Sleeping in can be just as bad for our health as not getting enough sleep

Tuesday, July 22, 2014, 5:18 PM - Next time you get a chance to sleep in, you might want to reconsider turning off that alarm clock. Studies have shown that getting too much sleep can harmful, and just as bad as as getting too little.

You've decided to sleep in on your day off, yet once you're awake, you just can't get going and you feel even just as bad (or worse) than you do when you have to get up early. So, what's going on?

We may have our daily schedule - waking, commuting, working, eating, working some more, commuting again, dinner, all our evening activities and then sleeping - but plenty of that is dictated by a very basic part of our biology: our circadian clock. This clock can be adjusted back and forth if we change our location, but it generally tries to keep us on a schedule that matches up with how much daylight there is where we're living.

Included in this is getting a certain amount of sleep. It's well know, both in the scientific community and in the public mind, that getting less than the optimal amount of sleep has an impact on our cognitive abilities, making it harder to focus and concentrate, making it more difficult to form memories, and harder to perform mental tasks. We hear about this all the time. Not only that, if it becomes a more regular thing, it can raise the risk of heart disease and stroke, diabetes and depression.

However, too little sleep isn't the only problem. Due to our circadian clocks, there is an optimal amount of sleep for us each night, and it's just as harmful to get more than that as it is to get too little. A study out of Harvard Medical School showed that the optimal is amount is around 7 hours (varying slightly depending on genetics and environmental factors), and suggests this is what we should strive for every day - even the days we have off.

The key - as we hear in so many bed commercials - is the quality of sleep, rather than the quantity, as being 'sleep deprived' isn't always about how long we're out for.

Why is 7 hours the optimal amount of sleep? It may be that we evolved that way in more primitive times, as a recent study in Germany shows. The researchers put subjects in 'Stone Age conditions' for over two months - with none of the 'conveniences' (or distractions) of modern life - and examined their sleeping patterns. They went to be earlier and got more sleep than the average from their normal lives, and ended up with an overall average of 7.2 hours of sleep each night.

Giving some thought - after all of this - on giving up on sleep altogether? Well, that's probably not such a good idea either, as the ASAP Science video below illustrates: