Using Glucose For Mental Clarity And Focus: What You Need To Know

While consuming regular meals is an important part of maintaining blood sugar levels, sometimes we need an extra boost, for example, if we have episodes of low blood sugar (hypoglycaemia). Unfortunately, work and home life can be demanding and require focus even when we are not at our best. Using glucose tablets to raise blood sugar back up to normal levels can increase mental focus and help complete tasks that require concentration.


How Blood Glucose Impacts Focus

Fluctuations in blood sugar can have significant impacts on brain function. Many of us are familiar with sugar crashes and using snacks or comfort food to help us focus, but how does this work?

It may be because the brain requires a lot of energy to function at a high level. Just like muscle cells, brain cells make energy from glucose and oxygen. Research shows that, when performing a demanding mental task such as a memory test or problem-solving exercises, our blood glucose level decreases more rapidly than when performing a less demanding task such as reading.

This fast use of glucose is understood to be caused by energy production in the brain. Our brains are the most energy-demanding organ because they are so rich in nerve cells. The brain uses up to 50% of all the glucose we consume, so it is no wonder our focus and memory are impacted when our blood sugar is low.

In fact, low blood sugar has been shown to lead to a variety of symptoms due to reduced brain function, including:

  • Lack of concentration
  • Mood swings
  • Poor memory
  • Stress

It’s important to keep blood glucose levels at safe levels, typically between 4-5.6mmol/L, to help the brain function properly.

Research suggests that the brain takes in glucose more quickly under conditions of mild stress, such as challenging mental tasks. Further, glucose can increase serotonin and other neurotransmitters in the brain. These are chemicals which transfer signals between nerve cells and support emotion regulation, motivation, attention and more.

However, when blood sugar is too high, the brain may produce too much serotonin, which can lead to inflammation and cognitive problems such as memory loss.

Maintaining balanced blood sugar levels can support optimum brain function, so it is important to have a good understanding of your blood glucose.


Diabetes and The Brain

Diabetes is a condition which means the body can’t move glucose from the bloodstream into the cells due to either a lack of insulin or cells that have stopped responding to insulin. When the glucose cannot enter the cells, it accumulates in the bloodstream, leading to hyperglycaemia or high blood sugar.

When diabetes is caused by problems related to the action of insulin, this is treated by taking insulin and measuring blood sugar regularly. Sometimes the insulin taken works to deplete all of the glucose in the bloodstream, leading to hypoglycaemia or low blood sugar.

People with diabetes can struggle with poor concentration, mood swings and memory problems when blood sugar is too high or too low.

High Blood Glucose and Concentration

High blood glucose can affect the links between regions of the brain, or functional connectivity, leading to difficulties in cognitive processes such as language, decision-making and memory. The impact of hyperglycaemia on brain matter and blood flow in the brain over time has been linked to vascular dementia when it is severe. As such, managing blood glucose is highly important for long-term brain health.

Low Blood Glucose and Concentration

Low blood sugar means that brain cells don’t have the resources to create energy, so it can be difficult to concentrate. It can also cause

  • Fatigue
  • Brain fog
  • Headaches

If you take too much insulin for the amount of food you’re eating, skip meals or have done an intense workout, blood glucose can drop quickly, having an effect on your brain and body.


How to Use Glucose for Mental Focus

Our brains use a huge amount of energy to complete complicated tasks. This energy is made from glucose, so it stands to reason that low blood sugar has an impact on brain function.

There is evidence linking increased blood glucose levels with improved memory and attention. In a 1994 clinical trial, researchers measured the change in performance in a group before and after a glucose drink. The control group were given a placebo. The findings showed that ‘the ability to perform the most cognitively demanding sub-test was selectively enhanced if blood glucose levels were increasing prior to starting the test’ and working memory performance ‘was greater if a glucose drink had been consumed’.

These results are part of a body of evidence that suggests taking fast-acting glucose a few minutes before a task that is cognitively demanding can help improve your attention. You can choose chewable glucose tablets or flavoured glucose drinks depending on your preference and the amount of glucose you need.