The defence of body weight: a physiological basis for weight regain after weight loss
Priya Sumithran
Clinical Science (2013) 124, (231–241)

Full Text Article:  http://www.clinsci.org/cs/124/0231/cs1240231.htm

Although weight loss can usually be achieved through dietary restriction and/or increased physical activity, the overwhelming majority of people regain the weight that they have lost over the long-term. A meta-analysis concluded that 4.5 years after completing a structured weight-loss programme comprising a hypocaloric diet with or without exercise, the average weight loss maintained was 3 kg (representing a 3.2% reduction in initial weight) [1]. The proportion of people who successfully maintain weight loss varies depending on the definition of ‘weight loss maintenance’ from less than 3% (for maintaining 100% of reduced weight at all annual visits for 4–5 years after completion of a weight-loss programme [2]) to 28% (for maintaining a loss of at least 10% of initial body weight at 4 years [3]). Wing and Hill [4] propose defining successful weight loss maintenance as “intentionally losing at least 10% of initial weight and keeping it off for at least 1 year”. According to this definition, 20.6% of 228 overweight people in a random-digit-dial telephone survey in the U.S.A. reported being successful weight-loss maintainers [4]. Why is diet-induced weight loss so difficult to maintain?

The present review, which focuses on data from human studies, begins with an outline of body weight regulation to provide the context for the subsequent discussion of short- and long-term physiological changes which accompany diet-induced weight loss. A number of comprehensive reviews of the topic which have included insights from animal models of obesity have been published elsewhere [5,6].