The "cortisol face" trend has become popular on social media platforms like TikTok, with users linking facial puffiness, water retention, and weight gain to high levels of the stress hormone cortisol. While this idea has sparked widespread discussion online, health experts warn that the information is often oversimplified or exaggerated. Cortisol is a hormone produced by the adrenal glands in response to stress, whether physical, psychological, or emotional. Its role is to help the body cope with stress by releasing stored glucose, raising blood pressure, and increasing alertness. Dr. Michèle Marchaland, a nutritionist, explains that while high cortisol levels can contribute to weight gain over time, the puffy face associated with cortisol excess is usually seen in more severe and long-term conditions, such as Cushing’s syndrome, not from everyday stress. Similarly, diabetologist Boris Hansel points out that you can’t reliably determine if someone has high cortisol levels just by looking at their face in the morning. These symptoms are more nuanced and require medical testing to confirm. Cortisol levels can be affected by several lifestyle factors, including lack of sleep, poor sleep quality, prolonged fasting, excessive exercise, high caffeine intake, and chronic inflammation. Experts recommend maintaining balanced cortisol levels through good sleep habits, effective stress management, moderate physical activity, and a diet that aligns with the body's natural circadian rhythm. While some aspects of the "cortisol face" trend are based on real health concerns—such as the impact of diets high in refined sugars, processed foods, or excessive alcohol on inflammation and stress—many online claims exaggerate these effects to market specific diets or "miracle" solutions. Health professionals emphasize that a single cortisol spike or blood sugar increase is unlikely to cause sudden weight gain in someone with an otherwise healthy lifestyle.