I try to practice what I preach. I probably fly over 100,000 miles a year but I have not missed a single presentation in my career due to illness. I think part of this is luck, but part of this is following the medical research that I present to others. I do not drink alcohol in general on airplanes and when I do drink I keep it moderate (1-2 drinks a day maximum or just a few drinks a week). I never exercise unless I have had 6-8 hours of sleep the night before and I feel awake. I do not smoke or expose myself to smoke (I have to thank my wife for this one because she always moves to a different table at a restaurant or wants to leave if a smoker is nearby). I try to reduce my mental and physical stress by getting some physical activity daily... Finally, I take an Ester-C tablet daily, all year long, because it is gentler on the stomach and because of all the clinical research that supports the use of this product.*