Could my depression be caused by my thyroid or something i'm eating?

Hi everyone.

I was diagnosed with depression a couple of months ago. Along with my depression has been a loss of appetite (i maybe feel hungry a couple of times a week), until the last couple of days i've eaten for the sake of eating.

Anyway, the last 3 days i've only been eating one meal a day. Yesterday i felt the best (mood wise) i have in weeks and today the best i have in months.

Now this could be pure coincidence or, has my diet (or lack of it) improved my mood. Now i know this may be a loose connection, but thyroid can affect appetite and metabolism.

So my loose theory is, is my depression caused by my thyroid, possible evidence being not eating has caused my symptoms to lessen.

Suggestions/comments?

TL:DR Curious how a lack of eating, has caused my depression symptoms to lessen, possible thyroid connection?