Can You Drink Relentless Every Day? (Healthy Or Not)

Relentless Energy Drink can

Relentless energy drinks are manufactured in Ireland and are famous throughout the UK. With its wide range of fruity flavours and a brand image that emphasises artistry and a passion for life, it’s no wonder that Relentless has struck a chord with the younger crowd.

You’re probably reading this post because you’re a fan of Relentless.

But as much as you might love it, the big question lingers:

Is it okay to drink Relentless on a daily basis?

Although this is certainly a matter of personal preference, let me help you make a better-informed decision with some helpful information and insights.

Where Can I Buy Relentless Energy Drink And How Much Does It Cost?

If you live in the UK, you should be able to get a can of Relentless energy drink quite easily from your local convenience stores or supermarkets.

But even if you live elsewhere, there’s no need to fret since you can always go online to hunt for the supply of Relentless drinks that you need. The only snag about that would be that you may have to bear extra costs for shipping.

Prices will definitely vary depending on where you buy it from, but in general, you can expect a 500ml can of Relentless to cost around £1 not including shipping costs.

Relentless Energy Drink Flavours

Relentless energy drink offers you a choice of seven flavours, with many of them being fruity:

  • Origin (the original flavour)
  • Zero (sugar-free version)
  • Mango
  • Lemon Ice
  • Cherry
  • Passion Punch
  • Apple Kiwi

Relentless Energy Drink Ingredients

A close-up view of the list of Relentless energy drink ingredients as seen on the can.
A Relentless energy drink contains quite a lot of sugar and caffeine.

What actually goes into your body each time you chug a can of Relentless?

It’s important that you know this because this will ultimately help you decide whether having Relentless energy drinks on a daily basis is a good thing for you or not.

In every 500ml Relentless Origin energy drink, you will find:

  • 108 calories
  • 160mg caffeine
  • 31g carbohydrates
  • 24g sugar
  • 0.70g salt
  • 16mg niacin (vitamin B3)
  • 8.5mg pantothenic acid (vitamin B5)
  • 2.0µg vitamin B12
  • 1.5mg vitamin B6

It also contains trace amounts of:

  • Carbonated water
  • Sucrose
  • Citric acid
  • Erythritol (flavour enhancer)
  • Taurine (0.4%)
  • Sodium citrate (acidity regulator)
  • Potassium sorbate
  • Sodium benzoate
  • Caramel E150d (colour)
  • Sucralose
  • Guarana seed extract

Let’s direct our attention to three main ingredients here: Caffeine, sugar, and vitamins.


A can of Relentless has 160mg of caffeine in it.

Assuming you are consuming just one can at a time, this would be a reasonable quantity for you to drink every day.

The reason that I say so is because the European Food Safety Authority (EFSA) says that you can enjoy up to a maximum of 400mg of caffeine per day. However, it also recommends that you only take 200mg of caffeine per serving.

Personally, if you’d asked me, I’d say I prefer to opt to for energy drinks that have between 50mg to 100mg of caffeine per serving though.

However, if we go by the EFSA guidelines, you would be able to actually drink up to two cans of Relentless a day. But I would advise against drinking that much since you need to make allowances for other food in your diet that may also contain caffeine.

Besides that, if you have any existing health problems, it would be wise to consult your doctor first before adding Relentless to your diet.


Relentless energy drinks contain 24g of sugar per can.

However, Relentless Zero would be an exception here as it is the sugar-free version of the beverage.

According to the National Health Service (NHS), we should not have more than 30g of free sugars in a day.

“Free sugar” here refers to the sugar added to the food and drinks we consume, and also includes sugar found in things like honey, syrups as well as unsweetened fruit and vegetable juices.

Although you’ve not yet exceeded your daily quota by drinking one can of Relentless, it doesn’t leave you with that much room for the sugars you will be consuming from other items in your diet.

As such, I’d say that taking anything more than one can of Relentless a day might be pushing the envelope from a sugar standpoint.

It’s important to keep a close watch on the quantity of sugar you take every day as you’d want to avoid health problems such as these:

  • Weight gain
  • Heart disease
  • Acne
  • Type 2 diabetes
  • Cancer
  • Depression
  • Skin ageing
  • Fatigue
  • Fatty liver
  • Kidney disease
  • Gout
  • Dental cavities


A top view of a table with a glass of orange juice, oranges and a bowl full of orange pulp.
A regular intake of vitamins is important for your overall wellbeing.

Relentless have been pretty transparent about how much of each type of the B vitamins that have been included in each 500ml can.

Here’s a quick comparison of the B vitamins that you’ll find in every can of Relentless vs. what your daily consumption should be:

VitaminQuantity In Relentless Energy Drink (500 ml)Daily Recommended Intake
Niacin (B3)16mg16 mg (men)
14mg (women)
Pantothenic Acid (B5)

Cobalamin (B12)2.0µg2.4µg
Summary of B vitamins in a can of Relentless energy drink

You may have noticed that some amounts of B vitamins that you’d find in a can of Relentless is more than what’s required for your daily dietary intake, but this shouldn’t be a cause for concern for you.

Usually, you can’t overdose on vitamin B whenever you are getting them from your food or drinks because these vitamins are water-soluble and anything in excess will not be stored in your body.

It will just get excreted in your urine instead.

How Does An Energy Drink Like Relentless Benefit Me? 

Energy drinks like Relentless provide you with a quick energy boost so you become more alert, have a higher productivity rate and/or perform better in physical activities such as sports.

Some sources have even claimed that caffeine, which is one of the major ingredients in energy drinks, can even help you with your long-term memory.

