Water plays a MAJOR ROLE in weight loss, improved strength AND can help you get the most out of your workouts!   Here are 6 surprising reasons you should be drinking more:   1. Weight loss Skimping out on water can cause water retention and weight gain. Our nutritionist recommends a half cup of water for every hour you're awake. 2. Mood Dehydration affects cognition, concentration and mood. Women tend to experience headaches, fatigue and difficulty concentrating and men tend to experience difficulty with memorization. As the body becomes dehydrated, anxiety and tension increase in both men and women. 3.