Management Partners:

Where I buy chelated calcium, B1, reishi,  pea protein, and some herbs:

Where I buy herbs, seeds, and tinctures:

PSSM Diet – An Individual, Research Backed Case Study on Feed Regimens, Feed Triggers, and More!

PSSM diet, PSSM management, PSSM exercises

Original PSSM diet posted 1/14/18 –

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Jax’s PSSM Diet: 2 months after diagnosis and proper PSSM1 management started, Oct. 2016, Photography by Karin

The Ultimate 2023 PSSM Horse Supplements List: A Full Year Tested As Of Writing This With No Signs Of Changes Needed

Base PSSM Diet:

  • 1-2 teaspoons of my calcium gluconate, reishi, and Vitamin B1 mix
    • Calcium gluconate takes the place of Lam Essentials (the chelated calcium only – I’m trialing him off a full vitamin/mineral supplement to see how he does, as it’s worked well for him in the past). ( Bulk Supplements Website )
    • Reishi takes the place of ImmuBiome products, specifically Focus, and has been an amazing addition for Jax (it’s also said to be good for anemia). ( Bulk Supplements Website )
    • Vitamin B1 has always been helpful for Jax, and I’m now buying the powder version to avoid fillers. ( Bulk Supplements Website )
  • 1-2 cups carrot and celery slices at a 2:1 carrot:celery ratio (approx. 1 medium to large carrot and 1/2 celery stick)
  • 1-2 tablespoons of pea protein isolate for flavor ( Bulk Supplements Website )
  • 1-2 tablespoons chia seeds
  • Various herbs as needed
  • Anemia: Jax gets one human dose (65mg) pill of ferrous sulfate daily. His RBC count and energy levels have improved on this amount, and start to drop if I don’t feed it.

The mix is at a 12:8:2 ratio:

I mix at 12 parts calcium gluconate, 8 parts reishi, and 2 parts vitamin B1. I usually use a random supplement scoop that I have laying around, and mix a bigger batch so I’ll have it for a few weeks (depending on how many horses you’re feeding – I’m giving this mix to my two plus a friend’s neurological horse, so it lasts a few weeks for three horses).

I’m currently feeding 1.25 teaspoons to all three daily as of Feb. 2023. I raise or lower amounts as needed – I found that winter requires a bit more than summer, but mine horses do really well in summer; this may be the opposite for PSSM horses or others that do better in winter.

This PSSM horse diet is anti-inflammatory and geared toward Central Nervous System health. Continue reading below to see how I came up with this PSSM diet that also works on neurological horses, and see this post on the different approaches to feeding a PSSM horse.

Changes needed in 2023 for navicular:

The PSSM portion of Jax’s diet above is still doing great for him, however, his mild navicular has caused a spur, and he now seems to need more protein and joint support. He still gets the diet above but we’ve added:

  • SmartPak’s SmartGain
  • 1/3 cup of pea protein
  • Tri Aminos
  • SmartPak’s Arthroxigen (for joints)

Jax is no longer anemic and is off iron supplementation. He’s getting Animed Tie-By for vitamin E and further support for his muscles due to being semi-retired from his navicular issues (he’s improving daily, and will hopefully come back into light trail riding at some point). His head shaking got bad in Spring 2024, and with the SmartPak’s I’ve been able to add ImmuBiome back into the mix:

  • 1/2 dose ImmuBiome Lean Muscle
  • 1/2 dose ImmuBiome Breath
  • Full dose ImmuBiome Spine & Nerve
  • 1 teaspoon magnesium gluconate from Bulk Supplements (seems to help spring issues including spring head shaking)

Mid-2021 Through The End of 2022: Jax, are you serious? More PSSM diet changes!

One day, I’ll type up a PSSM diet check list that works for Jax, and I’ll be able to leave it alone for at least a year – but that day is not today! We had a metabolic setback in summer and autumn of 2021 – complete with weight gain, sheath swelling, stocking up, and left front lameness with ANY feed that may have added to his inflammatory condition. Beet pulp and rice bran were no longer acceptable and, while the supplements listed below were very much needed, I couldn’t find a base feed to get them in him!

