Hello, I went through your query,, dehydration??!!!! The only solution for your problem is, drinking plenty of water, normally a healthy person should take 10-12 glass of water (250ml size glass), that is around 2.5-3litre of water, staying outside doesn't mean you have to eat junk foods, please avoid, high calorie bakery foods, panipuri, gobi, or other type of junk food.