With the variety of flavours that Relentless has to offer, you can have the liberty of enjoying something different to suit your changing mood and tastebuds each time. This gives you a wider element of choice that isn’t so easily available with coffee or tea. 

Besides that, it’s readily available everywhere, making it convenient for you to enjoy the perks of caffeine at a more affordable price than your average cup of gourmet coffee. 

Nutrients that are found in a Relentless energy drink such as the B vitamins that we have talked about may also contribute towards your overall health in some ways. 

However, there are also health risks that you may face when consuming energy drinks like Relentless more often than you should. 

For example, you may become overly dependent on energy drinks and develop an addiction to them. 

In addition, the high levels of caffeine and sugar found in Relentless energy drinks may cause you other health problems including: 

  • Migraine
  • Diabetes
  • Obesity
  • High blood pressure
  • Muscle tremors 
  • Mental health issues
  • Dehydration
  • Insomnia 

How long does it take Relentless energy drink to work?

The short answer is that you will feel the effects of drinking Relentless for only about an hour or two before the effects start to wear off.

Once you have had a can of Relentless to drink, its caffeine content would have entered your bloodstream within 10 minutes. 

Over the next 45 minutes, your level of concentration and alertness should improve noticeably as the level of caffeine in your bloodstream reaches its peak. This is when you will feel the most energized.

About one hour after you have had a Relentless drink, you may start to feel tired as the effects of the sugar and caffeine you consumed start to wear off.

However, it will take another five to six hours before your body is able to eliminate 50% of the caffeine you ingested.

On average, your body would only succeed in clearing all the caffeine from your bloodstream after 12 hours or more from the time you first had a sip of a Relentless energy drink. 

But how long this actually takes for you might be different from what someone else experiences as it is dependent on your personal health and lifestyle.

For example, it was found that caffeine elimination from the body was quicker in smokers and those with heavy caffeine consumption habits.

Can you drink Relentless every day?

Yes, you can drink Relentless every day if you want to.

However, be mindful of how your body reacts to the caffeine and sugar in Relentless and use that to determine whether you should continue taking it every day.

If you are new to drinking energy drinks, it might be wiser to begin with taking only half a can of Relentless at a time and to monitor your body’s reaction to the caffeine. If you experience any negative side effects, then you might need to stop taking the drink and even see a doctor if the symptoms persist.

Since drinks like Relentless contain high amounts of caffeine, I would recommend that you drink it in the morning so that your body has more time to absorb it and you can then benefit from the effects of caffeine throughout the day. 

It’s also worth opting for Relentless Zero (the sugar-free version) to avoid the 24g of sugar that you would end up drinking if you had any of the other flavours. But that’s just my opinion.

Check out this video for some quick yet useful pointers to keep in mind if you decide to have Relentless energy drinks every day. 

Watch for some useful tips on what you should do when you take energy drinks every day.

How Many Relentless Energy Drinks Can I Have In One Day?

A close-up view of the Relentless logo on a Relentless Origin can.
Stick to just one can of Relentless a day.

My advice would be to stick to having just one can of Relentless a day.

Each can contains 160mg of caffeine and 24g of sugar a can. These quantities don’t exceed the recommended daily limit for both caffeine and sugar. 

However, you’ve got to remember to take into account the other things you’ll be eating and drinking within the same day. 

Guidelines given by the NHS tell us that we shouldn’t take more than 30g of free sugars in a day and 24g from just one beverage doesn’t leave you with much room for consuming other sugary foods. 

Another thing to keep in mind is what time of the day you choose to drink your Relentless energy drink. Doing so too late in the day might cause you to have trouble sleeping. 

If you do decide to go beyond one can of Relentless in a day, it would be better to go for Relentless Zero since it’s sugar-free and you won’t bust your daily sugar limit of 30g while doing so. 

Even so, you need to be wary of how the higher intake of caffeine affects your body. If it has a negative effect on your body, you will need to cut down your consumption of Relentless drinks.

Or if things get really bad, you might need to stop taking them altogether.

Alternatives to Relentless

If you would like to consider other energy drinks besides Relentless, here’s a list of ready-to-drink beverages you can try: 

Another option you might want to look into is powdered energy drinks. Besides being more compact in nature and easy to take along with you wherever you go, they can be mixed with any of your favourite beverages (although alcohol would not be a good idea, of course). 

Here are some brands you can look out for: 


A sachet of REIZE energy powder and a glass of REIZE energy drink.
Give REIZE a try.

REIZE is a great alternative to Relentless energy drink.

It has a lot less caffeine than Relentless (only 50mg per sachet, which means it has less than half the amount found in Relentless, which has 160mg in it) and is sugar-free.

Besides that, REIZE also has a great combination of ingredients in it and this includes ginseng, taurine, and B vitamins which will certainly help you in maintaining optimal energy levels all day long.

Being in a powder form, REIZE gives you the flexibility of enjoying your energy drink together with your favourite beverage.

You can also control how strong you’d like your energy drink to be by adjusting the volume of liquid that’s mixed with REIZE. (Although you’re typically advised to add one sachet to 250ml of water.)

Last but not least, REIZE costs only around $1 per sachet, and this price is inclusive of shipping too.

So if you’re thinking of what to get as your next energy drink, consider choosing REIZE.

I guarantee you won’t be disappointed!

Last Updated on

Marty Spargo

I started my own energy drink brand in 2014 and am passionate about educating people about energy drinks so that they can properly understand the ingredients, benefits and risks without being influenced by the marketing messages put out by some brands. You can read my full bio here.

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