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Relentless Energy Drink Review (All You Need To Know)

Energy drinks are formulated to enhance energy and cognitive performance. They’re a blend of sugar, vitamins, caffeine, amino acid derivatives, and herbal essences.

Relentless Energy Drink was made by The Coca-Cola Company in February 2006 and is a popular energy beverage.

If you’re keen to learn more about this drink then please give this article a read till the end.

Nutrition Facts of Relentless Energy Drink

NutritionPer 500ml (%*)
Energy461kJ (108kcal) (5%)
Carbohydrate31g (12%)
Of which sugars24g (27%)
Salt0.70g (12%)
VitaminsPer 500ml (%**)
Niacin (Vitamin B3)16mg (100%)
Pantothenic Acid (Vitamin B5)8.5mg (142%)
Vitamin B61.5mg (107%)
Vitamin B122.0mg (80%)
Nutritional Facts

Ingredients in Relentless Energy Drink

Ingredients in Relentless Energy Drink are listed below:

  • Carbonated Water
  • Sucrose
  • Acid (Citric Acid)
  • Flavour Enhancer (Erythritol)
  • Taurine (0.4%)
  • Acidity Regulator (Sodium Citrate)
  • Preservatives (Potassium Sorbate, Sodium Benzoate)
  • Colour (Caramel E150d)
  • Caffeine (0.3%)
  • Flavourings
  • Sweetener (Sucralose)
  • Vitamins (B3, B5, B6, B12)
  • Guarana Seed Extract (0.005%)

Taurine in Relentless Energy Drink

Relentless claims to contain some amount of taurine in it. Basically, taurine is an amino acid that helps your heart and brain to perform some important functions and even helps control blood pressure and the nervous system.

Human bodies can produce their own taurine except for seriously ill individuals who may take supplements for this nutrient. Having an amount of taurine in your energy drink can:

  • Support Nerve Growth
  • Lower Blood Pressure
  • Help in calming Nervous System
  • Prevent Heart Failure
  • Enhance Energy
  • Enhance Athletic Performance


There are two preservatives, Potassium Sorbate and Sodium Benzoate, used in Relentless Energy Drink.

Preservatives are added to foods because they fight against moulds, fungus, and yeast. Additionally, they help in slowing down the changes in taste, texture, and colour.


Sucralose is an artificial sweetener and it’s used as an alternative to regular sugar. It’s around 400 to 700 times sweeter than our regular white sugar. It includes benefits such as caloric intake control and doesn’t promote tooth decay.

Undesirable effects can also occur:

  • Risk of Diabetes
  • Higher Risks of Crohn’s Disease and Irritable Bowel Syndrome
  • Links to Leaky Gut
  • Production of Toxic and Carcinogenic Compounds in High Temperatures
  • Weight Gain

Guarana Seed Extract

Guarana is a Brazilian plant, with large leaves and flowers. We obtain Guarana extract by crushing its seeds into powder.

Amazonian tribes have been using guarana for centuries. It’s a natural stimulant containing caffeine, theobromine, and theophylline.

This ingredient is known for having high contents of caffeine and provides certain benefits like:

  • Aid in fatigue Reduction
  • Weight loss
  • Treatment of constipation and diarrhoea
  • Promotes Cardiac health
  • Healthier skin
  • Includes antibacterial properties

Similarly, it also has side effects like:

  • Heart Palpitations
  • Insomnia
  • Headaches
  • Seizures
  • Anxiety
  • Nervousness
  • Upset Stomach
  • Shakiness

Vitamins in Relentless Energy

Relentless has vitamins to boost your energy levels.

Vitamin B3, Vitamin B5, Vitamin B6, and Vitamin B12 are present in Relentless.

Generally, B vitamins provide benefits to your body by promoting:

  • Red Blood Cells development
  • Energy Levels
  • Good Eyesight
  • Healthy Brain Function
  • Good Digestion and Appetite
  • Healthy Cells and Nerve Function
  • Cardiovascular Health
  • Muscle Tone

B vitamins are beneficial for your body, however, their overdose may harm your health. Following adverse reactions may occur:

  • Skin Problems
  • Bad Eyesight
  • Abdominal Cramps
  • Nausea
  • Vomiting
  • Increased Urination
  • Diarrhoea

What Are Flavour Enhancers?

The idea of taste enhancement was first introduced in Asia. Flavour enhancers when added to food, increase its natural flavour.

What does a Flavour Enhancer do?

Flavour Enhancer improves the flavour of foods if used in little quantity.

It’s utilized in marinades, sauces, soups, potato chips, noodles, savoury rice, cured meats, vegetables, cheese, snack foods, and much more. Furthermore, it also works as a dry seasoning, which is sprinkled on foods.

How Much Caffeine is in Relentless Energy Drink?

500ml serving of Relentless contains 160mg of caffeine.

