Restrained and unrestrained eating¹

TLDR

Nisbett's 1972 obesity model predicts that relative deprivation within weight groups leads to within‑group differences in eating behavior. The study classified normal‑weight participants into high‑restraint (hypothetically deprived) and low‑restraint groups, treating restraint as a key behavioral mechanism influencing physiological hunger. High‑restraint participants increased intake with larger preloads, whereas low‑restraint participants ate less as preload size grew, confirming that relative deprivation—not obesity itself—drives individual eating differences.

Abstract

Nisbett's (1972) model of obesity implies that individual differences in relative deprivation (relative to set-point weight) within obese and normal weight groups should produce corresponding within-group differences in eating behavior. Normal weight subjects were separated into hypothetically deprived (high restraint) and non-deprived (low restraint) groups. The expectation that high restraint subjects' intake would vary directly with preload size while low restraint subjects would eat in inverse proportion to preload size, was confirmed. It was concluded that relative deprivation rather than obesity per se may be the cirtical determinant of individual differences in eating behavior. Consideration was given to the concept of "restraint" as an important behavioral mechanism affecting the expression of physiologically-based hungar.