I have the total opposite issue when depressed. My appetite is far lighter when in manic states, but then it's more forgetting than being at all incapable of eating.

I totally second pretty much every response here already. Definitely add the multi-vitamin if not a usual. The toast is not a nutritional powerhouse (though whole grains are the best), but for me was all I could eat during migraines. Far better than nothing! The natural peanut butter first entered my mind, too, as did the protein bars. For the latter, really examine the labels. Some are more protein and nutrient rich than others, and caloric.

Not mentioned yet is yogurt. It's nutritious and good for the stomach. Plain, with optional something added, is better than the flavored, but flavored work, too. Greek style has the most protein. In my view, full fat Greek is far more appealing than the low fat or fat free options.

Oatmeal or other grain cereals (porridge) are very good and easy on the tummy. I particularly like cold overnight oats, but also hot on occasion. If you happen to have chia or flax seeds, add a teaspoon of them, too. And maybe nut butter or nuts and fruit...and a dollop of yogurt.

Smoothies are also good.