Caffeine helps your body in various ways:

  • Helps in weight loss
  • Enhance performance
  • Improves rain function
  • Alzheimer’s and parkinson’s disease. …
  • Improves memory
  • Liver and colon
  • Eyelid spasm

As claimed by the EFSA, up to 400mg of caffeine is recommended for a physically active and healthy adult.

How Much Sugar is in Relentless Energy Drink?

500ml Relentless contains 24g of sugar.

The recommendation by NHS for sugar consumption for an adult is not more than 30g in 24hrs.

Excessive consumption of sugar may show the following side effects:

  • Weight Gain
  • Increase the Risk of Heart Disease
  • Acne issues
  • Increases Risk of Type 2 Diabetes
  • Increase Risk of Cancer
  • Risk of Depression
  • Accelerate the Skin Ageing Process
  • Can Increase Cellular Ageing.
The back of the can.

Do Energy Drinks Provide Energy in the Form of Carbohydrates?

Sugars are a supply of carbohydrates, which deliver energy to your cells but can be modified into fat if the energy is not played out.

Moreover, in an energy drink, sugar doesn’t give an added benefit. Sugar-free energy drinks do not have extra glucose but have other elements of carbohydrates.

What are Carbohydrates?

Carbohydrates (also known as carbs) are a kind of macronutrient present in particular foods and beverages. Starches and sugars are mostly carbohydrates.

Additional macronutrients include fat and protein. Your body requires these macronutrients to stay fit and healthy.

Is Relentless Energy Drink Bad For You?

I think Relentless energy drink’s consumption within limits isn’t bad for you as it contains many healthy ingredients.

However, there are certain ingredients that can be harmful to you.

In my opinion, 160mg of Caffeine in a 500ml serving is not very ideal. You should be mindful of your caffeine tolerance and if you are strictly taking only one drink a day then it can be considered harmless.

Mindfulness is the key to health and if you’re not being mindful enough with your energy drink intake then you can face complications like:

  • Anxiety
  • Insomnia
  • Weight Gain
  • Digestive Issues
  • High Blood Pressure

What Happens When You Drink Relentless Energy Drink?

Relentless gives you the much-needed wake with a touch of an impressive energy push.

Relentless can help you with your workout routine as it keeps you focused and mentally alert. Moreover, It also gives you an energy push to keep you awake and helps you get rid of tiredness.

How Long Does It Take For Relentless To Kick In?

After drinking Relentless, within half an hour you’ll be perked up and energized. The caffeine level in Relentless will take around 10-15 minutes to reach your blood and further 15-20 minutes will be required to fully absorb the stimulant, thereby elevating your energy level.

How Long Does A Relentless Energy Drink Last?

The effects of Relentless drink will lessen with time. Generally, it takes around 12 hours to fully eliminate caffeine from your system. But, it mostly depends on your lifestyle and physical health.

Can You Drink Relentless Energy Drink Every Day?

If you’re someone with no medical condition then you can drink Relentless daily. There is no harm in enjoying a can once a day if you are physically fit and have no major ailment.

However, there’s a caution on the can, saying if you’re pregnant, breastfeeding, or have any sensitivity for caffeine then you should be more careful while consuming the drink.

Read carefully

How Much Relentless Energy Can You Drink In A Day?

The first and foremost thing that matters is your health. As we have already discussed, Relentless energy drink contains a great amount of sugar and caffeine, so be cautious of its side effects.

To be on the safer side, start by consuming 250 ml a day and observe how your body reacts to it. If everything goes well then you can increase its intake. However, in my opinion, one can a day is safe for a healthy adult.

What Does Relentless Energy Drink Taste Like?

Relentless has a very refreshing taste. Its sweet and fruity flavour lingers on and you’ll not feel any bitter taste afterwards.


Relentless has 7 different flavours each one having its unique taste. The flavours are:

  • Origin
  • Passion Punch
  • Zero
  • Apple Kiwi
  • Mango
  • Lemon Ice
  • Cherry

Where Can You Buy Relentless Energy Drink and How Much?

Relentless energy drink is easily available from your nearby shops and if you prefer online shopping then order from Amazon, eBay, or any other online website.

As far as its price is concerned, you can get a single can of 500 ml Relentless at around £1, however, it would cost you less if you purchase in bulk.

Alternatives to Relentless Energy

Bottom Line

A 500ml serving of relentless works great as a booster and contains a perfect blend of ingredients and B vitamins.

Remember, in order to prevent side effects, you should avoid excessive drinking. This drink contains a significant amount of caffeine so you should be careful.

Caffeine can be found in a bunch of other foods we eat on daily basis as well. Relentless affects each person differently, depending upon physical health.

So if you enjoyed reading all I had to say about this drink then go ahead, grab a can and enjoy a can of Relentless.

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