Energy drinks have been around for a long time. In fact, it has been approximately 72 years since the first energy drink was introduced in the US. Dr Enuf (weird name, I know) was introduced in 1949. However, the ‘energy drink era’ didn’t officially kick off until around 1962 when a Japanese company named Taishe released ‘Lipovitamin D’ (Chatterjee and Abraham, 2019). It was marketed as a medicinal tonic and contained had added taurine and niacin to enhance the improvement of energy and concentration. The well-known Red Bull was later introduced in Australia in 19897 and the US in 1997 (Manchester et al., 2017) . Today there are over 500 different types of energy drinks and energy shots available (Seifert et al., 2011).
Energy drinks are promoted for their ‘claimed’ beneficial effect on physical and mental alertness. They are commonly used by athletes due to their high sugar content, but it’s become more and more common for non-athletes to drink large amount. Especially teenagers and young adults. However, data has shown that consuming large volumes of energy drinks can be potential harmful because of increased cardiac workload and decreased blood flow to the brain which has been observed in multiple studies on the health effects of energy drinks (Grasser et al., 2014).
Energy drinks don’t just contain a lot of sugar because you can get sugar free versions. They also contain caffeine amongst other chemical compounds. Most energy drinks contain like if not more caffeine than a cup of strong coffee.
The European Food Safety Authority (EFSA) conducted a study that looked at energy drink consumption (Cikaric, 2021). They found that a whopping 68% of teenagers (aged 10 -18 years old), 30% of adults and 18% of children under 10 consumed energy drinks daily. The average daily consumption from children under 10 was about 500ml (that’s 1 can) and the average daily consumption for teenagers was 2 litres (that’s 4 500ml cans). I don’t know about you, but those numbers are scary! Especially when you see all the health implications that come with energy drink consumption.
First let’s look at caffeine. Caffeine is the worlds most popular drug. Yes, caffeine is a drug. It increases energy metabolism in the brain, but, at the same time it causes vasoconstriction meaning it reduces blood flow to the brain…. you don’t need a medical degree to know that that’s not good. It basically makes your body work harder while reducing blood flow.
It is also a stress stimulator meaning it increases levels of the stress hormone cortisol. Cortisol is the ‘fight or flight’ hormone and our body is not equipped to deal with increased levels of cortisol for long periods of time. Caffeine also increases levels of anxiety and interferes with sleep. Caffeine does improve alertness and if you’re feeling tried and need a pick me up it might help, but in the long run you’d really be better figuring out why you’re so tired. Maybe getting that pick me up from some healthy carbs? Taking a nap? Both these options have zero health implications…
Now let’s look at why energy drinks are so harmful to our health.
• Cardiovascular – So the health scares that seem to be sending people to A&E are heart issues. Energy drinks increase heartrate and arterial blood pressure about 1 hour after consumption (Grasser et al., 2014). This is attributed to the caffeine content. Recent reports have demonstrated a strong relationship between energy drink overconsumption and arterial dilatation, aneurysm formation, dissection, and rupture of large arteries (Alsunni, 2015).

• Neurological and Psychological effect – Studies have shown that more than 200mg of caffeine causes caffeine intoxication (like you’re drunk on caffeine instead of being drink on alcohol). Caffeine intoxication can lead to insomnia, anxiety, Gastrointestinal upsets, muscle twitching, restlessness, periods of inexhaustibility and acute and chronic headaches. That a long enough list for you??? There have actually been four caffeine induced psychiatric disorders that are recognised by the Diagnostic and Statistical Manual of Mental Health Disorders (Jones and Fernyhough, 2009). These are;
Caffeine intoxication
Caffeine induced anxiety
Caffeine induced sleep disorder
Caffeine related disorder
Caffeine intake and violent behaviours in young teenagers has also been linked. Several reports state that energy drinks may contribute to ischemic stroke and lead to epileptic seizures. Also note that over 300mg of caffeine can lead to hallucinations. This could be since cortisol (the stress hormone I mentioned earlier) enhances the psychological effect of stress resulting in a greater tendency for hallucinations.

• Gastrointestinal and Metabolic effects – These energy drinks usually contain large amount of sugar, and a lot of calories. Remember calories = energy. So, if you aren’t burning off that excess energy then it’s stored in your body as fat. It is thought that high sugar drinks are one of the main causes of childhood and adolescent obesity worldwide (WHO, 2019). Monosaccharides sucrose, glucose and high fructose corn syrup are the main energy sources you’ll find in energy drinks and it’s been found that they may have negative effects on intestinal bacteria activity, diversity, and gene expression. This results in an increase risk of obesity and Irritable Bowel Syndrome (IBS) (Greenblum et al., 2012).
Large volumes of caffeine can also reduce insulin sensitivity leading to a 5.8% increase in the amount of insulin required for every mgkg of caffeine (Lee et al., 2005). Basically, the more caffeine you consume the less effective the insulin your body produces becomes, meaning it needs to produce more and more.
There was also a case where a young woman presented to A&E with jaundice, abdominal pain and highly elevated liver enzymes after consuming a large volume of energy drinks (Vivekanandarajah et al., 2011). The same thing was also reported in a 34 year old male (Huang et al., 2014).

• Renal – Caffeine is a diuretic, meaning it makes you lose more water through urination (Alsunni, 2015). These means energy drinks are not great at hydrating you. They should be avoided during prolonged periods of physical activity, especially in a hot environment as they could cause dehydration. Caffeine also promoted the excretion of sodium in the urine (natriuresis), which effects the plasma volume of the blood. This can cause adverse cardiac performance during exercise and can lead to sodium imbalance; both can be life-threatening.

