Nutrition on the road - What, How and Why?

^ I think miro-o is saying not to worry about nutrition while on the road, which would make his list make sense.

This. If you can eat well anyway, just enjoy the extra appetite.

100k isn't too much, I'd say no special nutrition required, stop at shops and supermarkets and buy and eat what you feel like, stop at cafés for plat du jour or coffee when you can afford....always making sure you have some emergency reserves....muesli bars, water, bananas etc and buy something on Saturdays to see you through Sundays.

if weather is hot, eat lots of salty crisps

This is all sensible.

I find morning markets are usually cheaper and more interesting than supermarkets and olives / cheese / salumi all more enjoyable ways of getting salts than crisps. It's all personal preference though.