpful in some people but more data is required. Long term weight maintenance after VLCD may be helped by a higher protein lower glycemic index diet but drugs and partial meal replacements are also helpful.