Exam days and the ones during preparation can be very stressful. There is a build up of anxiety, confusion due to the vast syllabus and no sense of direction (for most).
Students tend to neglect their diet, eat what they get or just eat junk. Can this affect your exam performance- no doubt it does. Simply eating breakfast is really important - if you don’t your concentration levels will dip. But if you're holed up revising in a library all day, the temptation to grab a Snickers bar from the vending machine can be too great to deny.
It’s easy to remember that excess of carbohydrates or fats tend to make you sleepy (opposite of what is needed). Particularly refined carbohydrates give you swings in blood sugar and so in mood. It is far preferable to nourish your body with wholesome foods containing plenty of fruits and vegetables. Foods high in protein also tend to keep you alert and give sustained energy.
If you are in a habit of studying late nights, always keep a supply of salads and fruits to snack on, rather than biscuits or chocolates. Snack smart on fresh fruits (bananas), dry fruits, honey-coated nuts, seeds, roasted whole grains, soups, salads or yogurt to prevent swings in blood sugars and cravings. These fill you with good nutrition without making you dull or constipated.
Some students like to supplement with multivitamins- which is not a bad idea. If you don’t get good food, then a good vitamin helps.
Finally, don’t forget to keep yourself (& your brain) well hydrated. Keep your water bottle filled and keep sipping from it. If your waterworks (urine) is dark coloured, then you need to increase water intake.
Just like sportsmen pay attention to their diet for competition, preparing for exams also needs some attention to a healthy balanced diet.
You will see a difference in performance with a clearer thinking.