How to boost your brainpower when studying for exams.

By Laurentia (Laura) Campbell. Brain and Food scientist

When studying it is essential that we nurture our brain health to ensure we maximize our memory and cognitive capacity. For this, we need to keep our energy levels balanced, ensure we get adequate sleep, and reduce stress as the cortisol from stress impacts the Hippocampus (memory centre) of our brains. Without food, you cannot think straight, but what you choose to eat over your revision period can hinder or aid your ability to focus and learn. There are some foods which science shows, help you eat yourself clever.

10 ways to boost your cognitive capacity

1) Never skip meals, especially breakfast. We eat for energy, and our brains need food. Try to eat at the same time every day in a routine that suits the way you learn and sleep. If you are an early riser, eat breakfast at 8, lunch at 1 and dinner at 7, with regular intervals and space for an 11 am and 4 pm snack if you need it, to ensure you maintain your energy levels for learning. If you are a night own and wake up late and work late, eat at 12, 5 and 9, again with snacks at 3 and 7 if you need to. Make sure you have breakfast as soon as you wake up (even if you are not hungry) as your Insulin (blood sugar) levels, peak 15 minutes after you wake up and without breakfast, you cannot think clearly. Feed your brain. The best breakfast will be one high in fibre (such as bran flakes, porridge, Weetabix, wholemeal bread toast), protein and fat (milk, yoghurt, seeds, butter, peanut butter, eggs, fish or meat) and some fruit or vegetable for vitamins and minerals. Ensure you have some water with every meal.

2) Reduce stress. Cortisol, the stress hormone, has been directly shown to increase cognitive decline, reduce memory and enhance emotional instability. Remember that you will not die if you fail one exam, what is the worst that can happen? Your life will not end. You will survive and there is always a solution to every problem. Breathe and put in place coping mechanisms which help reduce stress such as breaks with walks in nature, seeing friends, doing something creative, having a short power nap (as long you do this only in the morning as too much sleep in the day reduces sleep quality at night), time away from phones and doing things you enjoy that enhance Dopamine (the pleasure brain chemical). Enkephalins and endorphins (the pain, love and stress-reducing brain chemicals) from hugging loved ones, stroking a pet, exercising, music, dancing, and complimenting someone, also aid stress and increase memory. Our brains also see hunger as mental stress, so ensure you never get too hungry.

3) Make sleep a priority and watch caffeine. Ensure you get into a rhythm of at least 8 hours of sleep as sleep is essential for stress regulation and memory consolidation. To do this ensure you practice good sleep hygiene in a dark, cold room and a hot bath (to lower body temperature and enhance sleep) before bed and go to bed and get up at the same time each day. We fall asleep because of Adenosine (a byproduct of ATP from respiration, the process which makes energy, in all cells) from activity building up “sleep pressure” in our brain and helping us enter SWS (slow-wave sleep) and REM (rapid eye movement) sleep. An active day of studying causes the build-up of Adenosine. Exercise also increases Adenosine, providing it is not too late at night as late-night exercise increases Adrenaline, the hormone that makes you alert, which disrupts sleep. Caffeine blocks Adenosine receptors in our brain and it takes 5 hours for our body to break down caffeine, so whilst caffeine can enhance alertness and focus, ensure you don’t drink it at least 5 hours before you sleep. Stress increases Adrenaline, restricting Adenosine, so try to wind down before you sleep with meditation, relaxation, distraction, calming music and candles and other techniques to help you sleep.

4) Eat for sleep. Sleep can be aided by eating foods that are high in Melatonin. Melatonin is the body's sleep regulator, which works with the sun and Adenosine and Orexin (a sleep chemical) to regulate our sleep circadian rhythms. Foods high in Melatonin include eggs, milk, fish, and nuts. Magnesium also enhances a sense of calmness, reduces anxiety and aids sleep. It is found in green leafy vegetables like kale, spinach, broccoli, leek, spring onion, wild garlic leaves, fresh basil, fresh parsley, fresh mint, fresh chives, fresh coriander, avocado, Brussel sprouts, edamame, lettuce, peas, green beans, and chard, rocket, watercress, green cabbage, cauliflower leaves, cucumber, and celery. It is also found lots in nuts (especially almonds), beans, soy products, chickpeas, tofu and salmon and some cereals and dairy products are fortified with it. Alcohol can also help you fall asleep but stop the REM sleep essential for memory consolidation and emotional processing and so should be avoided over exam periods.

5) Eat lots of protein. Protein is needed for growth and repair. It is made in all cells from something called amino acids. When we eat foods high in protein, such as meat, fish, eggs, nuts and seeds, dairy, and soy products, we break down protein into amino acids. Brain chemicals called neurotransmitters are made of amino acids. If we don’t eat enough protein, we cannot make neurotransmitters, such as Serotonin and Dopamine, the happiness brain chemical and reward brain chemical. These both play a role in mood regulation (helping us regulate our response to stress), energy levels (happiness increases Adrenaline, making you hyper and energetic) and the formation of new brain cells (neurogenesis), helping us form new brain pathways and learn more.

