These include diet, light, exercise, drugs, and social interactions. Adjusting these time cues before and during travel can diminish the effects of jet lag and help the body reset its internal time clock to function in a new time zone. Starch and sweet foods high in carbohydrates can cause sleepiness. High protein foods tend to make one more alert. Bright light signals the body to be active while darkness signals that it is time for rest.
Physical exercise stimulates the body and makes it more alert.
Depending on the drug, medicines can alter the biological clock significantly. If you take prescription drugs regularly, be sure to discuss a proper medication schedule during the Travel Planning Appointment. Conversation with others tends to be stimulatory and results in being more alert. Begin preparing for long distance travel three days before departure. Consume more calories than normal.