Ask LH: Should I Be Drinking Coke Zero Or Coffee?

Ask LH: Should I Be Drinking Coke Zero Or Coffee?

Dear Lifehacker, I drink one can of Coke Zero each day and close to two litres of water. I drink the Coke for the caffeine as I do not like coffee. Could you supply some nutritional info on the differences between coffee and Coke Zero? The benefit for me is the caffeine. Thanks, Mister Night Shift

Coffee picture from Shutterstock

Dear MNS,

First up, great job on the H2O intake! Favouring water over soft drink (even if it’s the diet variety) is definitely recommended.

Coke Zero contains zero kilojoules or sugar. It derives its sugary taste from the artificial sweeteners aspartame and acesulfame K. The former was recently linked to metabolic disease and digestive problems, although no clear consensus has been reached. It is, however, something to keep in mind.

In terms of caffeine content, Coke Zero contains 9.6mg per 100ml. This is substantially less than coffee which packs in up to 40mg per 100ml. However, there is a lot more variation in coffee depending on the type of coffee bean, the amount of milk used and how it is prepared. By contrast, the caffeine in Coke is artificially added to a precise dosage.

So to answer your question, coffee gives you a lot more bang-for-buck than Coke Zero. If you don’t like the taste of coffee, you might want to give a diet energy drink a try instead: you can find a rundown of products and how they taste here. (Our picks: V Energy Sugar Free or 28 Black Sugarfree.)

Interestingly, Diet Coke actually has more caffeine than Coke Zero at 12.8mg/100ml. This is something to keep in mind if you want a slightly bigger hit of caffeine per can. You may also want to consider black tea: a strong brew can contain up to 20mg of caffeine per 100ml, alongside antioxidants and other health benefits that Coke Zero lacks.

We’re keen to hear what other readers think. What’s your caffeine beverage of choice? Or do you ingest it a different way? Share your recommendations (and warnings) in the comments section below.

Cheers Lifehacker

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  • Caffeine is fine, but sometimes the sugar itself is the real (temporary) energy provider.

    People give refined sugar shit as ‘unhealthy’ mostly because we almost all universally get excessive amounts of it already. But there’s nothing actually inherently ‘bad’ about sugar on its own. Glucose, fructose… they just have different properties with different effects you need to be aware of. The difference is always down to quantity and timing. (Also, be wary when researching Coke – US Coke is made from high-fructose corn syrup, whereas Australian Coke uses cane sugar, which has a much lower fructose content. Any advice you receive about coke from American sites is likely to be based around corn syrup coke.)

    If you’re careful and sensible with your intake for the rest of the day and using stimulants (like caffeine) to get past a sticking point in a night shift, switching to ‘real’ Coke could actually be the extra firepower you’ve been looking for.

    • I always wondered about this as well. For example I see people quick to say sugar in say is unhealthy, but sugar in an apple is “good sugar”. But I figured they both likely came from a plant through photosynthesis so it didn’t make sense to me.
      The only thing I would understand is the concentration of sugar in an apple is a lot less then but as you say then its just a ” everything in moderation” thing. Not a “apple sugar good, coke sugar bad because reasons”.

      • Year 10 chemistry probably has a lot to answer for.

        Like, for example, here’s the gross oversimplification I was taught:

        Sugars ain’t sugars, to misquote an oil ad. A big part of how ‘healthy’ something is is down to your body’s need for it, or use for it. Sugar that you burn is good. It’s the ONLY thing you ‘burn’, once the internal refinement process is done.

        It’s why the glycemic index (GI) – the measure of how quickly you break a compound down into the eventually-used glucose molecule – is important. Broadly speaking, a compound might be considered a ‘sugar’, but it’s laden down with all these other atoms that form easier or more difficult to process molecules. And the ‘good’ sugars and foods with low-GI are often the ones that are slower to break down and release those juicy fuel goods. High-GI (simple/refined sugars which are damn near sugar molecules in solid form) are ‘bad’ because they get accessed so quickly.

        You aren’t ALWAYS using the sugars for fuel, and if you put more into your system than you’re burning, they get stored as fat, which is only the beginning of PART of the problem. Like pouring kerosene onto a campfire and expecting that to be all the fuel it needs for the rest of the night. Bzzzt.

        And that’s without going into the difference between what can be broken down by simple saliva or digestive enzymes and which ones need to take a tour through your liver to crack open and get at, like fructose. (In general, things that have to go in your liver are usually, well… toxins. Poisons. Things which are harmful to keep in the system for too long owing to how they react with everything while they’re unprocessed. And the liver refuses to work any harder than it has to, so giving it a huge workload means there’s a backlog of poisons just… sitting there being poisonous. And if it has to work too hard, the liver can get sloppy and let things slide. Etc.)

