This week I wanted to examine a phrase I've heard lately: "Because of my depression (or anxiety, etc.), I'm tired for no reason."

Of course, there are healthy reactions that can cause a person to be tired. For example, after working 10 hours and working out for an hour, anyone's body would need a rest. Anyone would be nervous before an important presentation or test, and feel drained after the big event.

But if you are among the millions of people living with depression or anxiety, you have all the more reason to be tired, even if you didn't work out for several hours or take the GRE.

Fighting negative thoughts that you can't shake is draining. Adrenaline crashes from lack of sleep and panic attacks are draining. Being on the edge all the time, especially when dealing with school assignments and other jobs, is draining.

In depression where a common cause is low serotonin, this means the brain literally cannot make you feel awake because it's lacking the neurotransmitter that makes alertness possible.

With anxiety, the human body suffers a form of adrenaline burn out due to the hormonal imbalances in the brain. Until those hormones rebalance and the body emerges from the constant feeling of being "on edge," this will only continue.

In addition, mood disorders often hurt healthy eating schedules and habits. Trying to compensate with junk food or sweets for a quick mood boost while cramming for that test will result in a lack of vitamins, minerals, healthy carbs, and proteins - all essential to energy. Nutritional deficiencies not only worsen our moods, make us more susceptible to physical illness, but also leave us feeling lethargic.

Even for people who don't have genetic predispositions like low serotonin, depression or even just constant feelings of exhaustion are very possible. For example, after an abusive relationship or loss or a loved one, anyone can experience a mood disorder for any length of time even though they might have been unaffected otherwise. Grief is exhausting.

Like I wrote about last week, medication is a valid solution, as is counseling. However, a common side effect of medication is fatigue. So there's another completely legitimate reason to be tired, even if worse symptoms are alleviated.

So go easy on yourself - you're fighting a hard battle. People with mood disorders are not tired for no reason; they're tired because they have a condition that is tiring. It's a flaw in chemistry, not character.