The Food-Insecurity Obesity Paradox: A Resource Scarcity Hypothesis

The USDA defines low food security as “reports of reduced quality, variety, or desirability of diet. Little or no indication of reduced food intake.”

Two hypotheses explaining the relationship between obesity and low food security currently dominate the literature. One prevalent hypothesis is that low food secure populations consume high calorie food. The other is that low food secure populations have limited knowledge, time, and resources, to devote to exercise and healthy eating.

Rejecting these hypotheses as simply descriptive, authors of a recent article set out to determine the how and why behind populations experiencing low food security and weight gain. They were determined to understand what aspect of low food security caused a “net, chronic shift in the homeostatic regulation of energy balance.” The authors proposed the “Resource Scarcity Hypothesis,” which draws from the fields of ecology, evolutionary biology, and obesity.

The authors first looked at the role of social status — research suggested that low social status humans and animals might be more metabolically efficient. They also noted that social rank influences energy intake with subordinate animals consuming more energy.

Furthermore, the authors reviewed the connection between an unpredictable food supply and body fat stores and body weight. “These findings suggest that increased energy intake may be a fundamental response to threats to food security that is persistent independent of the actual food supply, in low social status humans.”

The authors found it crucial to examine the role of cortisol metabolism in low social status individuals, since higher basal cortisol levels, lack of cortisol habituation, and lower cortisol reactivity to acute stress are all associated with low social status. Cortisol levels that are chronically elevated may influence fat metabolism and food intake.

In light of the research, the authors recommended examining how enabling individuals to gain control over access to their own food supply using tools like gardening, financial planning, and dietary interventions focused on strategic buying might affect food insecurity.