Feeling buzzed? How much caffeine is too much?

Monday, 3 September 2018

For many of us the humble cuppa is an important part of our daily routine. Whether it be the daily office coffee run or a cup of tea and a long chat with a friend, caffeinated drinks are an important and common part of our everyday lives.

Caffeine is the most widely consumed stimulant and has been consumed for thousands of years, starting with the first teas.

Today we find caffeine in beverages such as tea, coffee, cola, energy drinks and also foods such as chocolate or cacao. Cola, energy drinks and chocolate are all considered sometimes foods rather than everyday foods, but tea and coffee on the other hand can be safely considered to be a healthy everyday choice.

Caffeine consumption has been extensively studied, and the good news is when consumed in moderation there is no evidence of adverse health effects.

In fact, caffeine consumption can have several benefits including enhanced mental alertness and cognitive functioning, as well as improved sporting performance.

However, some individuals are more sensitive to caffeine than others and should be aware of the common negative side effects of consuming too much caffeine. These can include jitteriness, nervousness, anxiety, gastrointestinal upset, increased heart rate and insomnia or sleep disturbance. While it is uncommon and unlikely to occur from food and drink, it is important to note that caffeine can be toxic in high doses, such as when excessively consuming caffeine tablets or capsules.

Moderate intake is typically defined as ≤400 mg/day for the average adult, ≤300 mg/day during pregnancy and lactation and ≤2.5 mg/kg/day for children and adolescents. With the consumption of caffeinated drinks increasing in children and teens there is evidence of a link between increased anxiety when this limit is exceeded.

While it’s probably not wise to consume tea or coffee completely in place of water, contrary to popular myth, it does actually count towards your daily fluid intake, with the hydrating effect of the tea or coffee outweighing the small diuretic effect of the caffeine.

For keen coffee and tea drinkers the other consideration is how many extra calories and sugar your daily ritual may be adding. It’s best to avoid added sugar and syrups and to consider how many extra milk based drinks you are consuming a day. For those who are concerned about weight stick to a small milk based coffee per day and opt for black or a piccolo after that to limit the amount of liquid calories you are consuming.

Caffeine content of some food and drinks:

Food Caffeine content
Espresso 145 mg/50 mL cup
Formulated caffeinated beverages or ‘ Energy’ Drinks 80 mg/250 mL can
Instant coffee (1 teaspoon/cup) 80 mg/250 mL cup
Black tea 50 mg/250 mL cup
Coca Cola 48.75 mg/375 mL can
Milk chocolate 10 mg/50g bar


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