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The impact of nutrition on work performance

Francesca Abalasei
Written by

Francesca Abalasei

Medically reviewed by

Fiona Moncrieff

5 min read
Last updated June 2024

Jump to: Sugar Intake | Irregular Meals | Caffeine | Takeaway message

Nutrition can impact work performance in three key ways:

1) Excessive sugar intake can send our blood sugars on a rollercoaster, impacting concentration and cognitive function
2) Irregular meal patterns can drive us to go for long times without energy leaving us tired and low on energy
3) Caffeine intake impacts the quality of our sleep and consequently affects the ability to think clearly and perform under pressure

Promoting employee well-being should be a top priority for every workplace. In the wake of the Covid-19 pandemic, many employers have identified the impact that employee wellbeing has on both individual performance and overall business outcomes.

A key aspect of any successful employee well-being program is nutrition and addressing the role that diet plays in influencing energy levels, mood, cognitive performance, and productivity.

This article will cover the top three ways that nutrition can impact work performance, including:

1. How sugar starves your brain of energy
2. Why skipping meals leaves us ravenous and unable to concentrate
3. Why being over-reliant on caffeine actually makes you more tired

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1. How sugar starves your brain of energy

It will come as no surprise that our brain depends on glucose as its main source of energy. Therefore, tight regulation of blood glucose levels is critical for brain performance.

Even though the brain only accounts for ~2% of our total body weight, it consumes ~20% of the glucose our body gets from the food we eat. Because of this, the performance of our brain is strongly impacted by our blood glucose levels throughout the day.

Eating foods high in simple sugars, such as biscuits, breakfast cereals, sweets, or fizzy drinks, can cause our blood sugar levels to peak quickly, which is why these foods lead to a short-term energy boost.

However, these foods also cause our blood sugar levels to fall quickly, leaving our brain cells starved of glucose and causing symptoms like lightheadedness, brain fog, and poor concentration.

To counteract this energy slump, we often reach for foods that are high in simple sugars for that same quick-release energy, and so the cycle continues. This pattern of eating affects our ability to think clearly and leaves us feeling tired, unfocused, and irritable.

An easy way to reduce large fluctuations in our blood sugar levels tis to choose foods that contain protein, complex carbohydrates, and healthy fats. So instead of the simple fruit bowl in the office, why not add a jar of peanut butter and some nuts alongside it?

2. Why skipping meals leaves us ravenous and unable to concentrate

We’ve discussed the impact that eating foods high in simple sugars can have on our energy levels and brain function throughout the day.
Another common pitfall that many people make that can have a significant impact on energy levels, mood, and concentration throughout the day is not having a regular meal pattern.

It can be tempting to skip meals when we’re in a rush to get to work or dealing with a project deadline. However, if our brain detects that we’re not eating enough, it will respond by increasing our hunger hormones and heightening our sense of taste and smell.

This makes us more sensitive to food cues, especially from energy-dense foods like chocolate, crisps, sweets, and biscuits.

So skipping a meal or going for long periods without eating drives us to think about and crave food, which can lead to energy-dense food choices and overeating at our next meal.

This is why eating three main meals spaced evenly across the day is one of the best strategies to balance our blood sugar levels and keep our energy levels and concentration consistent.

Ideally, a balanced meal should include:

  • 25% high-fibre carbohydrates
  • 25% protein
  • 50% non-starchy vegetables
  • At least one serving of fat

Aim to have balanced meals that keep you full until your next meal. However, if you have a long break between meals (more than five hours), it’s a good idea to have a healthy snack.

Your employees can also access personalised advice on building the right meals to suit their bodies through our Health Transformation Tool.

3. Why being over-reliant on caffeine actually makes you more tired

Caffeine culture underpins many modern workplaces, with coffee often being used as a tool to help us connect with our colleagues and make it through a busy day.

However, many people don’t realise the impact that the amount and timing of our caffeine intake can have on our cognitive function, energy levels, and mood.
Caffeine is a natural stimulant that activates our central nervous system to improve mental performance and increase alertness. This is why we often feel that ‘boost’ or caffeine ‘buzz’ after a coffee.

However, caffeine can impact our sleep quality because it blocks the effects of hormones that make us feel sleepy in the evening. This can create a cycle where the caffeine we drink throughout the day leads to poor-quality sleep, which means we feel tired and low in energy the following day, and therefore reach for more caffeine to help us get through.

For this reason, it can be beneficial to gradually reduce your caffeine intake and monitor the positive benefits this has on your sleep quality and overall energy levels.

Here are some top tips on how to optimise caffeine intake:
1. Have your first coffee or tea an hour or more after you wake up
2. Limit caffeinated drinks to the morning
3. Swap to decaffeinated tea or coffee in the afternoon and evening
4. Experiment with herbal teas, most of which are free from caffeine

Takeaway message

There are many factors that can impact employee wellbeing and productivity, a key one of which is nutrition. This includes making the right food choices, having a regular meal pattern, and being mindful of caffeine intake to promote consistent energy levels throughout the day.

We understand it can be difficult as an employer to directly impact the food choices and dietary habits of your workforce. While there are some changes you can implement such as offering healthy snacks and encouraging employees to take a lunch break away from their desks it can be challenging to address eating habits at an individual level.

This is why we’ve designed a Health Transformation Tool designed to empower each employee to take control of their nutrition and wellbeing.

Through this interactive tool, every team member will have access to a registered nutritionist who will provide personalised recommendations and expert guidance to optimise employee wellbeing. Research shows that investing in employee health and wellbeing has tangible impacts on business outcomes, employee engagement, and retention, creating a happier workforce where everyone can thrive.

Want to offer your employees the personalised health solution they deserve? Head over here.

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