• Dental – Well this one is obvious. What happens when you consume a high sugar and a low pH (acidic) drink? Dental erosion, your enamel corrodes, also cavities and other dental issues are caused by energy drinks (as well as other soft drinks).

Some popular energy drinks include Red Bull, Monster, Rockstar, CELCIUS, 5-hour energy shots, but like I said there is a wide range of energy drinks out there to choose from. Red Bull is probably the most popular and most well studies energy drink to date.
What’s the difference between an energy drink like Red Bull and a soft drink like Coke? Both contain a lot of sugar, and both are caffeinated (355ml of coke contains 114mg of caffeine, same as a 500ml can of Red Bull). However, you don’t hear of people being rushed to A&E for irregular heartbeats or heart attacks caused by drinking too much Coke. Yeah over time the extra calories from the sugar may catch up with you, and your teeth won’t thank you, but drinking a litre of coke in 24 hours aside from maybe making you feel a bit unwell won’t put you in the hospital…or in a coffin. There are four ingredients that are in pretty much most energy drinks. Sugar, caffeine, guarana, Taurine and Ginseng. This would make one think that it isn’t just the caffeine and the sugar causing these health issues.
This theory was put to the test in one study where they split 18 young healthy adults with no previous health conditions and who weren’t on any medication. One group drank 946ml of energy drink containing 320mg of caffeine daily for six days. The other group was given a placebo of sugared water with the same 320mg of caffeine added. The group who received the energy drink had a significantly higher QT interval prolongation and systolic blood pressure than the control group.
The QT interval is graph on an ECG and an increased QT interval for a prolonged period is a recognised marker for an increased risk for fatal arrythmias…yes…fatal as in you could die. Prolongation of QT interval by 60 ms from baseline is a marker for life threatening arrythmias. The energy drink caused a prolongation of around 10 ms2 hours after consuming the energy drink. This doesn’t seem too bad, but actual medications that were showing promise have been pulled from the market for safety reasons for showing a 5 to 10 ms QT interval prolongation.
Another much larger meta-analysis study done on one million people showed that an increase of 3 to 4mm Hg in Systolic blood pressure leads to a 20% increased risk of stroke mortality and 12% increased risk of ischemic heart disease mortality (Shah et al., 2016). Pretty much all energy drinks studies showed an increase in Systolic Blood Pressure by 3 or more mm Hg.
Another scary thing about energy drinks is the amount of people who consume them with alcohol. Energy drinks mask thee sign of alcohol inebriation. So when you’d normally be what we’d refer to as ‘blind drunk’ barely able to stand etc, with energy drink you wouldn’t start feeling like this until you’ve consumed a dangerous amount of alcohol that would cause alcohol poisoning. People who regularly consume energy drinks are also more likely to drink large amounts of sugary drinks, smoke, binge drink, smoke marijuana, abuse steroids and other drugs (Ali et al., 2015).
In 2019 the FDA stated that 34 deaths caused by overconsumption of energy drinks occurred. There has also been a large increase in the number of people hospitalised or rushed to A&E due to either consuming energy drinks with alcohol, or just over consuming energy drinks. You’d think with all the evidence showing the any life-threatening health risk the energy drinks because they’d at least be regulated in some way? Maybe banned for under 18’s? To date England has banned the sale of energy drinks to under 16’s. Lithuania and Latvia have also banned the sale of energy drinks to minors. France, Denmark, Norway, and Uruguay outlawed Red Bull outright because of concerns over taurine, but they were forced to lift the ban in 2008 as EU law states that a product made or sold in other EU countries cannot be banned unless a health risk is proven. In 2009 Germany banned the sale of Red Bull cola when it found trace amounts of cocaine in it. Red Bull claimed they only used the cocoa leaves for flavour and any active cocaine was removed.
The FDA imposes a limit of 71mg of caffeine per 12floz in soft drinks, but energy drink claim to be ‘natural dietary supplements’ so they’re regulated to the same extent as other health supplements like protein powders, which isn’t very much to be honest.
Energy drinks are advertised at athletes claiming to improve athletic performance, but there is actually very little solid evidence backing up these claims. In fact, one study showed that aside from having no ergogenic potential for performance enhancement from Red Bull when compared to drinking sugared water with caffeine. Red Bull also caused increased levels of inflammation which would hinder athletic performance (Phillips et al., 2014).
I honestly try to be open minded when I research anything. Put my true feelings aside. My true feeling on energy drinks have always been that they should be banned outright for everybody and after reading all the horror stories and studies carried out backing up these horror stories my opinion has not changed one little bit.
I understand if you’re tired, maybe you work shifts, you need a quick boost of energy. Maybe you don’t have time to have a quick nap or to sit down and eat something substantial. Energy drinks are probably your go to, but please reconsider. Even swapping from energy drinks to coffee! Not ideal but it’s a start. If you’re always tired and never seem to be able to focus you need to find the root cause. Are you not sleeping well? That could be caused by energy drinks even if you don’t drink them straight before bed. Are you eating right? You could be deficient in essential nutrient that are making you feel constantly fatigued. You need to give your body what it needs and wants, and I guarantee you that’s NOT a can of Monster or Red Bull or any of those energy drinks out there.

Reference
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