6) Eat for sustained energy. We need carbohydrates for energy and not eating carbs can make you lethargic and tired, with brain fog, unable to remember key information. You cannot think without food. However, it is important you chose the right energy sources, that will not cause energy dips that will make you stressed and tired. High refined sugars (like chocolate, cakes, sweets, sugary sodas, pastries, and biscuits), cause quick and short-lasting energy supplies, which cause Insulin (the blood sugar regulator) to be released, and a massive dip in energy. To stop this energy dip, eat complex, low-GI (glycemic index- the ability of a carbohydrate food to increase blood sugar) carbohydrates that are high in fibre, such as those in starchy vegetables, whole grains, nuts, and seeds and high in protein and fat. Carbohydrates like wholegrain pasta, brown rice, wild rice, seeded wholemeal bread, potatoes, lentils, chickpeas (hummus) quinoa which also contain protein and fat have a lower GI and so will help you maintain your energy levels, problem-solve concentrate for longer, revise long into the night and remember more.

7) Eat lots of omega-3 fatty acids. Our brains are made of 60% fat. When we eat a type of fat, called Omega-3, which is found in oily fish like salmon, mackerel, tuna and sardines as well as Brussel sprouts, flax seeds, chicken and beef, walnuts, chia seeds and spinach, it increases neurogenesis (the formation of new brain cells and synaptic, between brain cells, pathways). Omega-3 fatty acids also have a good glycemic index, which helps you stay emotionally balanced and to concentrate for longer and learn.

8) Water. Staying hydrated is essential for learning. Evidence shows that regularly drinking water is necessary for maintaining energy levels. Drinking hot water or herbal teas is also soothing and can help calm and relax you, reduce stress and anxiety and help you sleep.

9) Try high fibre foods. Fibre is the structural component of many vegetables. There are two types soluble and insoluble. High fibre foods include broccoli, courgette, mangetout, sugar snap peas, green beans, sweetcorn, leeks and spring onions, wholegrain foods, wild rice, quinoa, potato skins and fruit like grape and apple peels. Fibre helps to increase the GI of foods, helping maintain your energy levels for longer. It also is prebiotic and so feeds the gut microbiota. The gut microbiota in turn release small-chain-fatty-acids (SCFAs) which enhance the release of Serotonin from the brain and help regulate the blood sugar and glycemic index of food, helping boost metabolism. Most high fibre foods are also high in B12, a B vitamin that is found in many green vegetables and fortified cereals and milk, and boosts brain capacity and energy levels and metabolism.

10) Avoid energy drinks and tablets. Though advertised as enhancing energy, most energy tablets and products cause a massive surge in energy that is fast-acting but short-lasting. This is great if you have two hours to finish an essay before a deadline, but if you are wishing to do long-term memory retention for exams, can have seriously unforgivable effects. They can cause extreme mental stress, fatigue, burnout, mental fog and loss of memory. The worse offenders of this are drinks like Gatorade or Lucozade sport. These are extremely high in sugar and are high GI products, which cause massive blood sugar spikes followed by massive Insulin hormone spikes and low blood sugar, leaving you tired, hungry, unfocused and unable to learn.

Overall, it is essential that you maintain your energy levels, sleep, and try to avoid illness. Try to eat lots of iron for energy (in broccoli, beef, eggs, and chicken) and vitamin C (needed to absorb iron and helps boost the immune system, protecting you from disease). Try not to stress too much over the exam period. Remember it will all be over soon, and you will survive no matter the outcome. Believe in yourself and your brain and do your best.

Copyright Laura Campbell 29/04/2022


1) Arab, A., Rafie, N., Amani, R. and Shirani, F., 2022. The Role of Magnesium in Sleep Health: a Systematic Review of Available Literature. Biological Trace Element Research, pp.1–8.

2) Benson, S., Tiplady, B. and Scholey, A., 2019. Attentional and working memory performance following alcohol and energy drink: A randomised, double-blind, placebo-controlled, factorial design laboratory study. PloS one, 14(1), p.e0209239.

3) Benton, D. and Burgess, N., 2009. The effect of the consumption of water on the memory and attention of children. Appetite, 53(1), pp.143–146.

4) Benton, D. and Nabb, S., 2003. Carbohydrate, memory, and mood. Nutrition reviews, 61(suppl_5), pp.S61-S67.

5) Holtzman, J.D., 2006. Food and memory. Annu. Rev. Anthropol., 35, pp.361–378.

7) Arden, J.B., 2010. Rewire your brain: Think your way to a better life. John Wiley & Sons.

8) Dubnov-Raz, G., Constantini, N.W., Yariv, H., Nice, S. and Shapira, N., 2011. Influence of water drinking on resting energy expenditure in overweight children. International journal of obesity, 35(10), pp.1295–1300.

9) Hanson, A.J. and Craft, S., 2015. The Impact of High Saturated Fat and High Glycemic Index Foods on Cognitive Function and Alzheimer’s Disease Biomarkers: Does a Typical Western



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Laurentia (Laura)Campbell

Laurentia (Laura)Campbell

Neuroscience, mental health and nutrition academic and writer. Life-experimenter, trying to add value with an insatiable appetite for actioning positive change.