By coincidence, I came across a book that Mrs. D also likes. It is called
Food & Mood: The Complete Guide to Eating Well and Feeling Your Best
by Elizabeth Somer (Author) M.A. R.D, Nancy Snyderman

I use it as a resource and recommend it to folks all the time...you can buy it used at amazon.com

There are many good books out now re: the psychological aspect of portion control...
The Beck Diet for Life is good...also one by the same author that is more like a tool kit.

I do think it is a cycle of sorts...we can over eat or eat the wrong things due to emotional reasons. Certain vitamins, certain foods might be able to help regulate our emotions.

Very generally, I think Fish Oil, The B Vitamins and D3 seem to be really good at helping with anxiety/mood