Words of woo: what does ‘alkalise’ mean?


‘alkaline’ diets usually revolve around eating lots of fruit and vegetables – no bad thing, but it won’t change your body’s pH

If you hang around in the unscientific chunks of the internet for any length of time, as I find myself doing from time to time, you start to come across certain words that get used over and over. They are usually words that sound very sciency, and they’re being used to make things sound legitimate when, if we’re honest, they’re really not.

One such word is ‘alkalise’ (or ‘alkalize’). I’ve met it often ever since I wrote my post ‘Amazing alkaline lemons?‘. So, what does this word mean?

Good question. Google it, and at least the first three pages of links are about diets and how to ‘alkalise your body’ featuring such pithy lines as:

“It’s not really a diet… it’s a way of eating” (is there a difference?)
“Alkalise or live a life of misery” (gosh)
“Alkalise or die” (blimey)
“Alkaline water” (apparently this is a thing)
“Why it’s important to alkalise your water” (using our overpriced products)

In fact, I had to click through several pages of Google links before I even got to something that was simply a definition. (I’m aware that Google personalises its search results, so if you try this yourself you might have a different experience.) Certainly, there are no legitimate chemistry, biochemistry – or anything else like that – articles in sight.

Hunt specifically for a definition and you get turn basic and less acidic; “the solution alkalized”‘ (The Free Dictionary), to make or become alkaline. (Dictionary.com) and, simply, ‘to make alkaline’ (Collins).


pH 7 is neutral, more than 7 is basic

The first of these is interesting, because it refers to ‘basic’. Now, as I’ve explained in another post, bases and alkalis are not quite the same thing. In chemistry a base is, in simple terms, anything that can neutralise an acid. Alkalis, on the other hand, are a small subset of this group of compounds: specifically the soluble, basic, ionic salts of alkali metals or alkaline earth metals.

Since there are only six alkali metals (only five that are stable) and only six alkaline earth metals (the last of which is radium – probably best you steer clear of radium compounds) there are a rather limited number of alkalis, namely: lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, caesium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide and radium hydroxide. There you go. That’s it. That’s all of them. (Okay, yes, under the ‘soluble in water’ definition we could also include ammonium hydroxide, formed by dissolving the base, ammonia, in water – that opens up a few more.)

This, you see, is why real chemists tend not to use the term ‘alkalise’ very often. Because, unless the thing you’re starting with does actually form one of these hydroxides (there are some examples, mostly involving construction materials), it’s a little bit lead-into-gold-y, and chemists hate that. The whole not changing one element into another thing (barring nuclear reactions, obviously) is quite fundamental to chemistry. That’s why your chemistry teacher spent hours forcing you to balance equations at school.

No, the relevant chemistry word is ‘basify‘. This is such a little-known word that even my spell checker complains, but it’s just the opposite of the slightly better-known ‘acidify’ – in other words, basify means to raise the pH of something by adding something basic to it. Google ‘basify’ and you get a very different result to that from ‘alkalise’. The first several links are dictionary definitions and grammar references, and after that it quickly gets into proper chemistry (although I did spot one that said ‘how to basify your urine’ – sigh).

What does all this mean? Well, if you see someone using the word “alkalising” it should raise red flags. I’d suggest that unless they’re about to go on to discuss cement (calcium hydroxide is an important ingredient in construction materials) cocoa production or, possibly, certain paint pigments, then you can probably write off the next few things they say as total nonsense. If they’re not discussing one of the above topics, the chances are good that what they actually know about chemistry could safely fit on the back of a postage stamp, with space to spare, so nod, smile and make your escape.

For the record, you absolutely don’t need to alkalise your diet. Or your urine*. Really. You don’t.

And please don’t waste your money on alkaline water.


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There’s no good evidence that drinking lemon juice has a significant impact on urine pH.

* In the event that you actually have problematically acidic urine, perhaps due to some medical condition, there are proven treatments that will neutralise it (i.e. take it to around pH 7, which is the pH urine ought to be, roughly). In particular, sodium citrate powder can be dissolved in water to form a drinkable solution. Of course, if this is due to an infection you should see a doctor: you might need antibiotics – urinary tract infections can turn nasty. Yes, I am aware that the salt of the (citric) acid in lemons is sodium citrate, however there is no good evidence that drinking lemon juice actually raises urine pH by a significant amount. And yes, I’m also aware that dietary intake of citrate is known to inhibit the formation of calcium oxalate and calcium phosphate kidney stones, but that’s a whole other thing. If you have kidney stones there are a number of dietary considerations to make, not least of which might be to cut down on your consumption of certain fruits and vegetables such as strawberries and spinach (and ironically, if you look at some of the – entirely unscientific – lists of acid-forming and alkali-forming foods these are almost always on the alkaline side).