Thankfully it’s the end of February, 2022 right now as I type this, and we’ve worked through some things. He’s doing well on a base of carrots and celery – literally the only thing he handles on a daily basis. I have several ideas running through my head on why the previous PSSM diet stopped working:

  • He now absorbs nutrients properly from his ImmuBiome supplements, so at this point, less is more (he’s an incredibly easy keeper now, to the point I think he needs 10 miles a day to keep weight off!)
  • Cushing’s has been on my radar for some time now (see his herbal supplements in the last PSSM diet). I think, at the very least, he has an endocrine/cortisol issue, even if it’s not full-on Cushing’s. [Update 12/22/22 – it’s not PPID/Cushing’s! His metabolic numbers were beautiful when tested!]
  • Jax is 15 this year, and arthritis could be creeping in. The fact that his lameness and reactions seemed to be inflammation-triggered leads me to a bone condition like arthritis or navicular. [Update 12/22/22 – he’s not triggered in the least since taking him off flax! So arthritis and acute navicular pain are no longer on my radar, for now!]
  • Most importantly, last year we had a bumper crop of acorns, and the big turd was gorging on them! Getting him in the drylot and away from acorns helped immensely, but he still can’t handle his previous base feed.

I’ve also done recent blood tests and x-rays on Jax’s fronts and found flat coffin angles, mild navicular on right front (the sound hoof), no dropping of coffin bone, and decent sole thickness (leading my vet away from the idea of Cushing’s).

On pulling bloods I found a few interesting items, but mainly anemia! Regular blood building supplements weren’t helping, so after some research I found two things that could help: 1) learning that Cushing’s can cause anemia, and 2) reishi mushrooms can help anemia (thanks to Chris at ImmuBiome, who’s amazing at helping with these sensitive horses – see my ImmuBiome product reviews here).

Jax’s current PSSM diet is focused on calcium signaling, Cushing’s, and anemia:

  • 1/4 – 1/2 cup Triple Crown ground flax [Update 7/30/22: we’ve found another feed trigger – flax causes hoof sensitivity and caudal hoof failure! There can be a link between feed allergies and anemia, so I’ll be testing blood in a couple months to see if removing flax helps the anemia issues.]
  • 1/4 – 1/2 cup pea protein from Bulk Supplements ( Website )
  • EquiFeast Lam Essentials
  • ImmuBiome Focus (has reishi)
  • 1-2 cups carrot and celery slices
  • SmartPak B1 pellets
  • SmartPak Smart Pituitary (Jax’s Cushing’s numbers are amazing, so we’ve stopped this supplement)
  • SmartPak DMG (didn’t do much, so I’ve stopped this one)

[Update Feb. 2023 – SmartPaks don’t work long term. I suspect binders, and I think that’s the same reason hay pellets don’t work for him.]

I soak the ground flax until it gels, then add supplements and veggies. It makes a gravy-type consistency with the supplements, and Jax loves the taste of flax and pea protein so it works. B1 helps nerves and calming, and between that, Focus, and Lam Essentials I’m seeing no signs of head shaking (before he was on several Immubiome products plus EquiFeast Fight Back for head shaking).

He is calm right now, with a happy look and, finally, eager to move out and go forward again (he’s been lacking forward for at least a year now). I’ll be pulling bloods again soon to see if our anemia issues are in check, and if they are then this PSSM diet won’t change any time soon (hopefully)! I’ll be posting soon about our recent hoof issues as well, which I think I’ve also got a handle on, thankfully.

Small PSSM Diet Shift July 2022 After Finding That Flax Is a Feed Trigger:

Jax refuses his Lam Essentials and ImmuBiome products without flax in his new PSSM diet, so I’ve altered for essentials while making the supplement load as small as possible. I’m mixing these items from Bulk Supplements: calcium gluconate (chelated calcium), reishi, and vitamin B1, in a 6:4:1 ratio and feeding 1-2 teaspoons daily, depending on weather (he needs higher amounts in colder weather). I’ve also found that spirulina helps stop sweet itch and other allergy issues (fly and tick bites also don’t swell as badly now).

