This isn't necessarily anything new, but when I read it I commended them for putting a bunch of solid and easy-to-follow advice together.
It's on the site for a new-ish (predominantly) muay thai school here in Toronto. Check out the different parts of the site anyway because it's pretty good, but specifically look at the "TIPS" section. It's got all the fundamentals of striking, and a really good section on changing your eating habits to get in shape (which is why it's in this section).
http://www.tkmt.ca/index.html
Edited to Add: You'll notice that in the diet they provide for initial weight loss, they advocate egg whites as a protein source with every meal. Egg whites are great because they contain protein and iron and B12 and if you get the right kind they can provide omega fatty acids too, while having basically none of the fat or cholesteral contained in the yolk. However, I think I'd go nuts eating all those eggs every day, so I think it's fine to substitute protein shakes, tuna (packed in water and NO MAYO), or skinless chicken breast (a portion small enough to fit in the palm of your hand) and make sure you're getting a good multi-vitamin.