Evidence-based interventions for weight management: where have we been and where are we going?

This seminar will be delivered by Professor James Stubbs at the University of Leeds.

Weight loss and maintenance interventions tend to produce relatively modest effects. Systematic reviews of behavioural/psychological predictors of longer-term weight outcomes find considerable heterogeneity between studies. Many determinants of WLM are established by association rather than longitudinal change scores, using varying theoretical frameworks, different constructs and measures. 

Weight loss invokes quantitatively significant physiological changes on the intake and expenditure side of the energy balance equation that oppose or undermine weight loss. Mathematical models suggest that approximately 25-30% of physiological resistance to weight loss may be due to compensatory changes in energy expenditure, while around 70-75% is due to an increased energy intake (Polidori et al 2016). If this is the case, the majority of physiological resistance to weight loss appears to operate through energy balance behaviours. The empirical measurement of energy balance behaviours over time remains elusive.

In simplistic terms the key challenges for longer-term weight management involve (i) engaging a significant proportion of the population in evidence-based behavioural approaches to weight loss, (ii) adapting behaviour change attempts to navigate around the physiological resistance to weight loss that undermines weight loss maintenance, (iii) providing behavioural solutions to facilitate coping with lapses in the control of energy balance behaviours and relapses in weight and (v) finding methods to scale evidence-based solutions to longer-term weight management across the general population. These challenges are individually considerable and collectively daunting. The behavioural evidence for longer-term weight management is less robust than one might suppose. The quantification of EB behaviours is inexact, making lapses difficult to detect. Several weight management solutions are scaled across the general population, with limited effect and (excluding drugs and surgery) the mechanisms of action remain unclear.

However, the study of weight management tends to fall into large-scale behaviour change interventions and predictors of weight outcomes on the one hand or mechanistic energy balance research on the other. Closing the gap between these two disparate areas of research could be achieved by new innovations in advanced data analytics and quantitative tracking to develop a Behavioral Energy Balance Framework. This may help facilitate objective monitoring of energy balance behaviours during more personalised weight management interventions.