Should teenagers drink coffee and energy drinks?

From flat whites to energy drinks, Australian teenagers drink a surprising amount of caffeine. Here’s how it affects their health.

On average, 75% of Australians  enjoy at least 1 cup of coffee a day. Picking up a coffee from your local cafe is a daily routine for many, so it’s no great surprise that seeing teenagers drink coffee is a more common occurrence, too.

Research suggests 15% of Australian adolescents are regularly drinking coffee, and teenagers aged 14–17 consume an average of 5.5 cups of caffeinated tea a week.

But caffeine intake isn’t limited to tea and coffee. A recent survey found 8% of Australian students in years eight to 11 consume energy drinks weekly.

The effects of caffeine on teenagers’ health

How does caffeine intake affect teenagers’ minds and bodies, and should we be worried? As clinical psychologist Gemma Cribb explains: “Caffeine acts as a central nervous system stimulant to increase alertness and make you feel less worn out.”

Caffeine keeps you awake by blocking a chemical process in the brain that causes drowsiness.

While feeling less tired may seem beneficial for overworked adults, the effects of caffeine in teenagers can be far reaching. Because of their smaller body weight (on average), caffeine has more than twice the impact on children than it does on adults.

This means children and young adolescents are more susceptible to caffeine-related symptoms like anxiety, insomnia and nervousness.

Additionally, studies have suggested that the developing teen brain is more susceptible to stress and addiction – and it has been suggested that regular caffeine consumption can lead to dependence.

In the longer term, developing a habit of drinking a lot of coffee could be harmful to heart health. A study by the University of South Australia found drinking six or more coffees a day increases your risk of heart disease by up to 22%.

Caffeine, teenagers and sleep

Teens need an average of 8–10 hours sleep a night, but most are only getting 6.5–7.5 hours or less. This can impact concentration, mood and academic performance.

Plus, caffeine can make things worse. Research reveals young people who drink energy drinks at least once a week are twice as likely to get less than the recommended amount of sleep on school nights than those who don’t.

Studies show caffeine consumption can affect a teenager’s concentration and ability to sleep, which in turn may slow the maturing process of their brains.

“During adolescence, the brain has the most neural connections it will ever have in your life,” Gemma explains. “Caffeine (with its effects on sleep) will disrupt your brain's ability to form these connections.”

Not getting enough sleep may also worsen the impact of mental health problems among young people brought on by the pandemic. There’s a close relationship between sleep and mental health, with poor sleep a contributor to the onset and worsening of mental health problems.

Getting enough sleep, on the other hand, can have a protective effect on mental health.

Coffee vs energy drinks for teens

For Australian teenagers, energy drinks are a growing area of concern due to high levels of both caffeine and sugar. Some energy drinks contain up to 21 teaspoons of sugar and as much as 320mg of caffeine (equivalent to 2–3 cups of coffee).

What’s more, Cancer Council research found that one in six Australian teenage boys drink at least 52L of soft drink every year.

The mix of caffeine and sugar can also affect mood, according to dietitian Susie Burrell. She says that after drinking an energy drink, teenagers can “experience a ‘down’ period about 30–40 minutes afterwards”, which can lead to poor health choices.

This is backed up by Australian research that found teenagers who drink soft drinks and energy drinks are twice as likely to also be consuming more junk food.

“Consuming too much caffeine can stop a teenager from getting adequate nutrition,” says Gemma. “Especially if they choose to drink coffee and soda rather than consuming more nutrient-dense foods, for example.”

The pressure to perform

The rise in teenagers’ caffeine consumption could easily be put down to marketing and popular culture embracing coffee and performance drinks, but Gemma believes it might be societal pressures that make caffeine more attractive to teenagers.

“There’s a lot of pressure on teenagers to perform,” she says. “They feel the need to keep up with social media, their homework and the fast pace of modern life in general. And they see caffeine as giving them an edge.”

At what age is caffeine or coffee safe for teenagers?

Susie advises that adolescents under 14 should avoid caffeine where possible, and teenagers between 14 and 17 years of age should limit their intake to 100mg or less a day.

“That’s equivalent to a small milky coffee (60mg), or a couple of cups of tea (30mg each), or some [dark] chocolate (26mg/40g) a day,” she says.

It’s best to steer clear of energy drinks during adolescence. “Some teenagers are drinking four large coffees, an energy drink plus a cola drink in a day,” Susie says. “That could equate to as much as 500–600mg of caffeine. That’s why, as a rule, energy drinks that are high in sugar and stimulants should be avoided altogether.”

Words by Lucy Cousins and Angela Tufvesson
Updated August 2022