5 Surprising Signs You're Sleep Deprived - MSN Health & Fitness - Sleep Disorders

The most interesting one for me was that hormones are affected and real chemical changes occur!

Studies show that chronic sleep loss can disrupt blood sugar levels and cause the body to produce less leptin, a hormone that curbs appetite, and more ghrelin, leptin's hunger-stimulating counterpart. Because of these physiological changes, you may be more likely to overeat when you skimp on sleep—and the food you pick probably won't be either nutritious or a lasting source of energy.

So much for the science of diet focusing on food as the primary factor!!

The note about caffeine and calories is definitely true in my experience. Starting when I was in college, I noticed that I had much more sustained energy if I ate a small meal when consuming caffeine than when I just had caffeine by itself. I also noticed that I was much less prone to getting a case of caffeine-induced jitters with a small meal than with caffeine alone. A cup of coffee is not an adequate substitute for breakfast, and I wish some of my coworkers would realize that. Their growling stomachs are a major distraction in morning meetings.

Oooops, I'm sleep deprived.