Boost your brain power at exam time
For students under pressure, what they eat can be as important as what they study
Published 26/05/2014 | 02:30
GOOD nutrition is vital at any time of year, but especially during exam time when your brain and body are under particular stress.
The right diet and exercise routine can give you energy and improve your mental alertness, while a poor diet will only make you feel sluggish and jittery.
To understand the importance of what to eat and what to reduce, I'm giving you a quick crash course in brain biology to help you make better food choices. I have highlighted a few readily available foods that you probably already enjoy, are easy to prepare and won't implode the grocery budget.
Brain Biology 101: Sugar Roller Coaster
Our brains are incredible organs which control every thought, movement, and sensation, every second of every day. Whether we are awake or asleep. This makes our brain the most energy hungry organ in our bodies, weighing only 2 per cent of our total body weight but consuming more than 20 per cent of our calorie intake.
We know that how we eat can affect our bodies, but what we put in our mouths also affects our mood, the brain's energy, our memory and even our ability to handle stress, complex problems, or simple daily tasks. This is of heightened importance during times of intense mental stress, like exam time.
The brain demands a constant, steady supply of glucose to keep it running. Glucose is the basic building block of carbohydrates. Neurons don't store this basic sugar like other cells, so they are always hungry. We obtain this fuel from the carbohydrates we eat such as in fruits, vegetables, and grains. The brain may run on sugars, but this doesn't mean we can eat sugary junk food. Refined sugars, like table sugar or fizzy drinks can cause overly high blood glucose levels, or sugar spikes, do damage to cells throughout the body, including the brain, and can literally starve our hungry neurons.
Insulin is a hormone that encourages cells to absorb and store glucose. As glucose enters the blood stream from digestion, the pancreas releases just the right amount of insulin to keep blood sugar under control. But, when we consume refined sugars, glucose levels rise too high too fast for the body to control it in the normal way. The body and pancreas go into overdrive to try balance this dangerously high blood sugar level.
These emergency measures reduce the dangerously high blood sugar levels, but often they fall too low when the body has been forced to react so drastically. This is why so many people experience a crash shortly after the rush that comes with sugar. We flood our system with fuel and it feels good, but then our bodies have to do something with the excess fuel and the levels drop well below normal. Since our neurons can't store glucose like other cells, they starve during this crash. This forces the brain to rob glucose from nearby fluids and then it becomes sluggish as it runs low.
Our memory and focus suffer during these low points and the repeated roller coaster continually damages our neurons. That 3pm chocolate bar is doing untold damage to you, so let this be a wake-up call!
Healthy fats are vital to healthy brain function. Our brains are made up of 60 per cent fat and low levels of fats in food and the body can contribute to depression, Alzheimer's, dementia and learning difficulties. Choose good, healthy fats like those found in seeds, nuts, fish, coconut and avocados.
These contain the essential omega 3 and omega 6 fatty acids that we need for health, along with non-essential fatty acids that are also beneficial.
Saturated fats should be used in moderation, but can still be a part of a healthy diet, especially coconut oil which has shown some promise in raising good cholesterol levels, weight loss and combating brain disorders and degeneration. Trans fats found in hydrogenated vegetable oils are the ones to cut down on or avoid altogether. These raise cholesterol, damage the heart and the brain, and contribute to heart disease, obesity and diabetes. Focus instead on adding fish and good plant-based foods that improve brain function, mood and memory.
Easily Accessible Top Brain Foods
This buttery fruit is rated as one of the top all rounders for brain function, packed with monounsaturated fat which improves blood supply to the brain, bringing oxygen and vital nutrients.
The omega 3 fatty acids and vitamin E protect the brain from free radical damage. Rich in folic acid, avocados also support the nervous system in stressful times. Avocados can even reduce your risk of having a stroke. A quarter to half an avocado a day is enough to reap the benefits.
These berries are antioxidant powerhouses, protecting the brain from oxidative damage and stress that lead to premature ageing, Alzheimer's and dementia.
The flavonoids in blueberries also improve the communication between neurons, improving memory, learning and all cognitive function, including reasoning, decision making, verbal comprehension and numerical ability.
Other dark berries are good for the brain too, like blackberries, acai and goji berries. Frozen blueberries are more budget friendly and excellent in smoothies, keeping the drink chilled and more pleasant to drink.
Broccoli is a superfood for the whole body. It is rich in calcium, vitamin C, B vitamins, betacarotene, iron, fibre and vitamin K. These nutrients protect against free radicals, keep blood flowing well, and remove heavy metals that can damage the brain.
Vitamin K is known to enhance cognitive function and improve brainpower.
If you don't fancy broccoli, other vegetables from the Cruciferous family such as cabbage are equally beneficial. Coleslaw anyone?
Intense concentration and stress can leave students craving sweet treats even more. But to prevent roller coaster blood sugar dips and dives, choose high in cocoa and low in sugar dark chocolate. This will satisfy that sweet craving and give you an antioxidant and mood boost at the same time.
The flavonols in chocolate improve blood vessel function, which in turn improves cognitive function and memory. Chocolate also improves mood, can ease pain and is full of antioxidants. No convincing needed I'm sure!
Nuts, especially walnuts, Brazil nuts and almonds, are extremely good for the brain and nervous system. They are great sources of omega 3 and omega 6 fatty acids, vitamin B6 and vitamin E.
Vitamin E has been shown to prevent many forms of dementia by protecting the brain from free radicals, and it improves brain power. Nuts make an excellent snack on their own, or you can try delicious nut butters from health shops or try making your own using whole nuts ground to a paste in a food processor.
I know I mention wholegrains later on, but I feel oats deserve a whole section on their own. Oats are an ideal breakfast choice as they are a complex carbohydrate, full of fibre which releases it's energy in a nice steady stream.
