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Relentless Nutrition Facts (In-Depth)

Since the drink’s launch in 2006, Relentless has skyrocketed to the stratosphere. It’s not hard to see why: the brand promises a good energy boost in 7 fruity flavours.

But what exactly is behind the Relentless recipe? What amounts of the essential ingredients for energy drinks are present in Relentless?

In short: Relentless contains many of the usual ingredients present in most energy drinks; 160mg of caffeine and 25g of sugar are the two main nutritional contents in Relentless that you might want to look out for.

In this article, I have discussed the nitty-gritty details of the products within Relentless and the amounts that are considered safe.

Read on to get to the good stuff!

Why are Nutrition Facts Important?

It would be best if you keep note of the amounts of various ingredients present in energy drinks. Too much of these can cause you to suffer from some nasty side effects.

Caffeine and sugar are two main ingredients that can cause you a myriad of problems if consumed excessively. With the high amounts of these present in Relentless, exceeding the daily limit can be very easy.

Many ignore the warnings provided on the back of energy drink cans or do not read them.

When you’re consuming something that can land you in the Emergency Room, it is necessary to be educated on avoiding that.

Relentless Energy Drink Ingredients

Before we get to the quantities of these, below is an easy-to-navigate table outlining all the ingredients present in Relentless.

Ingredient TypeIngredient
EnergisersCaffeine, Guarana Seed Extract
WaterCarbonated Water
PreservativesPotassium Sorbate, Sodium Benzoate
AcidCitric Acid
Acidity RegulatorSodium Citrate
VitaminsTaurine, Niacinamide,
Pantothenic Acid, Pyridoxine, Cobalamin
SweetenersSucralose, Sucrose
Flavour EnhancerErythritol
ColourCaramel E150d
Ingredients in Relentless Energy

Nutritional Facts of Relentless

Now that you know about the various products present, the table below provides the amounts of each of these in a regular 500ml (16 fl. oz) Relentless can.

Relentless Ingredients
Nutrition Information given on a Relentless can
IngredientQuantity (Per 500ml)Daily Value (%DV)
(108 kCal)
(Excluding Sugar)
Pantothenic Acid8.5mg142%
Vitamin B61.5mg107%
Vitamin B122.0μg86%
Nutritional values of Relentless Energy drink

Vitamins in Relentless

Relentless comes with high doses of several B-Vitamins; these can be both beneficial and harmful if taken in large amounts.

Vitamin B3 (Niacinamide)

Niacin or Vitamin B3 is one of the four B Vitamins present in Relentless. It has a variety of essential functions within the body; these include:

  • Improving blood fat levels
  • Reducing blood pressure
  • Improves skin health

However, it is mainly included in energy drinks due to its ability to burn body fats into energy, providing the user with an energy boost.

Vitamin B5 (Pantothenic Acid)

The principal functions of Pantothenic Acid are:

  • Maintaining a healthy digestive tract
  • Manufacturing red blood cells
  • Production of sex and stress-related hormones

Like most other B Vitamins, Pantothenic Acid also helps turn carbohydrates into glucose, giving the person an energy boost.

Vitamin B6 (Pyridoxine)

Pyridoxine also has its own set of functions. I have listed a few of these below:

  • Producing antibodies
  • Maintaining normal nerve function
  • Breaking down proteins

The last listed function is the primary reason this particular vitamin is included in Relentless; breaking down proteins into carbohydrates helps the drink achieve its purpose of burning fats.

Vitamin B12 (Cobalamin)

Vitamin B12 also goes by the name Cobalamin. Here are some of its essential functions:

  • Regulating DNA
  • Maintaining Normal Brain Function
  • Synthesis of Fatty Acids

Vitamin B12 also has its role in producing energy by helping the body absorb folic acid.

How Much Sugar Does Relentless Have?

Relentless contains a considerable amount of added sugar, a hefty 25 grams in a 500ml (16 fl. oz) can.

The National Health Service (NHS) recommends adults only have 30g of sugar per day, any more than that can cause you to face adverse health effects.

The amount of sugar in Relentless quantifies up to over 80% of your daily sugar intake limit. You will have to keep strict track of your other sources of sugar throughout the day and avoid going over the limit.

What Happens When You Have Too Much Sugar?