I’ve tried this mix in the past while he was still on flax, but it didn’t work – symptoms would creep in about 2.5-3 weeks after being off Lam Essentials. Tight back and difficulty putting his head down are the first issues I’d see, along with spooking and anxiety. This time around (without flax triggering issues) it does seem to be working, so my fingers are crossed!

I buy almost all of his current PSSM diet supplements from Bulk Supplements, and you can get them from either their website or on Amazon. His total current PSSM diet is:

  • 1-2 teaspoons of my calcium gluconate, reishi, and Vitamin B1 mix
    • Calcium gluconate takes the place of Lam Essentials (the chelated calcium only – I’m trialing him off a full vitamin/mineral supplement to see how he does, as it’s worked well for him in the past). ( Bulk Supplements Website )
    • Reishi takes the place of ImmuBiome products, specifically Focus, and has been an amazing addition for Jax (it’s also said to be good for anemia). ( Bulk Supplements Website )
    • Vitamin B1 has always been helpful for Jax, and I’m now buying the powder version to avoid fillers. ( Bulk Supplements Website )
  • Occasional: 1/4 teaspoon of a spirulina for allergies (too much makes him silly)
  • Occasional: 1/4 teaspoon Jiaogulan ( Bulk Supplements Website ) and 1/2 teaspoon Cissus Quadrangularis ( Bulk Supplements Website ) for tendon health. CQ and Jiaogulan are huge in helping with my chronic tendon issues, and they seem to help Jax as well. For more on my experience with Cissus Quadrangulari click here.
  • 1-2 cups carrot and celery slices at a 2:1 carrot:celery ratio (approx. 1 medium to large carrot and 1/2 celery stick)
  • 1-2 tablespoons of pea protein isolate for flavor ( Bulk Supplements Website )
  • 1-2 tbsp chia seeds

I plan to work the supplements down to the chelated calcium, reishi, and B1 mix only for the most simple PSSM diet possible; but for now I’m seeing signs of tendon stress so those supplements are staying in the mix, and Spirulina may be something we need to keep for ongoing allergy maintenance.

This PSSM diet is cheap and easy, and he’s been on it for approximately a month now – I should be seeing signs very soon if being off Lam Essentials isn’t going to work.

Jax’s topline is still going strong, even though he’s off ImmuBiome products completely now. It seems that he’s too easy a keeper on Lean Muscle now, and thankfully, the reishi alone seems to be doing well for him.

Small PSSM Diet Shift December 2022 as Anemia Issues Still Persistent:

The basic PSSM diet has stayed the same, but I’ve added some SmartPaks. It appears the reishi and moringa aren’t helping the anemia issues, and while spirulina does really help allergies, it’s starting to trigger spookiness so can only be fed occasionally. Jax’s tendons are doing great at this time, so he no longer needs Cissus Quadrangularis.

Jax did well on SmartPituitary for extra antioxidants in the past, so he’s back on that as a potential replacement for spirulina (he’s off all herbs I had listed above except reishi, as it’s likely maintaining his gut). He’s also on Metaboleeze, which includes iron proteinate, to try to shift this anemia issue and it seems to be helping his energy levels. His hooves are still trying to improve from caudal failure while on flax, so he’s also on Focus HF.

Jax’s demeanor and work effort are beautiful on this current iteration of his PSSM diet – he’s not spooky and he’s his forward, happy self. Metaboleeze does have some flax in it, so I’m watching for any hint of lameness and hoping the Focus HF will balance out any negative effects from this small amount of trigger feed (Focus also has a small amount of alfalfa, another of his triggers). I’ll update this section as I have more info on how these things are affecting him.

Early 2021 through Mid-2021 – Jax’s PSSM Diet now balances his electrolyte issues!