15 thoughts on “Words of woo: what does ‘alkalise’ mean?

  1. Pingback: A-t-on trop confiance en la science ? - Blog de Thomas Kowalski

  2. Thank you. Would love more info on this. I suffer with calcium oxalate stones and IC….the diet suggestions are often conflicting.


    • I’m definitely not an expert on the best diet to avoid kidney stones. Other than the obvious things of avoiding rhubarb, spinach and the like (which contain oxalates), I wouldn’t know what else to suggest. It might be best to ask your GP if you can be referred to a dietician?


  3. I came here because of ‘alkaline lemons’ 🙂

    And seriously, while I agree that the correct word is “basify” (though dictionaries from top of the Google list will say otherwise – most have a (pH >7) definition ), “alkalize” has some sense. Most of the tap water (by “tap water” I mean a mixture) will have a significant amount of alkaline/alakali earth cations (especially Na+, Ca2+, Mg2+), and if that tap water is basic , it contains OH- anions as well (in amount greater than H+). So, basifying the water can count as alkalizing it…
    Adding a baking soda to water is – in fact – adding a small amount of sodium hydroxide, due to carbon dioxide excaping the solution (expecially if you heat the solution afterwards). It can count as ‘alkalizing’.
    Also, take into account that the word “basic” in for instance “basic food” can have two meanings (simple food or alkaline food?) , so using “alkaline” will clarify the meaning.

    By the way, during my school, chemistry naming conventions changed twice. 🙂


      • Lye water. Broken eggshells used for neutralize too acidic food. Maybe (if ammonium compounds count) baking ammonia…

        There are little “foodstuffs” that are definitively “alkaline” (when I use “alkaline” in quotes it means “with added water have a pH greater than 7”; as I said above , “basic” can have different meaning) due to the fact we do not like the “alkaline” taste. Baking soda solution isnt pleasant do drink – and it is only mildly “alkalic”.

        So I would not disregard any article for using “alkaline” instead of ‘basic’. While I agree that most of “alkaline lemons” “alkalizing blood” etc articles are just a pseudoscience , picking up on a naming convention (correct by the way by at least few online dictionaries)) is a low blow in my opinion 🙂

        PS. For all alkaline-lovers: Want to alkalize your blood? Do 50 fast and deep breaths… congratulations, your blood is more alkaline now. How do you feel?…


  4. Another food for thought: How is the condition where blood pH levels are abnormally high, called?


      • Yes, but pH = negative logarithm of H+ concentration, so high pH = low H+ concentration , thus high pH is basically ‘basic’ not ‘acidic’ (pun intended).
        in other words: how is the antonym of acidosis called?


      • Sigh. Alkalosis. As you know. However, I wasn’t criticising the term alkalosis, which is a medical condition. My point, if you read the post beyond the headline, was that chemists don’t, usually, refer to ‘alkalising’ a solution. They talk about basifying it. It’s not a term (real) doctors use, either. Thus, if you find someone talking about ‘alkalising’ something, nine times out of ten they’re talking total bollocks.

        This is simply fact. You can argue semantics all day, but the fact stands: ‘alkalise’ is, with a few exceptions, a woo word.


      • Sigh. ‘Alkalosis’ is a proper medical term (by the way, you can assume there are ‘alkalis’ in blood – most soluble cations are either alkalis or alkali earth). So ‘alkalizing blood’ – as a ‘therapy’ that leads to ‘alkalosis’ is maybe a ‘woo word’ for a chemist, but actually have sense.
        And even for a chemist… the cations in blood are mostly alkalis and alkali earth ones. So, increasing blood pH can be named as ‘making blood more alkaline” or simply ‘alkalize’/’alkalinize’ blood’.

        Now – you give fuel for all alkaline diet lovers by stating that use of ‘alkalizing’ word is enough to disregard the article. While it may not be a perfectly correct term, it is used widely enough …
        The answer can be like ‘he is just picking on naming conventions, that does mean he don’t have better things to say’. And while you have much more solid arguments… well, they don’t aim for convicing you or others in fair discussion- because they can’t. But for winning the online quarrel?… It can work.


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