Sleep. It is an amazing thing. Scientists do not yet fully understand what happens when we sleep, but they do know that is absolutely necessary for life. There are some incredible things that happen when you sleep. Your muscles repair from the work you did (you get fit in your sleep, not when you are working out). Your liver and kidneys detoxify your blood from the chemicals and other toxins you consumed, inhaled or were absorbed through your skin. Your mind makes connections in the brain, wiring novel experiences that you had during the day into memory. Excess fat if burned. Hormones are created, excreted, and balanced, which leads to healthy metabolism, appetite, mood and sex drive. Sleeping is nourishing on so many levels.