How many times have you heard someone say they won't feed synthetic minerals to their horse? Or that they only feed 'organic' minerals? Maybe you also think or say the same?

Well, I'm really really sorry about this, genuinely, but this is all a Big Myth, and we're about to blow it apart for you because ... synthetic - and organic - minerals, are the same thing. And before you think that this is a bit know-it-all on my part, my hands are in the air here too ...

For those of us who over the years have been hit round the head with feed and supplement brain-freeze, I think we can all agree on one thing – a horse has a very complex biological system, especially when it comes to … minerals.

I vividly remember back to around 2007/2008 when I took my horses barefoot, and the phrase 'mineral balancing' first hit our world. Those of us who were embarking on this new barefoot adventure experienced the trial that was blending our horses' minerals at home, or should I say attempting to. Back then I didn’t have a science-y cell in my body so all this science stuff was an absolute minefield to me – all those elemental mineral ratios gave me proper brain-ache. (No need to panic though - over the years since and with a ton of very intense studying, my brain's been retrained 😉).

But ohhh how I remember those unavoidable lungfuls of mineral dust-cloud amidst kitchen-bombsite as each week I'd line up bagfuls of various powders in front of numerous jars and labels, then attempt to blend a weeks' worth of minerals for 5 horses - yep, this is how we all did it back in the day! In the beginning it was an almighty mess, but I soon cracked it, then intensively studied it, and finally back in 2013, what had eventually become our EquiVita mineral balancer appeared on the website.

Cut to nearly a decade on, and these days we're all now clue'd up on the importance of mineral balancing being the nutrient foundation of any diet, especially as new data comes out by the day from the latest research. Which means ... practices/methodologies have had to change with the times.

Of course this is no bad thing as we advance our knowledge on how to care for our horses. And as I type, right now is no exception, because the latest research is now re-looking at what has, until now, been thought of as the gold-standard of minerals, namely chelated.

(🤓 Science Alert! 🤓 Chelation being the act of chemically bonding a molecule to an amino acid), which originally hit the headlines a few years back, and upon which all us equine supplement companies dove on to provide our clients with the then-best raw materials available.)

Specifically relating to copper and zinc, and selenium in a slightly different way, this new, very complex, laboratory-made, chelated mineral kicked the former commonly-used, and natural 'sulphate' version, well and truly into touch. Every equine mineral company abandoned sulphates quicker than a quick thing, and chelated soon appeared on every product analysis against the copper and zinc entry, and occasionally magnesium and selenium, usually with the words organic and chelated; selenium became organic selenium yeast.

Chelated minerals had two USPs (Unique Selling Points) - they were said to be more 'bioavailable', and they were 'organic'. The 'organic' USP really put the cat amongst the pigeons, because it suggested that chelated was a more natural, uncontaminated product, which made the former mineral type used, inorganic sulphates, sound chemical, synthetic themselves, and therefore rather undesirable.

Wrong! As it turns out, when it comes to minerals, the term 'organic' has a very different meaning to what we all think of when it comes to plants/veg/fruit. In mineral terms, organic is actually the chemical, made-in-a-lab chelated version; 'inorganic' is the natural mineral form, coming directly from soil or rock. So, in this instance, organic v. inorganic is completely the reverse to our normal way of thinking, unless you're a chemist, of course.

Then there was the alleged improved bioavailability claim - which as it turns out is very misleading, but we'll get to this further on. However, cut back to then, and who didn't love the concept of a super-clever new nutrient form in our mineral supplement getting into the body quicker? Allegedly ... 😉

So, let’s get stuck into the How & Why, and bring ourselves up to date with the current research. But first up ... before there’s an almighty outcry - can I just say that we're not saying that chelated minerals are either good or bad; what the data is showing is that this is more about the extra biological process that the liver has to go through to metabolise this particular form of mineral. As it turns out, it’s a right old faff, and makes the liver have to work much harder than it should, simply because it has to undo what humans have done to mess around with chemistry.

Let’s start at the beginning

In nature, minerals are usually in an inorganic form, while organic minerals simply don’t exist in nature, hence they're made in a lab. The two terms actually derive from chemistry itself - organic chemistry deals with everything built from carbon atoms (I know, horribly science-y, but stay with me - it gets more obvious); inorganic chemistry takes care of the rest.

Quick digress - wild horses absorb their minerals from different sources, but the main source is their basic food, i.e. long, dry, stemmy grasses, as well as barks, woody branches, fruits, nuts, berries et al. Example - grasses are usually rich in calcium, because grasses absorb calcium easily from the soil and use it for their own scaffolding. Hence, when we get our grass and forage analysed, the report will show the natural, inorganic nutrient deficiencies.

Put simply, inorganic is what we see in the wilds of the natural world; limestone (calcium carbonate) is an inorganic compound that is broken down in open-cast mining; oxides and sulphates are also found in nature, such as our old trusty friends, magnesium oxide, and copper/zinc sulphate. Organic is where scientists have tweaked it, and added – attached - something on to the mineral - in the case of copper and zinc it's an amino acid, a very un-natural connection, and as it turns out for the liver, a lot of extra work on an already overloaded schedule, to undo to get to the actual mineral hidden away beneath the amino acid.

There's no denying it's not awesomely clever, but either way, and here's the important bit - it's not the form that the body naturally recognises, and evolution, our old friend in our horse world, has optimised the horse's digestive tract to only recognise natural, inorganic - as in, derived from nature - minerals.

And herein lies our problem. The horse’s gut only recognises the chelated mineral as an amino acid (a broken-down protein), and not the mineral itself which is hidden away within the protein which in essence is acting as a trojan horse, so it’s sent off to the liver as a protein. The liver then gets confused because it too only sees the amino acid as a protein and not a mineral, so metabolises it as a protein. So, these chelated, aka made-in-a-lab minerals, immediately add to the workload of the liver, which is already under a ton of metabolising-toxins strain as it is.

This is it in a nutshell - the gut and liver don't recognise a chelated mineral as a mineral, full stop. But let’s dig a little deeper into what actually happens cos there’s even more to it.

We'll start with the gut receptors, because this is where it all starts

The big difference isn't so much with the manufacturing process (although by their very nature, organic compounds are usually more complex and therefore more expensive to manufacture) but how the horse's small intestinal gut receptors recognise/absorb the mineral.

Minerals don't simply slip through the intestinal wall any-old-how. In the small intestinal (SI) wall membrane, where the main digestion/absorption processes happens, there are special receptors - highly specialised cells with transport molecules on their surface - to which minerals selectively tie (the same function applies to vitamins, sugars and fatty acids). These transporters are always nutrient-specific, ie zinc is only absorbed by zinc transporters, copper only by copper transporters, and so on.

These receptors recognise what minerals the body needs, i.e. they see copper, and if the copper stores are empty, they know to actively absorb and store the copper. If they say ‘No ta, we’ve got enough,’ the mineral stays in the digestive tract and passes on through with the food waste to be eliminated with the poop at the end of the journey. If this didn't happen and copper was continually absorbed, it would have to be laboriously filtered out of the bloodstream via the kidneys and out in the urine.

So, you can see that what we have here is a wonderfully simple, biologically natural, in-built self-selection process, happily regulating the absorption (and excretion) of the various nutrients, taking what it needs when it needs it, and not overloading itself with what it doesn’t need.

Now, back to those chelated minerals ...

... bound to those amino acid proteins,and here's where it all goes horribly wrong.

The mineral gut receptors don’t recognise the chelated mineral because it's not in its natural mineral form, so they're ignored. Instead, they're recognised and absorbed by the amino-acid/protein transporters, so the mineral therefore enters the bloodstream as a blind passenger on a protein. Cue Problem No. 1 - straight away we've bypassed the clever self-selection process re how full, or empty, the body's stores are for that particular mineral.

Once it gets to the liver, the liver then finds that this amino acid is a defective protein because there’s a mineral in it where it shoudn't belong. Problem No. 2 - the liver not only can't utilise the amino acid the mineral came in on, but it now also has to degrade the defective protein to get at the mineral to release it back into the bloodstream. Meanwhile, the amino-acid debris has to be sent off to the kidneys for elimination.

A right old round-the-houses pallava. If the horse's body needs the mineral it’s a lot of extra work for the liver, which is already working hard enough, and now with these minerals hidden in a protein, it has to work even harder.

But - it's not just a significant extra burden on the liver; the kidneys are now involved as well - Problem No. 3, because they also have to eliminate the mineral if it’s superfluous to requirements (because it's too late to find its way back to the gut system and out via the poop), plus there's extra urea - which is the waste product when amino acids are broken down - which isn't great news as higher urea levels disrupt the microbiome, and we all know about that! So a right old pallava indeed. Which links us nicely to ...

More bioavailable?

Meanwhile, back to the improved 'bioavailability' claim, the key USP for chelated minerals, and yes, there's a twisted truth here; chelation, the act of chemically bonding a molecule to an amino acid, increases bioavailability, as the aim is to mimic chelation in nature so the body recognises the mineral supplement as 'food' rather than a mineral molecule. The result is said to be increased absorption. Yes I know that was a bit of a mouthful - read it twice and it should become clear-ish - it's kind of all centred around the word 'food'.

To quote from "Death by Default", by Doctor E Jackson Stockwell:

"If you were to take a metallic calcium molecule that is only 5% absorbable and coat it with a protein molecule, then introduce it into the digestive tract, the walls of the small intestine thinks it's a protein and absorption increases (because it thinks it's a 'food'). Chelated minerals = more bioavailability."

But - now we're going to throw that theory under the bus, because ... bioavailability simply means the time it takes for absorption into the bloodstream. That’s it. No further. Only as far as the bloodstream. It has nothing to do with what happens thereafter, as in how well the body's cells can use the mineral; it only describes the increased levels of the mineral in the blood after the absorption intake of the mineral. Which I think we’ve already established isn’t what’s happening here.

This is why the term bioavailable is misleading - remember that sorry little mineral that came in as a blind passenger on a protein, then got chucked back into the bloodstream once the protein was blown apart? And remember that if the mineral stores were full, it wouldn't have been absorbed anyway? This is why bloods show high measures of minerals in the bloodstream when they shouldn't be there anyway, because they've come in via organic chelation.

Which links us nicely to selenium

Again we have the same scenario, except it’s a little more vital to get this one right as there’s a very fine line between safe selenium intake and selenium toxicity.

Selenium’s organic, chelated form is known as selenium 'yeast'; its’ inorganic (and therefore natural) form is sodium selenite (this is what we include in our EquiVIta composition).

So, as before, the liver meets the tweaked selenium, usually attached to either cysteine or methionine amino acids. Gets a bit science-y now but hang in there as it all comes out in the wash, promise, and it's only one sentence long. Stand by your guns - here we go - 🤓 Science Alert! 🤓 ...

Cysteine/methionine are usually bound to sulphur in a specific position, which stabilises the protein structure, but the protein can only work when this 3-dimensional structure is fixed, which is only completed by that sulphur bond. I know, I know ... read it again, rinse and repeat. And a bit like the chelated copper and zinc, when the liver doesn’t see the sulphur and sees selenium instead, it recognises it as … our new friend, an unstable protein!

But - here's where selenium is now different to copper and zinc. The liver doesn't know what to do with these particular unstable proteins so instead of sending them on to the kidneys for excretion, it sends them out to the cellular tissues to be stored.

Here's the thing - it can take a year for these proteins to be degraded - seriously - up to a year for these proteins to be degraded. So they remain in the body, unused, for a very long time, which risks considerable excesses of selenium being stored in the tissue, meaning there's now the risk of subclinical selenium toxicity bubbling under the surface, which apparently can only rarely be detected via bloods.

How do we see the effect of this? Typically we'll see this in the hooves – we know both cysteine and methionine as important proteins to build hoof wall/keratin and body hair, but when you feed chelated selenium it's been noted that the hoof capsule's quality changes. The hoof wall becomes weaker/softer, as well as being behind multiple hoof abscessing, white line disease, and a brittle mane/tail that breaks. And all because there’s selenium encapsulated in the protein when it should be sulphur.

The take-away message here is that it's absolutely not advisable to supplement the diet with organic selenium, and only replenish the deficient selenium requirement with inorganic selenium - sodium selenite - in the mineral feed.

To conclude

So now we get to the potential backlash.

Of course there will be some that say they've been feeding chelated for years and their horse is fine. There'll be others that say that the associated liver stress hasn't been well documented, or that chelated minerals behave like inorganic minerals anyway.

As for selenium yeast, again some will say there's no more danger of toxicity than with inorganic because with selenium it's dosage dependent, and that subclinical (aka asymptomatic) toxicity is a meaningless claim unless toxic levels are confirmed by blood work. Thing is though, like chelated copper and zinc, the selenium in bound in the protein, hidden like a Trojan Horse, so bloods won't show selenium levels, just the proteins.

For me this has to be a no-brainer, and with my EquiNatural hat on, the clue's in our name - we are nothing if not as natural as we can be, and this is no exception. Evolution has made the gut receptors only recognise the natural, inorganic mineral form and they know whether the body needs it or not, which means evolution’s design for the horse’s natural gut:liver function operates as it’s meant to. Whereas ... chelated minerals mess with the body’s biological metabolism and confuse the whole process, putting extra work on the liver and kidneys, as well as risking dysbiosis in the microbiome.

And, lest we forget, chelated minerals also provide a lot less mineral for your buck - they provide much less elemental mineral compared to the sulphate form, so we need to feed much more of it, and they're considerably more expensive so the overall cost of the balancer is higher. Sulphates go a lot further, so your balancer lasts longer, and is cheaper with it.

To conclude, and in my humble opinion, In order to ensure a natural, evolution-appropriate absorption of what's needed into the bloodstream to then be utilised directly by the cells, thereby avoiding stressing the liver biotransformation process and the already fragile equine metabolism, inorganic natural minerals in sulphate form have to be the better choice.

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Courtesy of Dr Christina Fritz / Feed Your Horses Fit workshop, 2021.