Apart from getting absolutely cranky and wanting to shoot everything in the line of fire, there are other side effects of not sleeping enough. The problems you ascribe to other things like bad food and cold weather are usually the result of not getting sleep for a good number of hours.
Ideally, an adult needs 7-8 hours of sound sleep in order to function efficiently the next day. But with the influx of Facebook, Instagram, Snapchat and other social media platforms, sleeping for 5 hours is considered to be a blessing.
Sleeping enough is also a healthy habit that one can cultivate. It will boost your sex drive and keep you fit.These infographics by Business Insider perfectly explains what loss of sleep does to your body:
If you sleep enough, you'll be able to remember better, and stay clear of common cold and tummy issues.
Here's the full infographic: