It wasn't in the title, but yesterday was sleep, Part 1 .  That lots of sleep was probably why there was minimal weight gain on a 21-day cruise was a revelation.  Then to do the research showing the role that sleep can play in your regular home life was a pleasant discovery.   If you've kept up with this blog site, my various articles on sleep surely must have already educated you to the  benefits of good sleep : Boosts immune system. Strengthens your heart. Puts you in a better mood. Increases your productivity. Improves memory. Conversely, less than 5 hours of sleep/night negatively affects the above, and literally can endanger your life.  For example, the  AAA Foundation for Traffic Safety  reports that you're twice as likely to get in a car accident if you "only" get 6-7 hours of sleep, versus 8 hours.  Also too, low sleep reduces your attempts at exercise, which, like sleep and good nutrients, is good for your body. People complain that ...