A quick update (November 23) on our revolving door of PSSM diets (lol) and our recent calcium and anxiety issues (click link for a detailed look at our switch to chelated calcium and trialing other Immubiome products)! We started EquiFeast’s Lam Essentials and… it’s amazing! Calcium carbonate did the same things in the beginning, but issues started cropping up like spasms in his chin (electrolyte issues always trigger face spasms, so this showed me something was wrong with electrolytes) and mineral buildup in his kidneys – so calcium carbonate had to go! Jax’s current PSSM diet looks like this:

  • 1/2 cup Triple Crown rice bran
  • 1/4 cup Triple Crown ground flax
  • 1/4 cup pea protein isolate (for flavor and extra aminos) ( Website )
  • EquiFeast Lam Essentials (vitamin/minerals)
  • EquiFeast Fight Back (for head shaking)
  • ImmuBiome products (this needs more explaining lol!)
  • Handful of chia seeds on occasion
  • Herbs: Jioagulan, Chaste Berry

ImmuBiome products – I have a love/hate relationship with them: I love them and I hate that I can’t stop buying new ones to try lol. Jax does amazing on Lean Muscle, but I don’t feel he needs it daily anymore. However, removing it completely seems to cause topline loss, and adding it back brings topline back – so it has to stay in the rotation.

So I’ve started alternating his supplements (including his EquiFeast supplements): 1/2 scoop of Lean Muscle (leaky gut) and Spine & Nerve (head shaking) on days I feed Lam Essentials, and 1/2 scoop G-Tract (ulcers, hindgut) and Strength & Stamina (laminitis, joint/tendons) on days I feed Fight Back (head shaking). He gets Immubiome Breathe thrown in for a few days if he has a cough or snotty nose and as a boost to Fight Back for allergy relief. This gives me a head shaking supplement everyday and allows his feed amounts to stay small.

This year we fought some serious metabolic issues and he spent the entire summer lame. I’m still up in the air on the complete pathology of this lameness, but I know there were some triggers in our wooded lot that aggravated this issue (acorns and honey locus pods). Even though he’s sound now as of this update thanks to a few weeks in the drylot, I’m still going easy with hard feed, just in case.

Jioagulan and Chaste Berry are for metabolic support and were added after he went lame this summer (and they did seem to help the lameness, cresty neck, and he even developed sheath swelling this year which these herbs helped). I’m not sure why he went full-on metabolic this year, but I’ll update (and maybe add a post) as I figure this out a bit more.

A quick note on beet pulp: it started playing into his metabolic issues this year. As we get further into winter I may add a bit of beet pulp back in and see how he responds. This year he’s back to full-on easy keeper status, there’s no muscle or weight loss (and at times he’s been a bit too hefty) so this may just be a case of him no longer needing the calories.

While the previous PSSM diet was simpler, there are some things chelated calcium did that calcium carbonate didn’t: it fixed what looked like a vertigo/dizziness issue when he put his head down, and his muscles are like jelly even on days he isn’t worked. I can pull him from the field after a couple days off and ride 3 miles instead of hand walking .5 mile. And the anxiety is GONE. So, not as simple as far as PSSM diet, but so worth the results. I don’t know how long this will last, but I’m loving his muscle and mental health at this time!

Late 2020 to Early 2021 – Jax’s PSSM Diet is Simple and Can’t Be Categorized as a “PSSM Diet”

As of August 2020, Jax stopped handling the diet below. See my update on that section for the very good reasons why! However, to show that he was no longer handling this he almost tied up in work – twice! So back in August this didn’t look like a good thing. The only supplement I brought forward from the old diet was calcium carbonate. Here’s his new diet:

  • 1-5 lbs Beet Pulp (depending on work levels, but has slowly decreased to less than 1 lb over time)
  • 10g calcium carbonate
  • ImmuBiome Lean Muscle
  • St. John’s Wort and Valerian in human doses (SJW 1/2 dose)

And that’s it for his daily regimen! He gets other misc. herbs/seeds on occasion but this very simple “PSSM” diet is our new normal! He’s also eating less hay – last winter he was gorging on 30-35 lbs daily, this year 20 lbs daily is enough to keep him happy and healthy – a drastic change for this boy. I credit this to the ImmuBiome and a possible past leaky gut issue.

