pre-marathon four week weight loss

Keep a food journal. Seriously, write down everything you eat, as you eat it, for at least the next week or two... or until your marathon.

If you are like 99% of people, you are eating a lot more crap than you realize, or will admit to yourself. Most people don't eat nearly as healthy as they think they do.

Forcing yourself to write down everything will create awareness, and you'll avoid a lot of the "bad stuff" just because you won't want to have to write it down and see it on paper.

If you are at high training levels, be careful starving yourself. Eat as much fresh as you can. Veggies, fruits. Consider cutting out out the PB&Js, and energy bars, and even the chocolate milk... too calorie dense.

Okay, for four weeks I will keep the food diary if it kills me. Thanks.

How to fuel runs - especially long runs - without some kind of bar or other energy dense food - without the danger of bonking?

This is not a good time to lose weight, but try something like this:

Calories: 2000 or slightly under

Protein: 160 grams

Carbs: @100 grams

Discontinue in last week.