Eat Smarter for Better Concentration Throughout the Day | Hardworkout Magazine

Key takeaways

- The brain mainly runs on glucose, but meals high in sugar and low in protein, fat and fibre can cause rapid blood sugar fluctuations and poor satiety.

- Amino acids from protein are precursors for neurotransmitters: tryptophan for serotonin, tyrosine for dopamine and noradrenaline.

- A very large meal can leave you tired and less alert, so a moderate portion is the better choice before tasks that demand concentration.

- Dehydration can affect attention, reaction time and the sense of fatigue, and large amounts of caffeine late in the day can disturb sleep and weaken concentration the following day.

- Diet is only one of several factors behind concentration, alongside sleep, physical activity, stress and breaks.

Have you ever noticed that it is harder to maintain concentration and focus when it has been a while since you last ate? Or that you become tired and unfocused after a large meal? What we eat throughout the day can affect how alert and concentrated we feel. The brain has high demands for both energy and nutrients, and our meals help meet these needs.

Why does concentration drop when you have not eaten for a while?

But what should a meal contain when you need to maintain focus for several hours? And are there foods that are particularly beneficial for the brain?

How to eat to maintain focus

The brain needs a steady supply of energy and nutrients to function normally throughout the day.

Carbohydrates provide the brain with glucose, while fiber-rich sources contribute to better satiety.

Protein supplies amino acids that the body uses to form several important neurotransmitters in the brain.

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Fatty fish provides the omega-3 fatty acids EPA and DHA, while nuts, seeds, and plant oils are good sources of unsaturated fat.

Iron, vitamin B12, folate, iodine, and several B vitamins have important roles in the nervous system.

Large meals can make you tired and less alert when you need to concentrate afterward.

Adequate fluid intake is important, while caffeine can temporarily increase alertness and attention.

Regular and nutritious meals should be combined with enough sleep, physical activity, and breaks for optimal mental performance.

How much of the body's energy does the brain use?

The brain makes up only a small part of body weight but accounts for a significant portion of the body's energy consumption at rest.

Under normal conditions, it primarily uses glucose as its energy source.

Does more sugar give better concentration?

Carbohydrates are broken down into glucose, which is absorbed into the blood and becomes available to the body's cells. However, this does not mean that large amounts of sugar lead to better concentration. Meals high in sugar and low in protein, fat, and fiber can cause rapid fluctuations in blood sugar and often poor satiety.

For most people, it is more practical to choose meals that provide both energy and good satiety.

Oats, whole grain products, potatoes, fruits, berries, vegetables, and legumes are good carbohydrate sources that also provide fiber, vitamins, and minerals.

Protein contributes amino acids the brain needs

Protein is often associated with muscles and exercise, but the amino acids from protein are used for much more than muscle building. Several neurotransmitters in the brain are formed from amino acids.

Which amino acids are used to make the brain's neurotransmitters?

Tryptophan is used, among other things, in the production of serotonin, while tyrosine is the precursor for dopamine and norepinephrine. These neurotransmitters are involved in attention, motivation, mood, and alertness.

This does not mean that large amounts of one specific protein source automatically lead to better focus.

A varied diet with sufficient protein ensures that the body gets the amino acids it needs. Eggs, fish, meat, milk and dairy products, legumes, tofu, nuts, and seeds are good sources.


Fat is important for the brain

Fat is part of the cell membranes in the brain, and certain fatty acids are particularly important for normal brain function.

The omega-3 fatty acid DHA is found in large amounts in the brain and is an important part of the membranes of nerve cells.

Fatty fish such as salmon, mackerel, herring, and trout are good sources of the marine omega-3 fatty acids EPA and DHA. Nuts, seeds, avocado, and plant oils also provide unsaturated fat and several other nutrients.

Here, it is primarily the diet over time that is important.

A meal with fatty fish does not necessarily lead to noticeably better concentration a few hours later, but regular intake of nutritious food contributes to normal brain function.

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Vitamins and minerals also matter

Several micronutrients are necessary for energy metabolism and the nervous system.

Iron is important for the transport of oxygen in the blood. Iron deficiency can lead to fatigue and reduced physical and mental performance.

Vitamin B12, folate, iodine, and other B vitamins also have important roles in the nervous system.

A varied diet meets the needs of most people, while individuals with deficiencies or increased risk of deficiency may need supplements based on individual assessment.

Large and heavy meals can make you tired

The composition of the food is not the only thing that matters. The quantity can also affect how you feel after the meal.

How much should you eat if you need to concentrate afterwards?

A very large meal can make you feel tired and less alert afterward. If you need to return to work, studies, or other tasks that require concentration, a moderate meal may be a better choice than eating a lot at once.


Don’t forget fluids

Even a good diet works poorly if you drink too little.

Dehydration can affect attention, reaction time, and the experience of fatigue, especially when fluid loss is greater.

Water typically covers most of the fluid needs.

Can coffee and tea count towards your fluid intake?

Coffee and tea also contribute to fluid intake, while caffeine can temporarily increase alertness and attention. The effect depends, among other things, on the dose and how accustomed you are to caffeine.

Large amounts of caffeine late in the day can also disrupt sleep, which in turn can weaken concentration the next day.