Intermittent fasting: benefits, risks and guidelines

Intermittent fasting (IF) has become a widely discussed dietary approach, with several patterns such as alternate‑day fasting, time‑restricted feeding (e.g., 16:8) and periodic fasting. Research links IF to weight loss, reduced inflammation and improved blood‑sugar control, though some studies note modest advantages over daily calorie restriction and highlight potential drawbacks like disordered eating.

Health professionals note that IF may affect thyroid function, advising caution for people with hypothyroidism. Comparisons with calorie counting show IF can produce slightly greater weight loss in some trials, while overall differences are small. A French dietitian, Nicolas Aubineau, explains that IF aims to support organ detoxification and can be used intermittently by athletes for recovery. Scientific evidence is mixed: a 2022 Inserm review found IF no more effective than other diets for weight loss, whereas the Montreal Institute of Cardiology reported significant results in 2024. Experts stress that IF is unsuitable for individuals with eating‑disorder tendencies or certain medical conditions.