1. Radiation Exposure Pilots flying at high altitudes are exposed to more cosmic radiation, which may increase long-term cancer risk. 2. Circadian Rhythm Disruption Crossing time zones constantly disrupts sleep cycles, leading to fatigue, hormone imbalance, and even heart health issues. 3. Musculoskeletal Strain ee wh Hours in the same position in a tight cockpit can cause back, neck, and shoulder pain, it's physically demanding in ways people don't expect. 4. Dehydration & Fatigue Dry cabin air