J Health Behav Med Hist 2026-8.
Debate 1: Does the behavioural systems perspective underestimate biology?
Robert C. van de Graaf, Performance Medicine Specialist, Director
MEDTCC Institute for Health, Behaviour, Medicine and its History, and Perform Health Clinic ,The Netherlands
One question raised by readers of the theory of the article Reframing obesity: from adipose tissue disease to behavioural system outcome [1] concerns whether emphasising behavioural dynamics risks underestimating the biological determinants of obesity.
Contemporary research clearly demonstrates that body weight regulation is influenced by complex neuroendocrine mechanisms. Hormones such as leptin, ghrelin, insulin, and cortisol play important roles in regulating hunger, satiety, energy expenditure, and metabolic balance. Genetic variation may also affect appetite regulation, reward sensitivity to food, and metabolic efficiency.
From this perspective, behaviour may appear to be merely the outward manifestation of underlying biological processes.
However, the behavioural systems perspective does not deny these biological mechanisms. Rather, it seeks to clarify how biological signals influence long-term energy balance.
Within this framework, biological processes shape internal regulatory states within the organism. Signals related to hunger, satiety, fatigue, reward sensitivity, and stress influence how individuals experience and regulate eating behaviour, physical activity, sleep, and other health-related behaviours.
Biology therefore remains central to the explanation of obesity. Its influence on body weight, however, is typically expressed through behavioural regulation unfolding over time.
Rather than opposing biological explanations, the behavioural systems perspective aims to connect biological mechanisms with behavioural dynamics within a single integrative framework.
- Van de Graaf RC, Van de Graaf PF. Reframing obesity: from adipose tissue disease to behavioural system outcome. J Health Behav Med Hist 2026-6.