KEY POINTS:
If all the brain food hype is to be believed, the nation's parents will be out there stocking up on nuts, tins of mackerel and broccoli to help boost their child's chances in next week's exams.
However, Dr Carol Wham, senior lecturer at Massey University's Institute of Food Nutrition, says a drastic change of diet simply because of exams could be counter-productive.
"It is an important period because they have a goal to achieve and they are under a lot of pressure. They do need nutritious food which doesn't make them drowsy or groggy, but that food has to be familiar, so nothing upsets them."
In the United Kingdom, supermarket chain Tesco has found sales of oily fish such as tuna and mackerel soared by 34 per cent over exam time in cities with universities. Avocado, bananas, peanut butter and melons were also big sellers.
It attributed the boost to the growing profile of so-called brain foods - reputed to help the memory and increase concentration.
Exams for about 136,000 students begin with level one physics on Monday and end on Saturday, December 9, with the German scholarship exam.
Ms Wham believes it is better to face realities when dealing with teenagers' stomachs.
"Some teenage kids would benefit from an egg on toast, but there is no point giving 15 to 17-year-olds egg on toast just because of an exam. The most important thing is to not miss breakfast. If they don't want anything, make sure they at least have a breakfast drink, or milk and a banana so they're not going out with nothing to eat."
While food cannot make a student sit at their desk and study, it can help with two problems - becoming drowsy or getting hungry during the exam.
Ms Wham says the most important factor in preventing drowsiness was to avoid high-fat meals.
She said small, frequent meals and snacks worked best, especially with protein which filled people for longer.
"Good snacks include chocolate milk, yoghurt or cheese and crackers because they have protein. They should have plenty of water to drink."
The humble cheese and vegemite or chicken salad sandwich made a good lunch, with fruit, and vegetables and pasta was a decent pre-exam-night meal.
Study time
* 135,735 will start exams from Monday - up from 132,241 last year.
* The number of students sitting scholarship exams has also increased from about 7000 last year to 7,700 this year.
* More than 50,000 students will sit level one English on Tuesday morning - the biggest exam.
* 43 students will sit level three Latin on Tuesday, December 5 - the smallest exam.
* The timetable and information for students is on the NZQA website.
