Caffeine: Is Your Daily Coffee Helping or Harming You?
For many of us, the day doesn’t really begin until we’ve had that first cup of tea or coffee. It might be part of the morning routine, a mid-afternoon pick-me-up or simply an excuse to have five minutes to ourselves.
Caffeine is one of the most widely consumed stimulants in the world. It can help us feel more alert and improve attention, but it can also affect our sleep and cause unpleasant symptoms in some people.
So, how much caffeine are we actually consuming, and when might it start having an effect on us?
What does caffeine actually do?
Caffeine acts on the central nervous system, helping us feel more awake and alert. One of the ways it does this is by blocking the action of adenosine, a chemical messenger that builds up during waking hours and contributes to feelings of sleepiness.
This can make us feel more alert temporarily, but it doesn’t remove our underlying need for sleep. If we’re tired, caffeine may help us feel more awake without fully correcting the effects of insufficient sleep.
Research published in 2025, including a systematic review and meta-analysis of 31 trials involving 1,455 adults, found that caffeine can produce modest improvements in attention and reaction time. However, the effects vary, and more caffeine does not necessarily mean better performance.
How much caffeine are you drinking?
It’s easy to underestimate how much caffeine we consume, particularly when we drink several different types of caffeinated drinks throughout the day.
The amount varies depending on the product, serving size, brewing method and preparation. Coffee bought from a café, for example, can contain considerably more caffeine than a typical cup made at home.
The NHS gives the following approximate amounts:
Drink or food | Approximate caffeine |
Mug of instant coffee | 100 mg |
Mug of tea | 75 mg |
Can of cola (330 ml) | 40 mg |
Energy drink (250 ml) | 80 mg |
Dark chocolate (50 g) | Less than 25 mg |
These are estimates, not fixed amounts. Larger drinks, stronger brews and some branded products may contain substantially more.
How much caffeine is too much?
According to the European Food Safety Authority (EFSA), consuming up to 400 mg of caffeine a day from all sources does not generally raise safety concerns for most healthy, non-pregnant adults.
That is a safety reference level, not a target everyone should aim to reach. Some people notice effects at much lower amounts, particularly if they are sensitive to caffeine, take certain medications or have particular health conditions.
EFSA also notes that a single dose of around 100 mg may affect sleep in some adults, especially when consumed close to bedtime.
In other words, there isn’t one perfect amount for everyone. How you feel, how well you sleep and when you consume caffeine are all worth considering.
Caffeine and sleep: does timing matter?
Sleep is one of the clearest areas in which caffeine can have an unwanted effect.
A systematic review and meta-analysis published in Sleep Medicine Reviews in 2023 examined 24 studies and found that caffeine consumption was associated with less total sleep, taking longer to fall asleep and more time awake during the night.
The size of the effect depends on factors including the dose and timing of caffeine, as well as individual differences. You might be able to enjoy an after-dinner coffee without noticing much difference, while someone else may find that an afternoon cup affects their sleep.
If you struggle to fall asleep, wake frequently during the night or don’t feel refreshed in the morning, it may be worth experimenting with an earlier cut-off time for caffeine.
One practical approach is to reduce or avoid caffeine in the afternoon and evening for a couple of weeks and see whether your sleep changes. There is no single cut-off time that suits everyone.
Can caffeine cause headaches or muscle tension?
This is where the answer becomes a little more nuanced.
Headaches: Caffeine affects people differently. It is included in some headache medicines, but regular caffeine consumption can also lead to withdrawal symptoms when intake is reduced or stopped suddenly. Headache is one of the best-established caffeine withdrawal symptoms.
However, research does not show that ordinary caffeine consumption reliably increases headaches in everyone. If you experience frequent headaches, it may be useful to consider your caffeine intake alongside other factors such as sleep, hydration, stress and medication use.
Muscle tension and aches: Caffeine can cause symptoms such as jitteriness or feeling anxious in some people, which may make them feel more tense. Muscle pain and stiffness have also been reported during caffeine withdrawal. However, there is not strong evidence that everyday caffeine consumption directly causes general neck pain, back pain or joint pain.
If you regularly experience muscular discomfort, it is worth considering the wider picture rather than assuming that coffee is the cause.
Does caffeine have any benefits?
Yes. Caffeine is not inherently bad, and there is no need for everyone to stop drinking tea or coffee.
The evidence supports short-term improvements in alertness and attention. Caffeine is also widely used in sport because it can improve certain aspects of exercise performance in some circumstances, although the response depends on the person, dose and activity.
The important distinction is between a potential benefit and assuming that more is always better. Increasing your intake may bring unwanted effects, particularly if it disrupts your sleep or leaves you feeling anxious or jittery.
Five practical ways to manage your caffeine intake
You don't necessarily need to give up your favourite drink. A few small changes may be enough if caffeine is affecting you.
1. Keep track of what you drink. Include tea, coffee, cola, energy drinks, chocolate and products containing added caffeine. You may be consuming more than you realise.
2. Think about timing. If sleep is a problem, try moving your last caffeinated drink earlier in the day.
3. Experiment with smaller servings. A smaller coffee or a weaker brew may reduce your intake without requiring you to stop altogether.
4. Cut down gradually if needed. Suddenly reducing regular caffeine intake can cause headaches, tiredness, irritability and difficulty concentrating. Gradual reduction can make this easier.
5. Pay attention to your own response. Notice whether caffeine seems to affect your sleep, anxiety, palpitations or headaches. If symptoms persist or concern you, seek appropriate medical advice rather than assuming caffeine is the only explanation.
What about pregnancy and breastfeeding?
Caffeine guidance is more restrictive during pregnancy. The NHS advises limiting intake to no more than 200 mg a day because higher consumption has been associated with an increased risk of pregnancy complications.
During breastfeeding, caffeine can pass into breast milk. The NHS recommends keeping intake to no more than 200 mg a day, particularly because younger babies may be more sensitive to its effects. If your baby seems unusually restless or has difficulty sleeping, it may be worth reviewing your intake with your midwife or health visitor.
For detailed advice, see the NHS pages on caffeine during pregnancy and caffeine while breastfeeding.
So, should you give up your daily coffee?
Not necessarily!
For most healthy adults, moderate caffeine consumption can fit comfortably into a balanced lifestyle. It can help with alertness and attention, but it can also interfere with sleep or cause unwanted symptoms in some people.
Rather than focusing only on how many cups you drink, consider how much caffeine they contain, when you drink them and how you feel afterwards.
If you enjoy your morning coffee and sleep well, there may be no reason to change your routine. But if you're struggling with sleep or notice that caffeine leaves you feeling jittery or uncomfortable, a few small adjustments could be worth trying.
Sometimes, the answer isn't giving up your favourite drink. It's simply finding the balance that works for you.
Looking after your wellbeing
Small everyday habits can make a difference to how we feel, from getting enough sleep to staying hydrated and being mindful of our caffeine intake.
If you're also dealing with persistent aches, pains or stiffness, the team at Exmoor Osteopathy & Sports Injury Clinic in Minehead is here to help.
Or get in touch with our team to find out more.
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