Can food improve your exam performance?
by Dr Alex Richardson
When you're faced with a pile of revision, feeding your body as well as your brain may be the last thing on your mind. But can you give yourself an advantage simply by eating certain foods? And does drinking plenty of water really increase your chances of getting good grades?
Whether you're a student or the parent of a child sitting school exams, there are quick and easy food tips to help maintain those all-important energy levels and improve concentration and memory.
What's the best breakfast on exam days?
Research shows that pupils and students who eat breakfast perform better in exams. For the best breakfast, include slow-release carbohydrates, such as whole rolled porridge oats, whole grain bread or low-sugar muesli, as they provide slow-release energy. Add a protein food, such as milk, yoghurt or eggs, to keep you feeling full for longer. On exam day aim to include a portion of a food rich in long-chain Omega-3 fats, such as smoked mackerel, as they are believed to have brain-boosting properties. Take a look at our collection of exam-day breakfast ideas for some inspiration.
How can drinking water improve your grades?
One of the best ways to maximise your focus is to stay hydrated. Even mild dehydration can lead to tiredness, headaches, reduced alertness and diminished concentration.
Take a bottle of water into the exam if you’re allowed to; a study of university students found that those who brought drinks, especially water, with them into the exam performed on average 5% better than those who didn't.
Start the day with a big glass of water or fruit tea. The European Food Safety Authority recommends women drink about 1.6 litres of fluid a day and men 2 litres. That's eight to ten 200ml glasses. Water is ideal, but healthy drinks such as milk and small amounts of fruit juice count.
Tea and coffee count too, but are high in caffeine. It's best to avoid sweet fizzy and energy drinks, which are high in sugar, as they'll lead to energy peaks and troughs.
Which foods will help you focus?
Eating a balanced diet can help you focus and avoid illness. No single food is nutritionally complete, so you need variety. Try not to skip meals or your blood-sugar level will drop.
In the West we eat far too much Omega-6, found in vegetable and seed oils, and too little Omega-3 (which is important for brain power), found in oil-rich fish and seafood. It is important to limit your Omega-6 consumption. This means limiting products made from these oils, such as some margarine, as well as the oils themselves.
Vegetables contain fibre, which slows down digestion, causing energy in food to be released more slowly and so helping you to avoid energy peaks and troughs. Good sources of fibre include carrots and broccoli. Iron is particularly key during exam time, as a deficiency (identified in over 40% of teenage girls) leads to tiredness and lack of focus; dark leafy greens are a source.
Fibre slows down digestion and so causes energy in food to be released into the body more slowly; apples, pears, raspberries and bananas are good sources. Try sprinkling frozen berries or dried fruit on to porridge. Vitamin C is needed for your immune system, and is found in fruit and vegetables; oranges and kiwi fruit are particularly good sources.
Oil-rich fish and seafood are important for brain health and concentration, thanks to their ‘long-chain Omega-3s’. About 8% of the brain is comprised of Omega-3 fats, and we should eat a portion of Omega-3-rich foods at least 2 days a week. It’s condensed in salmon, sardines, fresh tuna (not canned), trout and mackerel; even fish fingers contain some. Supplements may be considered, especially in exam periods. Short-chain Omega-3s, found in nuts and seeds, are less effective as we can struggle to convert them into long-chain ones. Young women may benefit from boosting their iron with red meat.
Slow-release carbohydrates such as whole grain bread, wholemeal pasta, brown rice and porridge help keep your blood-sugar level stable, averting dips in concentration and brain power. Research indicates only 17% of adults and 6% of children are eating enough whole grains. Eating three slices of whole grain bread or one bowl of whole grain cereal with one slice of the bread per day will provide all the whole grains you need. Some whole grains, including wheat, are a good source of zinc, and zinc deficiency in children is associated with hyperactivity.
What should you eat for a good night's sleep?
Not getting enough sleep may negatively affect your memory and slow your responses. Experts believe memory neurons that are responsible for converting short-term memories into long-term ones work most effectively when we are asleep. There's evidence that students who sleep for seven hours a night do on average 10% better than those who get less sleep. But what should you eat and drink at bedtime to promote sleep?
A heavy meal too close to bedtime can interfere with sleep, so try to have your last meal at least three hours before you go to bed. Then have a small snack such as a bowl of high-fibre cereal like porridge just before bedtime. If you need sweetener with cereal, go for dried fruit rather than sugar.
Avoid foods and drinks that contain caffeine, such as tea, coffee, cola and chocolate, for least four hours before going to bed. Some people who are very sensitive to caffeine can still feel the effects 12 hours later. A warm glass of milk at bedtime can help you sleep better.