I’m kicking around the idea that P2 was triggered by a malabsorption issue – caused by leaky gut – and leaky gut potentially played in his electrolyte issues as well by letting them leak straight through the gut barrier, affecting his blood mineral levels. An intensive deworming in early 2021 to be sure we had no gut perforation due to parasites was the last step in normalizing some of our electrolyte and other issues. I should add that as of writing this, his topline is better than it’s been since he went symptomatic 6 years ago!

I should note that I’m getting ready to trial EquiFeast’s Lam Essentials – I’m unsure of a couple of things with calcium carbonate and am suspecting oxalate issues behind his high calcium needs. You can get chelated calcium from sources other than EquiFeast supplements – such as Calcium Gluconate from Bulk Supplements, which is something I may try in the future if I find the Lam Essentials doesn’t work for Jax.

Late 2018 to Late 2020 – The Muscle Building PSSM Diet that Worked for Almost 2 Years!

There have been so many PSSM diet and management changes and new things discovered these past 2 years!  First, Jax has been further diagnosed – he’s n/P1, n/P2, n/Px – meaning he’s not just PSSM1 (See Jax’s Story for more on these genes).  He’s also PSSM2 and has a gene associated with RER, meaning that his previous Type 1 PSSM diet was too low in protein (P2) and was not geared towards RER/Px in any way (other than the cool energy source of Renew Gold). Jax has been on his current PSSM diet for over a year and has been thriving on it:  

  • 1 lb Renew Gold (fat for P1 and protein for P2)
  • 2 cups pea protein (for P2 – I use Pea Protein Powder from Bulk Supplements)
  • 1 cup chia seeds (high omega 3 fat for P1 and protein for P2)
  • AZ Copper Complete
    • Flax base has fat and protein with high omega 3
    • Has 3 limiting aminos (lysine, methionine, and threonine) for P2
    • Fat is a cool energy for RER
    • Chromium specifically helps RER horses
    • Mag and Vit E
    • So many more positives!
  • Horsetech’s MMX (extra B vitamins and mag)
  • Horsetech’s Gutwerks
  • Up to 2 extra tbsp of mag ox (this would later be removed due to causing spookiness)
  • 1-4 tbsp iodized table salt depending on season/sweating
  • Up to 2 tbsp of baking soda, though he doesn’t seem to need as much now that he’s on Gutwerks
  • 24g of added calcium – started with Uckele’s Equi-Cal, now using Horsetech’s Calcium Carbonate as it contains no fillers. You can also get Calcium Carbonate from Bulk Supplements.


  • Jax also get herbs and whole foods now, and he’s doing great on them!  These include pumpkin and sunflower seeds, 1 medium carrot, 1 stalk of celery, up to 1/4 cup of pumpkin flesh or a small square of pumpkin rind.  Jax gets small amounts of MSM (around 10g) on occasion.

Jax has issues with electrolyte imbalances which his PSSM diet has to account for, and every late winter to early spring he seems to have hyperkalemic (high blood potassium) and hypocalcemic (low blood calcium) symptoms.  Because of this, his PSSM diet also follows fairly close to an HYPP diet, including a handful of oats (less than 1/3 cup) on occasion to cause an insulin spike and pull potassium back into the cells (I know, CAUSING an insulin spike is not part of a Type 1 PSSM diet!

However, this works in this instance – but trial this with extreme caution).  His PSSM diet does change during this time of electrolyte upset, and I limit his whole foods and herbs, Renew Gold, AZ Copper Complete as they add to the potassium load.  Read more about that here.

Update February 2021: I believe this PSSM diet stopped working last August for two reasons. 1) High protein, high calcium, high magnesium Timothy hay – we found a hay that perfectly fits his needs! And 2) He’s past his protein deficiency! Basically this diet didn’t stop working – it did the job I needed it to do, and he stopped needing it! Our current hay analysis:

Early 2018 – We Have Our Base PSSM Diet! Still Working Out Specific Supplements.

