I eat home made or at Whole Foods for lunch or I don't eat. I usually fix fish for dinner, eggs and bacon for breakfast. By all accounts I should be dead of a heart attack, my family is rife with heart disease. I'm 6'-1" 185#, 51 years old. I've never, ever been on a diet.
I think diets are stupid. Eat what your body tells you to eat. As long as you get regular exercise you'll be in tune with your nutritional needs.
Emotional stress without exercise will make you fat. Mark my words, science will figure it out one day but all you have to do is look at all the potato shaped people working in offices, dealing with artificial deadlines and brow-beating bosses day in, day out.
When you need lots of burnable calories, emphasize carbs, when you're in recovery, emphasize proteins. Eat vegetables and fruits every day. Drink water. Don't eat junk or most pre-packaged foods. Prepare your own meals or if you can't, have someone you trust do it. Whole Foods is awesome because the food is high quality, you can pick and choose and all the fit, earthy women go there to shop.
All that diet research is half baked because that's the nature of research, it's never complete and frequently back tracks on itself. Fads are bad for you and they make you look like an idiot when they're ultimately proven meaningless.
Eating is simple, do what's natural.
If you need to lose weight... EXERCISE... it's the only thing that works long term. Denying yourself regular calories in the climbing business is definitely bad for you.