Energy drinks have become a staple of university life for many students. Between balancing deadlines, late nights and early morning lectures, work and socialising, students often turn to energy drinks for that quick caffeinated boost. And while it seems like the best solution at the time, turning this caffeine consumption into a frequent habit can actually be more harmful than you realise. Excessive caffeine intake can instead have detrimental effects on the body, including heart health, mental health, and sleep. Knowing the dangers of energy drinks and excessive caffeine is key to keeping yourself safe and healthy.

Caffeine is a natural psychoactive stimulant, meaning it acts primarily upon the Central Nervous System. It is arguably the most consumed psychoactive substance worldwide, and when consumed in moderation, it can provide numerous benefits. Caffeine acts by blocking adenosine receptors in the brain, preventing signals of fatigue from being registered by the brain. This reduces feelings of tiredness, increasing focus and alertness: the effects desired by many university students. It also enhances dopamine signalling in the brain, leading to increased attention and improved mood.

However, all of these effects occur on a temporary basis, often leading to a “crash” hours after the caffeine begins to wear off. While the shortlived effects may be advantageous in the meantime, the long-term consequences of excessive caffeine consumption can pose more harmful effects across the entire body.

When caffeine blocks the adenosine receptors, it also triggers the release of adrenaline, more commonly known as the “fi ght-or-fl ight” hormone. While this may enhance physical energy and alertness in the short-term, it also can result in elevated heart rate and blood pressure. Over time, when caffeine is consumed excessively, this spike becomes more difficult for the body to regulate, with the potential to lead to irregular heart rhythms, increasing the risk of cardiovascular events.

Sleep patterns are easily disrupted by caffeine. With one of its most desired benefits being
keeping you awake, this also means that falling asleep when you want to may become more difficult, and you may be prone to more frequent awakenings throughout the night. Caffeine doesn’t just affect your quantity of sleep, but also its quality. Excessive caffeine consumption has been linked to a reduction in REM sleep and slow wave sleep, both of which are essential for physical and mental recovery. This can result in feelings of tiredness even after sleeping for sufficient time.

Excessive caffeine can often lead to discomfort with digestion due to its interactions with the gastrointestinal system. It can trigger an increased release of Gastrin, a hormone responsible for the secretion of stomach acid and digestive enzyme activity. Caffeine also stimulates the gut muscles and speeds up Peristalsis; the muscle contractions which move food through the intestines. This can result in a number of uncomfortable effects, from heartburn and acid reflux to stomach pain and diarrhoea. While regular coffee consumption is often associated with a lower risk of depression and cognitive decline, excessive caffeine intake from coffee and many other substances can have harmful effects on mental health. The increased release of neurotransmitters such as dopamine, serotonin and norepinephrine helps with mood regulation in the short time.

However, the very same neurotransmitters can prove harmful if this release occurs too often. When their release is greatly increased due to excessive caffeine intake, it can mimic the symptoms of anxiety such as nervousness, restlessness, and increased heart rate.
Caffeine can also amplify symptoms in those with pre-existing mental health conditions, where excessive amounts may exacerbate psychiatric and psychotic symptoms and is often linked to an increased risk of panic attacks.

Excessive caffeine consumption can also result in dependence, where a larger dose is required to produce the same desired effects. Due to the stimulatory nature of caffeine, it meets the necessary pharmacological criterion to be classified as a psychoactive drug. When chronic caffeine consumption is stopped abruptly, it can trigger withdrawal-like symptoms such as headaches, fatigue, and irritability. Many cases also present flu-like symptoms such as nausea and muscle pain. A gradual decrease in caffeine consumption as opposed to an abrupt cut-off can help minimise the symptoms of withdrawal.

Energy drinks are usually advertised with their enhancing effects, which, alongside their variety of fun flavours and convenient packaging, make them so popular. However, they often have a high caffeine concentration. A typical 250ml can of Redbull contains approximately 80mg of caffeine, while Original Monster Energy contains approximately 160mg of caffeine per 500ml, with such concentrations fluctuating depending on certain flavours. Caffeine can be found in other foods and drinks, most notably teas, coffees, sodas, and chocolates. Many of them contain a much smaller concentration of caffeine in comparison to energy drinks. However, this, paired with energy drink consumption, makes it easy for caffeine to build up in your system without even realising.

The NHS recommends limiting caffeine intake to 400mg per day. Caffeine sensitivity is person dependent, however, meaning some may experience the negative effects of caffeine while having consumed a much smaller dose than the recommended limit. This sensitivity can be dependent upon genetics and individual caffeine tolerance. Knowing the symptoms of excessive caffeine consumption and its risks, alongside monitoring your caffeine consumption, is key to staying healthy.