Even outgoing people may find themselves refusing invitations or making up excuses to avoid social contact. For many millions of people this is most apparent during the winter months when long nights, short days and lack of exposure to natural daylight leave them feeling fatigued, depressed, anxious and irritable. Known as winter onset seasonal affective disorder (SAD)some experts consider SAD to be an evolutionary hangover.

Most people with depression find their motivation drops through the floor. They slow down, speak more slowly, move about as if carrying a weight on their shoulders and dragging weights around their ankles. Even periods of mild depression show in facial expressions and gestures, both of which reduce in number. It becomes easier simply not to do anything. This can include getting out of bed, getting washed, eating and even drinking.

Pessimism and procrastination are firm buddies during depression. You may know there are things you could do to elevate your mood but your pessimism is saying it isn’t worth it. This fuels procrastination. If you’re a person already a little prone to putting things off depression will increase this further. It provides a sense of relief that you don’t need to make the effort. The down side is that it fuels depression and can add to guilt.

Some people go off food when their mood is low and others crave comfort foods. It’s a little unusual during depression to find that diet isn’t affected in some way, even if it’s simply the choice of foods that are preferred.