What's REALLY in your favourite energy drink? The harmful ingredients to avoid, and the ones nutritionists say are OK

The Irish Sun

27-04-2025

WHETHER we need a 3pm pick-me-up or we're gearing up for a tough workout, many of us reach for an energy drink.
But before you crack open your next can, you should know they come with several serious health risks.
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Energy drinks have been linked to everything from anxiety to heart issues
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Scientists have linked the
Research has also found them to make
And a study by Newcastle University even suggested they put children and young people at increased risk of drug taking, violence and
Despite these warnings, the UK energy and sports drink market is worth around £3.1billion, with under-18s guzzling more cans than those in any other European country.
READ MORE ON ENERGY DRINKS
But are all
Raquel Britzke, a nutritionist at Doctify, tells Sun Health: 'They can have a place if used occasionally and thoughtfully, like before a long drive or a workout.
'But the issue with energy drinks is when they're used daily, or worse, multiple times a day.
'I see clients all the time who rely on them to get through the day, which usually signals something else - such as poor sleep, high stress and not enough nourishment from food.'
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If you're going to have an
'Drinking more than that and you risk poor sleep, anxiety, jitteriness, headaches or even heart palpitations,' Raquel adds.
The dangers of energy drinks
'Long term, it can impact blood pressure, blood sugar and overall stress on the body.'
While some energy drinks contain various 'healthy' ingredients, many do not.
From high doses of caffeine to health-harming preservatives, these are the ones to look out for…
CAFFEINE
CAFFEINE is a natural stimulant, and probably why you reach for an energy drink in the first place.
It increases the activity of the brain and central nervous system, helping you to stay alert.
Around 400 milligrams (mg) in separate sittings is considered safe for most adults, according to the European Food Safety Authority.
A large cup of coffee contains around 80mg, but Lucia Stansbie, nutritional therapist and founder of
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The energy and sports drink market is worth around £3.1billion in the UK
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'Too much caffeine can trigger the nervous system, increasing agitation and anxiety,' she says.
'Consuming this during the day can also impact sleep quality, as well as having a dehydrating effect because caffeine is a diuretic.'
Raquel says it's best to consume a maximum of 150mg of caffeine per drink.
Do one better and look for caffeine from natural sources.
'Caffeine from sources such as green tea or yerba matcha is usually better tolerated, and often paired with other beneficial compounds such as L-theanine (in green tea), which has a calming effect and reduces the jittery impact,' she says.
'But it's still caffeine, so the dose matters more than the source.'
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SUGAR
AS well as the caffeine, some energy drinks pack in serious amounts of sugar.
'An average can contains 20g to 50g of sugar,' says Lucia. 'For context, a doughnut contains around 20g.'
But what's the danger?
'Sugar can spike your blood sugar, which is then followed by a crash that leaves you feeling even more tired and craving more sugar or caffeine,' says Raquel.
There is plenty of research demonstrating just how harmful sugar can be.
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Some energy drinks contain up to 55g of sugar per can
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A review in the journal Nutrients, for example, found that people who drank high amounts of sugar-sweetened drinks were more prone to weight gain.
They also had a higher risk of obesity,
A separate study by the University of Washington found women who consumed more than one sugary drink per day were
The NHS recommends no more than 30g of added sugar a day for adults.
Check the label of your energy drink, as sugar comes under various names, such as sucrose, high fructose corn syrup and glucose.
'If your energy drink has more than 10g to 15g of sugar per serving, it is to be considered a high sugar drink which is best not to consume regularly,' says Lucia.
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ARTIFICIAL SWEETENERS
IT'S not uncommon to see artificial sweeteners added to energy drinks.
Many of the zero sugar varieties get their super sweet taste from ingredients like aspartame, sucralose and acesulfame K.
Although they are lower in calories, it doesn't mean they are healthy.
In fact, artificial
Research published in the journal Cureus concluded they can negatively impact your gut, brain and heart.
Scientists at the Karolinska Institute in Sweden found aspartame may trigger insulin spikes and a build-up of fatty plaques in the arteries, which can increase the risk of heart attack and stroke.
A separate study, published in Arteriosclerosis, Thrombosis and Vascular Biology, linked erythritol (E968) to an increased risk of blood clots.
And neotame was found to damage the lining of the intestine, which could lead to
It doesn't matter if a drink features beneficial ingredients - if it is very high in sugar, I would get the same nutrients from food sources
Lucia Stansbie
Nutritional therapist
Lucia says that for her, the most problematic artificial
'They are linked to disruption of the gut microbiome (the bacteria that live within your gut), headaches and metabolic dysfunction,' she adds.
Better alternatives to look out for in your energy drinks, she says, are steve and monk fruit, both of which are natural.
