Which food is need to take....i am reading 14 hours per day because exams are very near! help me to maintain my brain become more active?

Hang in there!: Avoid eating a lot of calories at once. Rather 200kcal every 2-3 hrs. Avoid sugar-you will only crash in 3-4 hrs. Likewise w excessive caffeine although small amounts can helpful. Tea can be a good option. Drink plenty of water. Watch intake of simple carbs like bread, pasta, pastries. Avoid fats, esp. Trans- & sat fat. Fruits, veggies, lean proteins are best rest eyes & take exercise breaks.