UPDATE 2/27/18! I’ve found a supplement that has most of the things that I was supplementing separately below.  His new PSSM diet is:

  • 1 lb Renew Gold
  • .5-1 lb Copra
  • .5 lb Beet Pulp with molasses (soak/rinse/soak method)
  • 1 cup Chia Seeds
  • 2 tbsp Salt
  • 2 tbsp Mag Ox
  • 2 tbsp Baking Soda
  • 4 oz Uckele Sport Horse Grass (new addition)
  • Will add Uckele Tri Amino if needed.
  • For now, canola oil has been removed, may add back if additional fat needed.

Update – Beet pulp seemed to be a huge no and head shaking and exercise intolerance became a serious issue on this diet – these together are typically signs of high potassium.  Since beet pulp is a low potassium feed, but molasses is very high potassium, I assumed the soak/rinse/soak method didn’t work for removing potassium residue from molasses. Otherwise, this PSSM diet did fairly well for Jax, and he did slowly start improving.  However, he’d plateau and go downhill for no reason on occasion, and it always took quite awhile for him to come back from it. 

I now understand that he was having Negative Nitrogen Balance issues – he wasn’t taking in enough protein to keep his muscles from catabolizing, so he kept losing muscle and going symptomatic with small sicknesses or other stress (in other words, his PSSM diet didn’t focus on P2, which caused these issues).  I had to remove the Sport Horse Grass as they stopped making the powder form (granule form had added iron and other things I didn’t want).  He improved going off the Sport Horse Grass, possibly due to the additional potassium in it. Update (again): The copra (over 2% potassium!) was the issue, not the beet pulp!

2017 – Testing Phase – Trialing Individual Ingredients To Find Exactly What Jax Needs.

Jax’s INTENSE PSSM diet – when we were tweaking amounts and finding everything he needed and didn’t need – so, this is a pretty big list of supplements and feeds lol.  Notice that many of them are single ingredients.  Basically, the Renew Gold is the base of our PSSM diet (it’s not a ration balancer, and doesn’t contain a full spectrum of vitamins/minerals), and I add ingredients that seem to help.  If I ever find a supplement that replaces these things with numbers that I like, my life may become a lot less complicated!

Notes About My PSSM Horse Supplements:

  • PSSM Horse Supplements: Magnesium Oxide – There are many different types of magnesium.  I use mag ox as it seems to help and is very affordable.  At one point, I tried taking him off of the mag ox for about 2 weeks, and he became extremely spooky and started having mild spasms again.  Immediately after putting him back on the spasms stopped and after a week or so the spookiness started to subside.  Update: after a few years on magnesium supplementation he can no longer handle it as of 2020. Part of this is my hay which is high magnesium. But I’m speculating that adding magnesium over a long period of time may have repercussions.
  • PSSM Horse Supplements: Baking soda – some anecdotal evidence led me to try baking soda.  It’s used on race horses that tie up (given as a “milk shake” in very high doses which is NOT recommended) and seems to prevent tying up and spasms.  Jax has not had any episodes since starting on baking soda, even with the small doses that I’ve given (between .5-1.5 tbsp).  He was in the middle of a two week episode caused by abscessing hooves when I started him on baking soda, and it quickly stopped the spasms (after abscesses blew) and he began exercising to a much higher level immediately after.  Here’s a great link that has other minerals that are good for healthy hooves and healthy horses: Update February 2021 – Jax was on baking soda for about 3 years and it was huge for him and a necessary part of his PSSM diet. As of early 2020 he stopped needing it, which I see as a very good thing! He still gets baking soda on occasion.
  • PSSM Horse Supplements: Vitamin E – many of these horses need higher doses of Vit E (up to 10,000 IU), but Jax gets spooky on anything over 4,000 IU, and does best around 2,000-3,000 IU at most (sometimes is best completely off supplementation). Currently, he is off Vit E, though he occasionally gets up to 2,000 IU just to make sure his levels don’t decline.
  • PSSM Horse Supplements: B-12, VisionCalm, baking soda – Jax seems to get touchy around his flanks and sides sometimes after an episode.  My reading has lead me to the conclusion of hindgut acidosis.  B vitamins are made in the hindgut and usually don’t need supplemented, but my theory is that if the hindgut is compromised, the B vitamins may be lacking.   I started supplementing them any time he got a little touchy or spooky, but I now keep him on them full-time.  The baking soda (see notes above) seems to help the acidosis issue.

