Are you consuming too much caffeine?

Coffee, tea and chocolate are staples of any teacher’s kitchen, but how are they affecting you in the classroom?
28th May 2019, 6:04am


Are you consuming too much caffeine?

It’s Monday morning, the sun is streaming through the curtain and your alarm has been going off for 10 minutes. You gather what little energy you have to drag yourself from your bed and get ready for work. Your mission starts, as usual, with a coffee.

Caffeinated substances prepare many of us for the day ahead: tired parents, stressed students and overworked teachers in particular. But while caffeine may seem like a source of pep, frequent, excessive intake can have damaging neurological, physical and emotional affects - both short and long term. 

Dr Sarah Brewer is a medical nutritionist and author of more than 60 health books. Generally, she believes that the good effects associated with coffee consumption outweigh the bad. But she says excess caffeine is definitely harmful.

So how much is too much? Are you in the “too much” group? And what might too much be doing to you? 

Meet Alysha, Conor and Sue. These teachers have many things in common, but one thing that differs is how much caffeine they consume. How close your routine matches each of them will give you a good idea of whether you need to cut back on the coffee (or tea, or - horror - chocolate). 


Alysha has two children and is a primary school teacher. For her, a good day starts with a cup of tea, as she rushes around, getting her kids ready for school. 

For breakfast, she eats a slice of toast in the car and washes it down with a cup of tea at her desk.

At breaktime, she checks her emails and drinks from the refillable bottle of water she carries with her throughout the day.

Over lunchtime, she tries to get through some marking, grabbing what food she can from the canteen. It’s usually not much more than a bag of crisps and an apple. 

After school, she meets a student and their parent. She offers both a drink and has a cup of coffee herself. 

Back home, and once the kids are in bed, she pours herself a cup of hot chocolate and finishes tomorrow’s lesson plans.

Total caffeine intake: approx 125.9mg 

Dr Brewer’s view:
Alysha’s coffee intake is under the daily caffeine allowance of 400mg. This amount should have “no consequences for healthy adults”, says Dr Brewer. However, the hot chocolate that Alysha pours herself before she goes to bed could be detrimental to the quality of sleep she gets.

“Caffeine can interrupt the adenosine receptors in the brain, which encourages the relaxing response our body needs to wind down,” Dr Brewer explains. She adds that if you are particularly sensitive to caffeine, perhaps avoid drinking it from late afternoon onwards.  


Conor is a newly qualified teacher in the Midlands. He works in a secondary school and, although he enjoys the job, is feeling pretty stressed with the workload. 

Conor is a commuter, he doesn’t have time for breakfast; instead, he grabs a coffee on the train to work.

When he finally arrives, he’s ready for his second cup of coffee, drinking it quickly before his first lesson. 

At breaktime, he tries to find his mentor and manages to swig another cup of coffee while he is at it. 

Conor’s mum still makes his lunch most days. His routine meal is a can of Coke, a sandwich, a chocolate bar and a packet of crisps. 

After school, everything is such a rush that he has no time to grab a drink or anything to eat. He gets his jobs done then heads to the gym. 

After an hour of working out, he’ll pick up a protein bar and a Lucozade energy drink from the vending machine.

He grabs a light dinner and soon heads to bed. 

Total caffeine intake: approx 387.4mg 

Dr Brewer’s view:
Conor starting his day with a coffee isn’t the best thing. Between 8am and 9am, your body is naturally flooded with cortisol, a stress hormone that mobilises the energy from your sleep.

His breaktime coffee is better timed, says Dr Brewer, as “10am is when the cortisol peak has fallen, so this is when an energy boost would be most effective”.

However, Conor’s caffeine habits extend beyond coffee and tea. His can of Coke and chocolate bar at lunchtime, and the evening gym snacks, are classic examples of how easy it is to consume caffeine when you don’t realise it.

By reducing his intake, Conor would quickly see some positive effects, says Dr Brewer. 

“He’d feel more energised, less irritable, think more clearly… and he may even lose weight,” she explains. 


Sue has been at her school for 20 years. She is currently a senior leader, but a deputy head position has opened up and she’s working extra hard to make sure she’s in line for the job. 

Sue walks into work and, on her way in, picks up a coffee and pain au chocolat. When she gets into school, she calls a subject meeting and has a cup of tea. 

During her free period, she pours herself a coffee and, together with a colleague, goes through the plans for the upcoming sports day. 

At breaktime, Sue sits down with the school’s drama teacher, she’s volunteered to help with the summer play, and they discuss the cast list over tea. 

Lunch is a sandwich washed down with a Diet Coke, while she does some marking. 

When the end of the day bell rings, Sue heads out for bus duty with a cup of tea in hand. By the time she reaches the governor’s meeting, she is ready for a coffee. 

Before dinner, she has tea and finishes marking. After dinner, she treats herself to chocolate cake and prepares tomorrow’s lessons.

Total caffeine: approx 546.7mg

Dr Brewer’s view:
Sue is regularly consuming more than 400mg of caffeine. Because of this, it is likely that she has a caffeine addiction.

As a regular caffeine user, it is likely that Sue’s body will frequently display an increase in heart palpitations; this is due to the caffeine mimicking the effects of stress in the body; these are a few of the warning signs that it’s time to break the addiction. 

Kicking the habit 

Caffeine has addictive properties. Regular users may find that, over time, they may need a higher intake of caffeine to feel the effects; this is known as caffeine-dependence syndrome. 

“If you are reliant on a regular caffeine fix then, as a result, the number of brain receptors that respond to other stimulant neurotransmitters may decrease if they are less needed,” says Dr Brewer.

If you’re struggling to quit caffeine, she suggests cutting back on caffeine slowly rather than an abrupt stop.

Essentially, if you were to suddenly stop “using” caffeine, your adenosine receptors would be deprived of their usual caffeine “fix”, and your other coping mechanisms would be unable to adapt quickly enough to prevent symptoms of withdrawal, such as headache, irritability, fatigue and lethargy. 

Here are Dr Brewer’s tips to kick the habit: 

  1. Brew your drinks for a shorter length of time or add fewer granules/tea leaves.
  2. Change caffeinated drinks for decaffeinated versions. 
  3. Swap one cup of tea per day for a herbal blend, such as chamomile. 
  4. Take a herbal supplement, such as mountain ginseng, which can improve alertness, stamina and sleep quality.

Ella Jackson is a member of the Tes editorial team

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