Light boxes can certainly help you to overcome those feelings of depression and stop the comfort eating. Spending around 90 minutes in the light of a SAD light box while you work or read, or watch TV can have a significant effect on your condition.
The light supplied by a lightbox is measured in Lux and you ideally need around 10,000 lux to simulate bright daylight.
We sell the very popular Lumie Brightspark which provides 10,000 lux at 30cm.