Sleep doctors warn of fan-related health risks amid summer heat

Sleep specialists and allergists caution that using a fan overnight can dry the air, irritate the throat and eyes, and stir up dust and allergens. Marie‑Françoise Vecchierini of Hôtel‑Dieu Hospital in Paris advises directing the fan away from the face, adding moisture to the room with a bowl of water or a damp cloth, and avoiding mouth breathing. Allergologist Farid Marmouz, president of the Société française d’allergologie, notes that circulating air can lift pollutants such as paint fumes, aerosol residues and common allergens, worsening respiratory discomfort.

Home‑comfort experts explain that interior design choices also affect indoor temperature. Dark‑painted walls absorb solar radiation throughout the day and release it slowly at night, keeping living rooms warm long after sunset. Thick rugs and thin curtains trap heat, while bulky furniture placed against windows blocks airflow. Simple measures—light‑colored paint, breathable curtains, and rearranging furniture to allow ventilation—can help cool homes more effectively during heat waves.