        And I know there’s a hell of a lot more to it all than that, but it’s so fucking drowned out by all these people who don’t talk mechanics but talk JUDGEMENTS, saying that more or less of this or that is ‘bad’ or ‘good’. Like with salt. People give salt a lot of shit because the majority of the time it’s too high. But it’s vital, you need it, and it’s not ALWAYS too high. But if you see some well-meaning idiot’s diatribe on how bad salt is, and take it to heart, and you NEED it, then you’re actually doing more harm than that extra bit of salt would do to someone who has too much already.

        We can make some assumptions based on modern diets and statistics, but in general, unless you know exactly who you’re talking to, and their diet, physiology and behaviours, calling things ‘good’ or ‘bad’ foods, is always the potential to be making a pretty huge mistake.

      • The “good sugar” in an apple also comes with water, fibre, vitamins, and it takes your body time to chew and digest. In fact, some of it won’t be digested at all. Anyone who has tried to eat their way through a plate of celery sticks knows there’s an upper limit to how much fibre you can put in before you simply have to stop. That doesn’t happen when you’re snacking on gummy bears. So it’s less about the sugar itself, and what other nutrients you’re missing out on if you rely on refined sugars instead of natural ones.

    • Bananas were always the go-to energy packet for when I was swimming. Seemed pretty reliable, but when you’re a ravenous teen/early-20s walking garbage disposal, it’s hard to tell.

  • Aside from the fact that Diet contains more caffeine than Zero, it also tastes a hell of a lot better.

  • While the quantity of caffeine per millilitre is much less than for coffee, the serving size is also much larger. For coffee you would be drinking around 250ml; for Coke Zero, at least 375ml and likely 600ml, so the caffeine dosage is increased by a factor between 1.5 and 2.5.

    Aspartame is still GRAS but there’s no real doubt that it’s better to just drink water rather than diet cola. Personally I’m fine with drinking diet cola; if the link between aspartame and metabolic syndrome is small enough that they haven’t nailed it down by this point, it’s unlikely to be a large enough effect to be worth worrying about.

    As for coffee – it’s been the focus of many studies as well, but while occasional studies have shown beneficial or detrimental effects, again the effect seems to be too slight to be worth worrying about.

    • I’ve always wondered if it’s just some people are sensitive/incompatible with Aspartame. Similar to lactose I guess. I always feel really bad after having a drink or food with aspartame. I get the same weird feeling in my stomach intestines each time. (and yes there’s been times I got the feeling and then read ingredients and found aspartame to my surprise.)

  • Interesting article, I was always told that coke zero had the most caffeine, which is a shame it doesn’t because its my favourite, it doesn’t taste as sweetened or as attack-like on my tongue like normal coke or diet coke.
    I usually like coke more as I can drink it throughout the day as well to try to pep me up when I get tired as opposed to coffee which really can only be drank straight away (and typically in the morning).

    I would’ve liked through (and I kind’ve assumed that the OP was more leading too) the health wise benefit. Like is coffee more healthier due to x or y, is coke zero neither healthy or unhealthy as its basically water and sweetener? You did discuss the aspartime though which is appreciated.

    I guess I was just interested in knowing is Coke Zero actually healthyish? Like I don’t expect it to have positive vitamins and minerals, but it doesn’t seem to have negative ones besides the aspartime? I’m also interested if using stevia means you get a quite adequate drink? (like pepsi is doing)

    • A good question, see my reply above regarding Aspartame. In regards to Stevia, here is an excellent article by The New Yorker about the whole industry and Stevia in particular. It’s lengthy, but a great read:
      Softdrink/Soda companies are spending inordinate amounts of money to produce drinks based on Stevia as it is a naturally occurring chemical compound, not synthetic. This means nothing regarding the actual health benefits, but has huge ramifications for “perceived” health benefits by the greater (uninformed) public. It’s not surprising that they play up the marketing on these products as “life” and in green bottles.

  • I will add that most coffee in Australia is made with a lot of milk which adds a huge amount of calories. If you are trying to calorie count and still need your caffeine hit stick to the Diet Coke/Coke Zero.

  • How exactly does adding milk reduce the amount of caffiene in any particular beverage as this article infers? How does black tea, have more caffiene than white tea, given that white tea is just black tea with milk added? How does the milk in a latte reduce the amount of caffiene in the drink compared to what’s in an espresso given that a latte is an espresso with steamed milk added? The volume of each drink is different so comparing caffiene per unit volume is utterly pointless.

    • To answer your question, straight coffee drinkers tend to prefer a stronger brew, particularly if they’re having a long black. (‘Black tea’ was a reference to leaf type, not the absence of milk.)

  • Try “club mate” (pronounced mah-tee). I am sure it contains more coffeine than most drinks although it usually contains a bit of sugar too.

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