We all are familiar with the increased fatigue and sleepiness that sometimes settle in after a large meal. Post-prandial means after a meal. With a meal, the body “changes gears” in order to digest the food. It accomplishes this by changes that take place in the nervous system. The body decreases what is called the sympathetic nervous system tone and increases the parasympathetic tone, which results in the shunting of more blood away from the skeletal muscles and towards the digestive tract. The sympathetic nervous system is sometimes thought of as the “fight or flight” side of the nervous system that is involved in more active pursuits. The para-sympathetic nervous system is sometimes remembered as the sleep/feed/breed side of the nervous system and is useful in more relaxed pursuits. It is normal to feel more relaxed or drowsy after a meal because of the increased para-sympathetic tone of the nervous system. However, in Wilson’s Temperature Syndrome sufferers, the post-prandial response can be very inappropriately exaggerated. This may lead Wilson’s Temperature Syndrome sufferers to practically “collapse,” “pass out,” or be “useless” after a meal such as lunch. This exaggerated response has been seen to resolve in many cases with normalization of body temperature patterns with proper T3 therapy.