👉 Inbreathing is a phenomenon where two individuals of the same species breathe in the same amount of air, often leading to health issues such as asthma and other respiratory problems. It occurs when an individual inhales through their nose or mouth while another individual breathes through a nostril or mouth, which results in the exchange of gases. This can happen spontaneously or by deliberate action, but it is more likely to occur during prolonged exposure to air pollution, smoking, or certain medications that decrease lung function.