'The sweetener erythritol sits in the middle,' Lucia says.
'It's not totally bad but it can cause gastric distress in excessive quantities.
'People suffering from diabetes and pre-diabetes should be particularly careful with sweeteners and the 'zero sugar' labels as they can still impact insulin metabolism.'
She adds that those with specific neurological sensitivities such as ADHD or chronic
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TAURINE
YOU might see '
Well it is one of 20 amino acids, which are the building blocks of protein.
We naturally make taurine and also get it from foods such as meat.
'On its own, taurine is not usually an issue, and may even support heart and brain health,' says Raquel.
'But when combined with high caffeine and other stimulants, it's a lot for the nervous system to handle, especially in large quantities or for younger people.'
Lucia adds: 'Quantities above 3,000mg can cause vomiting, nausea, headaches, stomach pain and nervous system overstimulation.
'Consider that a Red Bull contains 1,000mg of taurine and that its stimulant effects are enhanced by caffeine.'
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COLOURS AND PRESERVATIVES
EVER wondered why your energy drink is so brightly coloured?
It might be down to artificial colourings, such as E102 (yellow), E129 (red) and E133 (blue).
'These are linked to hyperactivity, allergies and potentially neurotoxicity,' Lucia says.
'I would check for healthier alternatives like natural colourings from beet juice, spirulina or turmeric.'
A 2004 analysis of 15 studies concluded that 'widely distributed' artificial food dyes can increase hyperactivity in kids.
Further research by scientists at Virginia Commonwealth University found animals given high doses of E132 (blue 2) had significantly more
And a study published in Toxicology and Applied Pharmacology found male rats given E127 (red 3) had an increased risk of thyroid tumours.
These tests were done on animals, and further research is needed on the potential dangers for humans.
However, products containing the following artificial colours must carry a warning on the packaging in the UK:
Sunset yellow FCF (E110)
Quinoline yellow (E104)
Carmoisine (E122)
Allura red (E129)
Tartrazine (E102)
Ponceau 4R (E124)
This will say: 'May have an adverse effect on activity and attention in children.'
As for preservatives, which are added to energy drinks to help them last longer, Raquel says sodium benzoate can cause issues for some people, 'especially when combined with certain vitamins like C'.
Research published in the Scientific World Journal found that the higher the concentration of sodium benzoate, the more free radicals are created.
These can damage your cells, increasing your risk of certain diseases such as heart disease and Alzheimer's, scientists say.
Where possible, choose an energy drink with minimal preservatives.
Citric acid or vitamin C are better options, Lucia says.
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THE 'GOOD' INGREDIENTS TO LOOK FOR
ALTHOUGH there are lots of ingredients to be wary of, there are also plenty that can offer health benefits.
'Adaptogens (natural substances that help the body adapt to stress) like ashwagandha can help mitigate the caffeine spike,' says Lucia.
Raquel adds: 'Electrolytes such as magnesium, potassium, and sodium are great if you're sweating a lot or need hydration support, and B vitamins support energy production.'
Vitamin C is also great as it supports the immune system and helps to maintain healthy skin and bones.
But, regardless of any 'healthy' ingredients, Lucia warns: 'I will always be mindful of the sugar content.
'It doesn't matter if a drink features all the beneficial ingredients above - if it is very high in sugar, I would still discharge it and get the same nutrients from food sources.'
Exactly what a single energy drink can do your body – minute by minute
By Vanessa Chalmers, Assistant Head of Health
YOU may be familiar with the surge in alertness after drinking an energy drink, but there are half a dozen things that
Data from gift site
It was created using information from sources including the UK's National Health Service (NHS), the US Food and Drug Administration (FDA), and energy drink manufacturer Red Bull.
It may make you re-think your habit, and re-assess whether the highs and lows of energy are worth it for a quick hit.
First 10 minutes
That's the time the caffeine begins to enter the bloodstream, causing your
Previous research has looked at the impact of energy drinks on the blood pressure and hearts of young people.
One small
15-45 minutes
This is the time caffeine level peaks, making you feel alert and improving concentration.
30-50 minutes
By now, all of the caffeine has been absorbed and your liver will often react by absorbing more sugar.
1 hour
This is when you are likely to get the 'sugar crash' - when your blood sugar and caffeine level drops - and you may feel tired.
5-6 hours
Roughly five to six hours after consumption your body will have reduced the caffeine content in your bloodstream by 50 per cent.
12 hours
Around 12 hours after finishing an energy drink, the caffeine will be out of most people's bloodstreams, but it does vary due to age and activity.
12-24 hours
If you have been drinking energy drinks regularly, between 12 and 24 hours is the time you'll start to feel withdrawal symptoms.
You may suffer from headaches, irritability and constipation.
7-12 days
Studies have shown this is the time it takes the body to become tolerant of your daily caffeine dosage.
This means if you keep the level the same, you are unlikely to feel any effects at this point.
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Look out for colours, sweeteners and preservatives in energy drinks
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