Keep your sugar intake at a minimum to avoid adverse health effects.

Excess sugar can be fatal depending upon your health condition and the total amount of sugar you’ve had.

Starting from the most well-known downside of sugar, it can cause cavities in your teeth. While you might roll your eyes at this upon hearing it as an adult, it is more accurate than you would like to think, especially if you don’t brush twice a day.

Studies have shown that over-indulging in sugar can cause Rheumatoid Arthritis; this disease makes your immune system attack healthy cells.

Sugar can also impact your heart, more so if you are already a heart patient. The surplus sugar causes the walls of arteries all over your body to be inflamed; this stresses your heart and might lead to a heart attack.

To counter these effects, some energy drink brands have started using artificial sweeteners to make their products sugar-free.

Calories in Relentless

Relentless contains 108 calories in a 500ml (16 fl. oz) can.

This amount is easy to ignore when looking at the 2,500 and 2,000 calorie limit for men and women respectively, but it can still hinder you if you’re looking to get back in shape.

However, if you are not aiming to lose weight, this amount might not affect you at all.

If you have a healthy and balanced diet and carry out light exercises daily, the calorie amount consumed through Relentless will be burned off fairly quickly.

Caffeine Content of Relentless Energy Drink

Caffeine is the primary energy source in Relentless, and the quantity determines how harmful or beneficial it can be for you.

Every 500ml (16 fl. oz) of Relentless contains 160mg of caffeine.

The Food and Drug Administration (FDA) advises healthy adults only have up to 400mg of caffeine per day; this amounts to almost two cans of Relentless.

It is essential to note your other caffeine sources, such as coffee and chocolate.

Ensure that you stick to one can a day to be safe.

Side Effects of Too Much Caffeine

If you drink Relentless in excess or exceed the daily 400mg limit, here are some side effects you can expect to face.

  • Restlessness & Shakiness
  • Insomnia
  • Headaches
  • Dizzyness
  • Abnormal heart rate
  • Dehydration

Long-term misuse of caffeine can cause dependency, and this can cause you to become reliant on caffeine to function on a day-to-day basis.

Watch the video below to find out more about the effects large doses of caffeine can have on you.

Artificial Sweeteners in Relentless

Splenda packets
Splenda is the most common artificial sweetener used in most food and beverages.

Although Relentless contains a significant amount of sugar, they also add Sucralose, a popular artificial sweetener, in their drinks.

While many other energy drink brands that depend upon artificial sweeteners are sugar-free, Relentless uses both sugar and sucralose to get its unique flavour.

Despite controversies, Sucralose has been tested and proven to be safe for consumption.

While being 600 times sweeter, Sucralose is also healthier than regular sugar.

Taurine in Relentless Energy Drink

Taurine is widely used in energy drinks due to its positive effect on mental and athletic performance.

Besides the function mentioned above, Taurine also has several vital tasks within the body.

One study that implemented regular doses of Taurine on people with congestive heart failure showed improvement in their exercise ability after two weeks.

Guarana Seed Extract in Relentless

Caffeine in energy drinks primarily originates from Guarana Seed Extract. Guarana is a plant native to the Amazon, and its seeds contain approximately four times the caffeine found in coffee beans.

Other natural chemicals present in Guarana are proven to boost the already high stimulant effects of caffeine.

Since caffeine in Relentless is extracted from Guarana, the side effects of both these ingredients are more or less the same.

Preservatives in Relentless

Relentless utilizes Sodium Benzoate and Potassium Sorbate to preserve its drinks for a more extended amount of time

Sodium Benzoate has a knack for being more effective in acidic foods, and it stops the growth of harmful bacteria and moulds in food.

Potassium Sorbate also has a similar function; it prevents mould, yeast, and fungi growth within Relentless, improving its shelf life.


If you’re looking for a suitable energy drink to implement into your diet and are not much affected by calories and sugar, Relentless may be the right option.

Its high amount of caffeine and B Vitamins will ensure that you get your desired heightened energy.

Make sure you keep your intake of Relentless to one can a day. Large amounts of caffeine, sugar, and vitamins can all be harmful to your health.

You don’t need me to tell you how bad a combined overdose of these can get. But if you have some underlying conditions and still opt to drink Relentless, better to talk with your doctor first before drinking a can of Relentless.

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