How stress and poor sleep affect your weight

Stress and poor sleep are two of the most overlooked contributors to weight gain — and they work against you in very similar ways.

When you are stressed, your body releases a hormone called cortisol. Chronically high cortisol levels increase cravings for sugary, salty, and fatty foods, and encourage fat storage, particularly around the waist. A 2024 review published in Clinical Obesity confirmed that long-term exposure to cortisol is increasingly linked to obesity development.*

Poor sleep makes this worse. Research shows that sleeping fewer than seven hours per night raises ghrelin (your hunger hormone) while lowering leptin, the hormone that tells you when you are full.** The result is that you feel hungrier, eat more, and reach for processed foods. It also raises cortisol levels; sustained high levels of cortisol can lead to increased insulin levels, more food cravings and poor sleep, which then becomes a cycle.***

Managing stress and prioritising sleep are not luxuries — they are essential tools for managing your weight.