A good wetsuit hood will be very effective at insulating your head and helping to regulate your body temperature in the water. Our blood vessels are closer to the skin on our heads and it won’t take long to start leaching your body heat to the elements, without protection. Even in warm water, prolonged dives or surfing sessions can see you chill down over a period of time, which can detract from your overall enjoyment. Wetsuit hoods also protect against wind chill and can help prevent 'surfers ear'  which you can get from overexposure to the wind and cold water temperatures. If you are a four season watersports enthusiast don’t forget, participating in coldwater sports is 50% attitude and 50% gear. A good hood should always be part of your kit bag.