I had this thought come to me awhile ago and do wish now that I had blogged about it then rather than waiting till now (I know I had more in my mind about it at that time which may not have left me... :/.)
I have heard the phrase, "I'll sleep when I'm dead." and while it's marginally funny from a serious perspective it's disturbing. As someone who loves and feels compelled to always be productive I understand this way of thinking. In our society (Western culture, America especially) it is fairly typical to have to get things done to feel of any worth. This fosters a desire and need to be ultra productive or maintain a certain standard that may not be true to oneself or healthy. We work 80 hour weeks (or at least long hours) to maintain the status quo. We have jobs we hate, and demands on our time that far exceed the actual time we have available. A great many people feel the need to meet some grandiose and far off expectation to do everything and be everything to some extent. We have deadlines that loom over us like dark monsters and we ritualistic chide ourselves harshly for not maintaining, even when it's not necessarily what our heart wants.
While this isn't the case for every single person, it's very common, and it's also very sad. The upside is that our bodies know. They know what's right for us, what is enough, and what is too much - if we would but listen...
As is proliferated by The Secret, Wayne Dyer, and a number of other authors and people of various industries who speak on such subject, including the lovely Lissa Rankin of Owning Pink, our bodies constantly tell us what they need, want, and what nourishes them. When you find yourself doing something effortlessly, so much so that time passes without you knowing that's a key right there. Whatever you find joy in, is good for you. (And we mean real live joy, not the "temporary" gratification that can be found is less than good for one practices such as drug use, etc.)
However, even beyond that is the message from our bodies to take care of ourselves. Likes and desires aside there are certain things we all need. In general humans are social creatures, we need to be around and interact with one another. But not just anyone, you need people who feed your soul, who support you, and who are real to and for you. For some this seems like a luxury as it's so easy to find those that do less for us than we do for them, who bring themselves and others down, and just aren't really who or what we need to be around.
Then there is the main point we want to reach here - of slowing down. At the core this aids in solving a great many of the issues we've touched on here. Slowing down and really listening to the world around us, to ourselves within our bodies and thoughts leads to a greater connection with the world at large. Learning to know what we need and how we need it enables us to achieve it on a much greater and fulfilling scale. When we slow down we're much more able to see those signs that are being sent our way in whatever form, including and especially of health. When we perform at breakneck speeds it's hard to notice the twinge in our knee, the weight on our shoulders, or that aching that signals what will later be a doozy of a migraine. Such activity masks our ability to observe and contemplate, while stillness promotes it.
When we put too much stress on our minds and bodies we deplete our vitality and strength. Doing this makes it harder to perform and ultimately puts unhealthy levels of unnecessary stress on our bodies which all the sooner revolt and break down as a result of it. For some illness and injury serve as a big red flag being waved wildly to take stock of their lives. While not every case may me to physically slow down, it certainly does mean a call to attention at what one is doing - both in life externally and internally to one's body.
So next time you're rushing out the door, thinking of all the things you have to do, wondering or concerned if you will get them all done. Take a moment to slow down. Notice how you feel, see where any negative feelings are coming from and really embrace them. What can you change about your actions and perspective to nullify them? Make this a conscious daily practice and notice how these troubles melt away.