Which of these is a major trigger for asthma attacks?

Cold weather is indeed a major trigger for asthma attacks. This phenomenon occurs because cold air can lead to airway constriction in individuals with asthma. When the airways are exposed to cold, dry air, they can become inflamed and hyperreactive, resulting in bronchospasm, increased mucus production, and difficulty breathing. It is important for individuals with asthma to take precautions in cold weather, such as wearing a scarf over their mouths to warm the air they breathe.

In contrast, eating protein-rich foods, regular exercise, and sleeping supine do not typically trigger asthma attacks. While some individuals may have specific food sensitivities, protein-rich foods are not broadly recognized as a common asthma trigger. Regular exercise can actually improve lung function for many asthmatics when performed in a controlled environment and can stimulate a beneficial response in the respiratory system, assuming proper precautions are taken. Sleeping supine, or on the back, can influence some individuals with asthma, but it is not a widely acknowledged trigger. As such, cold weather stands out as a significant and relevant trigger for asthma attacks.