Through lost sleep, a heavy caffeine habit can lead to weight gain and fat retention resulting from cortisol increases in the system following sleep deprivation. (blog.fitplanapp.com)
When stress is elevated for a long period of time, the stress hormone cortisol increases and as a result, people start retaining water. (physiqonomics.com)
The problem with stress is that elevated levels of cortisol increase fat around the waist and break down muscle mass. (thegreentribe.com)