Oats are packed with B vitamins which are a first line defence in supporting the nervous system against stress. Additional B vitamins are also very effective as an energy boost. Pinhead oatmeal is the most unrefined porridge which will give you the most sustained energy, but regular porridge oats are excellent too.
I have mentioned essential fats several times, but here is a quick reminder of why they are important. Essential fatty acids (EFAs) cannot be made by the body and must be obtained through diet.
The most effective omega 3 fats occur naturally in oily fish as EPA and DHA. Good plant sources include linseed (flaxseed) oil, chia seeds, pumpkin seeds, walnuts and soya beans.
EFAs are good for healthy brain function, the heart, joints and general wellbeing. Oily fish contains EPA and DHA in a ready-made form, which enables the body to use it easily.
The main sources of oily fish include salmon, trout, mackerel, herring, sardines, pilchards and kippers.
Low DHA levels have been linked to a higher risk of developing Alzheimer's disease and memory loss.
Just a handful of pumpkin seeds a day is all you need to get your recommended daily amount of zinc, vital for enhancing memory and thinking skills. Zinc also helps boost your immune system which is very important during exam season when a cold or flu can really impede your performance.
Sunflower seeds and other seeds, like pumpkin, contain a rich mix of protein, omega fatty acids, and B vitamins. These seeds also contain tryptophan, which the brain converts into serotonin to boost mood and combat depression and stress.
Rosemary has been shown to improve memory and cognitive function with its scent alone. It improves blood flow to the brain, lifts mood and acts as an antioxidant. Rosemary is also a powerful detoxifier, fights cancer, boosts energy, and combats ageing of the skin. Buy a little pot of rosemary, snip off what you need for cooking and keep it next to your study desk.
Like everything else in your body, the brain cannot work without energy. As we mentioned, the brain uses glucose. Our ability to concentrate and focus comes from an adequate, steady supply of glucose in our blood to the brain.
Wholegrains have a low-GI, which means they release glucose slowly into the bloodstream, keeping you mentally alert throughout the day. Opt for unrefined 'brown' cereals, wheatbran, granary bread, brown rice, brown pasta. Try other grains such as quinoa, buckwheat and millet for variety.
Wholegrains generally have plenty of B vitamins if they are unprocessed, which gives you energy and helps feed the nervous system.
After several hours of sleep, your body has been fasting and needs refuelling. What you choose for breakfast really sets you up for the day. Choose a complex carbohydrate and add healthy fats, fruit and protein for a complete meal.
For the most sustaining breakfast, cook pinhead oatmeal and serve with banana, blueberries and flax seed.
Cook porridge oats with a little cinnamon and sprinkle with berries and nuts of your choice.
Bircher muesli is made by soaking oat flakes in milk or apple juice for 20 minutes and serving with fresh fruit, nuts and seeds.
Make a smoothie by blitzing one banana, two tablespoons of nut butter and enough milk or non-dairy milk to get the consistency you like.
Homemade oaty flapjacks with cinnamon, dried fruit seeds and nuts.
Greek yoghurt with fresh fruit, nuts and seeds or muesli.
Homemade or low sugar baked beans on brown toast.
Scrambled omega rich eggs with smoked salmon and steamed asparagus.
Spinach and feta cheese omelette made with omega rich eggs.
Buckwheat pancakes with ham and grated cheese.
Eating little and often is an excellent strategy for maintaining energy levels and a steady supply of glucose to the brain.
Aim for three meals and a mid-morning and mid-afternoon snack and a small snack one to two hours before time. This will help maintain your blood sugar levels while you sleep, staving off early morning bouts of insomnia and panic.
Combine fruits, vegetables and complex carbohydrates with healthy fats and proteins.
A crisp Granny Smith apple cut into wedges and dipped in one to two tablespoons of nut butter.
A few oat cakes spread with nut butter and a little honey.
Rye or wholewheat crisp bread spread with cottage cheese, sliced tomatoes and chives or basil.A small handful of sunflower seeds mixed with raisins.
A small handful of macadamia nuts, dried cranberries and pieces of dark chocolate.
Popcorn sprinkled with sea salt and paprika with a handful of cashew nuts.
A cup of vegetable soup with a brown toast fingers.
A plate of chopped raw carrots, mange tout, cucumber, baby corn and peppers served with hummus or bean dip.
A wholewheat wrap filled with hummus and grated carrot.
Cooked beetroot topped with crumbled feta cheese and pumpkin seeds.
H2O your new BFF
Adequate liquid intake is often forgotten when talking about brain performance and stress.
We need to consume at least 1.5 to two litres of fluid per day to keep properly hydrated. Dehydration can make you feel lethargic, irritable and tired. Worst of all, it affects your concentration which may make it more difficult to study and perform at your best.
Keep a glass of water, diluted fruit juice or herbal tea within easy reach while studying and carry a bottle of water with you at all times.
Fizzy drinks are pure sugar and poison for your brain, so try fruit teas and create your own iced teas instead. Caffeinated drinks are often guzzled so that students can stay up later and study longer hours. But try to reduce your intake of drinks that contain caffeine, such as tea, coffee and colas as they can act as mild diuretics. This causes the body to lose fluid and increase the need to use the toilet, which is not good during an exam.
Although some studies suggest that small amounts of coffee can make us alert, other studies suggest that taking excess caffeine can upset our blood sugars which can affect your concentration levels.
Caffeine will also play havoc with your sleep patterns so reduce your intake to one to two cups a day, with nothing after 4pm.
All recipes taken from 'Delish and Relish Cookbooks' by Rozanne Stevens.
Health & Living