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Energy drinks

+   What’s in an Energy Drink?

An energy drink is a drink that contains some sort of physical or mental stimulant. Usually the stimulant is caffeine in some form but there are a number of other ingredients that energy drink companies can add:

  • Caffeine
    • A stimulant found in nature. On average energy drinks contain around 80mg of caffeine. As a comparison most fizzy drinks contain 18 to 48mg.
  • Guarana
    • This is a plant that contains high amounts of caffeine. In fact a guarana seed contains twice as much caffeine as a coffee bean. Energy drink producers often use guarana as the source of caffeine in their drinks
  • Sugar
    • Most energy drinks contain high amounts of sugar. They often even contain a larger percentage of sugar than fizzy drinks
  • B vitamins
    • Your body uses B vitamins to help convert sugar to energy
  • Taurine
    • This is a chemical naturally produced by your body and it helps to regulate your heart beat and muscle contractions
  • Inositol
    • This is more rarely included
    • It is the chemical that helps to relay messages inside your cells
  • Ephedrine
    • Also less commonly used
    • It is a stimulant that works to stimulate your central nervous system
    • There are some concerns about ephedrine’s effect on your heart
  • Creatine
    • Creatine’s main role in the body is to help supply energy to cells, mostly your muscles
  • Ginseng
    • Ginseng is a root
    • In Asian medicine it has long been believed to boost energy

+   How do they Work?

Caffeine and sugar are the two heavy lifters in energy drinks and the effects of energy drinks are based mainly on those two ingredients.


Sugar is a fundamental fuel for the body and brain. Usually energy drinks contain some form of fructose or glucose or a mix of both.

  • Glucose is what your body primarily uses for energy. It is broken down in the process of respiration. This where oxygen is used by your body to break the chemical bonds of glucose which releases energy as well as CO₂ and water. This energy is then stored in another chemical form ATP which also releases energy when broken down.
  • Fructose is a different form of sugar. It is processed by the liver to create glucose and then the glucose is used to create energy. It can replenish energy stores quicker than glucose so gives you faster boost. However, the liver can only process so much fructose at a time and the rest is turned into fat.


Caffeine works to give you energy by effecting adenosine and dopamine uptake and by making your body produce adrenaline:

  • Adenosine is the chemical in the brain that makes you feel sleepy and tired. Caffeine prevents the normal effects of this chemical by binding to nerve receptors in its place. This stops you from feeling sleeping.
  • Caffeine also leads your body to produce adrenaline. This is the chemical released when your body thinks there is an emergency. It will increase your heart beat, open your airways and release extra energy into your blood making you feel more alert and focused
  • Caffeine prevents the re-absorption of dopamine. When dopamine floats around it activates the pleasure centers of the brain so when caffeine stops it from being reabsorbed the levels rise and you feel happy.

+   Are Energy Drinks bad for you?

To a student energy drinks may appear to be the best thing since toast however, is it really healthy to be relying on caffeine and sugar for your energy? What side effects can consuming too much of these drinks have in both the long and short term?

Red Bull the king of energy drinks has been banned in France, Norway and Denmark. But this an extreme reaction and in the UK they investigated energy drinks and issued a warning for the use by children (under 14) and pregnant women. Though energy drinks consumed in large quantities can have serious side effects, one or two cans won’t do you much harm. Different people will react to different amounts of caffeine in different ways and some will notice the below side effects after just one can. In general though, it takes 300 – 400mg of caffeine or 3 -4 cans of the average energy drink to see these effects.

  • Agitation and anxiety
  • Insomnia
  • Jitteryness or shaking
  • Abnormal heart beat
  • Irritability
  • Increased urination and dehydration

Due to the potential side effects you should not drink energy drinks if you have heart problems or before exercising. This could lead to serious heart conditions or severe dehydration.

Energy drinks also contain a lot of sugar. Large quantities of sugar lead to an energy spike and then a crash. Too much sugar can also contribute to conditions like obesity, heart disease and diabetes. If you are diabetic you should be aware of the amount of sugar present in energy drinks.

+   Alcohol and Energy Drinks

Energy drinks and alcohol have opposite effects on your body. While energy drinks stimulate your system, alcohol depresses it. This can have dangerous consequences. Though Jagerbombs and vodka Red Bulls are popular ways to start the night, mixing alcohol and energy drinks should be done carefully and in moderation:

  • The effects of energy drinks mask the effects of alcohol
    • This means you won’t realize how drunk you are increasing the chance of alcohol related injuries and alcohol poisoning
  • Severe dehydration
    • Both alcohol and energy drinks can lead to dehydration. Combined they can leave you dangerously dehydrated
    • It will also lead to a killer hangover
  • Heart Failure
    • There are a number of smart people out there who have shown that drinking alcohol alongside energy drinks can increase the risks of heart failure

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