This article looks at how nutrition affects our brains, and whether eating and drinking the right things as part of a healthy balanced diet can improve our brain health.
What does the brain need in order to function?
The brain is energy-hungry and uses one fifth of all the blood pumped by your heart – so food and drink are very important to keep it working properly. Here are some of the things it needs.
The brain uses glucose for fuel, which is made from carbohydrates in the diet. Complex carbohydrates, found in starchy foods like wholegrain bread, pasta and rice, are the best way to provide these. They release energy slowly, and help the brain to function in stable way.
- Top tip: For better concentration and mental performance, choose wholegrain foods (like wholemeal bread) instead of refined versions (like white bread). Avoid sweets and sugary foods.
Essential fatty acids
The ‘dry weight’ of the brain is about 60% fat, and 20% of this fat is made from the essential fatty acids omega-3 and omega-6. Essential fatty acids cannot be made by the body so they have to come from the diet.
Omega-3 and omega-6 are found in equal amounts in the brain, and it is believed that we should also eat them in equal amounts. But most of us eat much more omega-6 (found in foods like poultry, eggs, avocado and nuts) than omega-3 (found in oily fish like salmon, herring and mackerel. Plant sources include seeds, especially flax seeds, and nuts, especially walnuts).
Trans fats, also known as hydrogenated fats, are particularly bad for the brain because they stop essential fatty acids from doing their work effectively. They are found in many ready-made foods like cakes and biscuits – check the label for “hydrogenated” fat or oil and avoid these foods where possible.
- Top tip: Eat more oily fish – as a rich source of omega-3 it is very good for the brain. Avoid processed foods.
The neurotransmitters in the brain, which affect our moods, are made from amino acids. Some of these amino acids come from what we eat and drink. For example, serotonin, which helps us feel content and is important for sleep, is made from the amino acid tryptophan, found in milk, oats and other foods.
- Top tip: The food you eat really can affect your mood. For a good night’s sleep, choose food and drink rich in tryptophan – such as a milky drink before bed.
Vitamins and minerals
Vitamins and minerals are really important for the functioning of your whole body. The brain uses vitamins and minerals to help perform vital tasks such as making amino acids into neurotransmitters, and converting carbohydrates into glucose for fuel. Therefore a vitamin or mineral deficiency can affect your mood, as well as other brain functions.
- Top tip: Get a balanced diet by eating a variety of foods, including plenty of fruit and vegetables. Unless your doctor has advised you to take supplements, this should be enough to provide you with all the vitamins and minerals you need.
The brain is about 80% water, so it is important for us to drink lots of fluids for it to function properly. We lose about 2.5 litres of water each day through our sweat, breath and urine, and in order to replace the water we have lost, we should drink 1.5 litres of non-alcoholic fluids every day. (The rest of the water we lose is replaced by fluids in the food we eat, and by chemical reactions in the body).
If we don’t drink enough fluid, this can affect our mood and concentration.
- Top tip: Drink 6-8 glasses of fluid every day! Water, milk and fruit juice are all healthy ways to keep hydrated. Tea and coffee are OK as long as you don’t get all your fluid from caffeinated drinks. Avoid sugary drinks.
Foods and drink to boost your brain
There are some foods that seem to be particularly good for our brains. Eat them as part of a balanced diet, with regular meals. Always eat breakfast, as this will help your concentration and mental performance throughout the day.
Foods that are good for the brain include:
- Oily fish, such as salmon, herring and mackerel. These are an excellent source of omega-3, which your brain needs to stay healthy.
- Olive oil, which is a healthy source of fat in the diet and can help reduce cholesterol levels and blood pressure. Some studies have linked olive oil with a lower risk of ischaemic stroke, cognitive impairment and Alzheimer’s disease.
- Berries and other deep coloured fruits and vegetables, such as strawberries, blueberries, blackberries, acai berries, spinach, beetroot and beans. These foods are high in antioxidants, which help guard against disease by protecting cells in the body and brain from damage.
- Foods containing ‘good fats’, like nuts, seeds and avocados. Foods containing polyunsaturated fatty acids (nuts, seeds, fish and leafy green vegetables) and monounsaturated fatty acids (olive oil, avocados, nuts) may reduce your risk of both depression and dementia.
- Dark chocolate in small amounts! It contains high levels of antioxidants, but is also high in sugar and fat. One small piece of dark chocolate per day is enough to get the antioxidant benefit.
- Green tea, which is another rich source of antioxidants.
Food and drink that is bad for the brain
There are also some foods which are particularly bad for our brains:
- Salty foods like crisps, tinned soups and ready meals. We know that salt causes high blood pressure, which increases our risk of stroke. Government guidelines state that you should eat no more than 6 grams of salt per day.
- Sugary foods and drinks like sweets and cola. These may give us a temporary energy kick, but the energy is released so quickly that we soon “crash”, feeling low and lethargic. Too many sugary foods and drinks in the diet can also make us overweight, which increases our risk of health complications.
- Trans fats, which are often present in ready-made foods. Trans fats are particularly bad for us and may increase our risk of ischaemic stroke. They are also known as ‘hydrogenated fat’ or ‘hydrogenated oil’.
Is alcohol good or bad for the brain?
Some studies indicate that drinking alcohol in limited amounts may have a beneficial effect on our health, reducing our risk of dementia and heart disease. Red wine is often cited as having particular health benefits, perhaps due to the antioxidants it contains.
However, the risks of drinking alcohol may outweigh the benefits. We know that drinking too much alcohol is bad for the brain, and bad for our overall health. Even in amounts lower than the Government’s recommended daily limits, alcohol has been associated with a higher risk of certain cancers and according to a special report by the NHS, there is no “safe” level of alcohol with regard to cancer risk.
The report concludes:
“Alcohol should not be seen as an option for improving health, and it’s best not to pay too much attention to studies or stories that highlight its ‘benefits’ without also mentioning the risks.”
Can food and drink cause brain conditions, or prevent them?
Unfortunately, having a healthy diet cannot guarantee that you can avoid a brain condition – but it could reduce your risk. Equally, some people who eat unhealthy foods on a regular basis may not develop a neurological condition – but they are more likely to do so than if they ate a healthy diet.
While diet is a very important aspect of our lifestyle and does have a big effect on our health, it is just one factor among many different things that can come together to make a brain condition more likely. Some of these are out of our control, such as family history and gender. Some are other lifestyle factors, such as whether you smoke or drink alcohol, and how active you are.
Links for more information
There is lots of useful information about food and nutrition on the NHS website.
Food for the Brain is a non-profit educational charity, created by a group of nutritionists, doctors, psychiatrists, psychologists, teachers and scientists to promote the link between nutrition and mental health.
Brain food quiz: This quiz from WebMD tests your knowledge of foods that can boost your memory and protect your brain.
The Linus Pauling Micronutrient Information Center has detailed information on the roles of vitamins, minerals and other nutrients in preventing disease and promoting health.