Caffeine – how much is too much?

Friday, September 17, 2021


What’s the deal with caffeine? Is coffee good for us or bad for us? What about tea? Soft drink? And doesn’t chocolate have caffeine too?

I love coffee and I’ll admit to a caffeine addiction – evidenced by the headache that takes hold if I haven’t had a coffee by 10am. I generally limit myself to 2 coffees a day; occasionally I sneak in a third, but it has to be before 2.00pm or I’ll struggle to get to sleep.

Caffeine is a popular stimulant drug, found in coffee, tea, energy drinks, soft drink, chocolate and more. It comes from a range of plants, from their seeds, leaves or nuts; different plants and plant parts are used for different versions of caffeine.

How does caffeine work?

Caffeine is a nervous system stimulant. It reduces the impact of our body’s sleep messages and increases the activity of other messages moving between our brain and our body. Generally, caffeine makes us feel more alert, improves our attention, concentration and energy. However, too much caffeine can cause anxiety, nervousness and nausea. Some people are more sensitive to the effects of caffeine and notice symptoms such as these after only a small amount; others can have 5 or 6 coffees a day and barely notice the effect. Caffeine can also negatively impact our sleep – increasing the time taken to fall asleep, reducing how long we stay asleep and impacting our sleep quality.

How much is too much caffeine? Is it safe for kids and teenagers?

Guidelines suggest adults can safely tolerate around 400mg of caffeine per day (around 3 – 4 espresso shots).

Children should limit their intake to around 100mg per day, while teenagers can use 2.5mg per kilogram of body weight as a guide – so a 60kg teenager could have 150mg per day (around 1.5 coffees).

What about energy drinks?

Energy drinks are popular among teenagers, and often have high levels of caffeine – they can contain up to 200mg in one can. Herbs such are guarana are sometimes added to energy drinks, enhancing the effects of caffeine. Consequently, energy drinks can cause a sudden increase in caffeine entering the bloodstream. Too much caffeine, too quickly, can lead to heart palpitations, tremors, agitation and stomach upsets. Caffeine overdose may cause heart problems, seizures and even death.

Excess caffeine intake amongst teenagers has also been linked with risk-taking, disruptive behaviour and increased alcohol consumption. When energy drinks are mixed with alcohol, the caffeine and sugar of the energy drink can mask the effect of alcohol, meaning it’s easy to drink more alcohol than intended. Sleep, already disrupted by caffeine, is further disrupted by alcohol, often resulting in a cycle of needing caffeine to stay alert during the day, resulting in poorer sleep, followed by needing more caffeine the next day and so on.

I don’t often suggest giving up caffeine, given coffee is one of my favourite beverages. However, if you suffer from anxiety, panic attacks, insomnia and heartburn, it’s worth reducing your caffeine intake, as all these conditions may be worsened by excess caffeine.

Be aware of the amount of caffeine you are having, especially if you choose energy drinks (personally I recommend avoiding energy drinks altogether; too high in sugar and the caffeine content is too variable). If you are choosing energy drinks, don’t mix them with alcohol.

If you have children and teenagers consuming caffeine, check in with them as to how much they are having. Ask them how it makes them feel. If needed, work with them to reduce their intake. Most importantly, have an open and honest conversation about the risks associated with combining energy drinks and alcohol.

Develop a positive relationship with food