The most important thing to remember when building a PSSM horse diet is that excessive sugar will cause P1 horses to store excess glycogen that they can’t use which will lock up their muscles (especially if they’re not in good physical shape – see my post PSSM Science, Theories, and Treatment Ideas).  Spring grass, sweet feeds, regular feeds (many feeds advertised as “Low NSC” are too high), and even some hays are too high in sugars to keep many P1s from having symptoms. 

A good general guideline is to keep total NSC around 10% or lower (read also my post about glycemic index); and they need an alternative energy source. That said, as mentioned above I use oats on occasion in my PSSM diet to stave off potassium issues – so “too high” NSC is very individual, and depends on a LOT of things!

All PSSM horses are different, and therefore the PSSM diet and PSSM horse supplements that help each will be different as well.  Use this information to help guide your decisions, tweak amounts and products, and find the PSSM horse diet that works well for you. See the different approaches to PSSM horse diets here.

It is estimated that about 50% of PSSM1 horses can be helped by a PSSM diet alone.  Up to 90% of PSSM1 horses can lead a more “normal” life with a proper PSSM diet and exercise. (REFERENCE: MSU/Dr. Valburg article on PSSM1).  I suspect that the 10% that can’t be helped with PSSM1 management have extra genes like Jax – and though PSSM1 management won’t fix them, a hybrid management and hybrid PSSM diet might!

Other things that I’ve tried with Jax, and have removed from his PSSM diet for various reasons:

Past Horse Diet Trials:

  • Sweet Feed – Before I knew he needed a PSSM diet. I’m unsure of the brand, this was the feed-of-choice at my boarding facility.  Jax lost weight, and became a hard keeper, so he was put on “grain”.  He stayed a hard keeper, and eventually (after a year or two) started having PSSM symptoms.
  • Strategy Healthy Edge – 17% NSC – switched to this feed as it was the alternative to the sweet feed.  He did much better on this, but wouldn’t come sound.  Still no diagnosis, still not a safe PSSM diet (though some PSSM horses do well on it!).
  • Alfalfa pellets/cubes – These are an amazing base for a PSSM diet if your horse can handle them! Started on these right before diagnosis.  He did well on these for about 4-5 months, then he started becoming very stiff and tight muscled.  I started feeding him before work, and realized he was having mild spasms about 10-20 minutes after eating alfalfa.  I’m not sure if he was reacting to high potassium levels, if he had a deficiency that was met and then amounts exceeded… I don’t know why it stopped helping and started hurting him, but he can’t tolerate any alfalfa now.
  • Alfalfa/Timothy cubes – before I realized that alfalfa didn’t work (but I was starting to suspect problems) I tried these mixed cubes – he did terrible on this for the few days he was on it.  The brand I was using didn’t have a guaranteed NSC, and I think I may have gotten a high NSC batch. Update 2020: Plain timothy pellets don’t work either! However, compressed timothy bales from the same company work just fine – so perhaps the issue is the binder?
  • ADM StayStrong 33 – He really seemed to do well on this feed, but it kept getting back ordered so I decided to try something that was in stock.
  • ADM Metabolic Pellets – He was never “amazing” on this feed, but it didn’t seem to hurt and was good for mixing supplement.  Just like with alfalfa, he started having mild spasms after doing okay on this feed for 4-5 months so I removed it. He may have an issue with soy.  
  • ADM Healthy-Glo – I tried this feed the base of our PSSM diet when Renew Gold was back ordered for a couple of weeks – it started out okay, but after about 3 weeks Jax was not doing well.  As soon as the Renew Gold came in, I picked up a bag and gave the rest of this away.  It’s very similar to Renew Gold in that it’s a rice bran and flax product, with high amounts of fat, but it doesn’t have copra, and the NSC is 1% higher at 18%.  I don’t know why he did so much worse on this, and why he does so well on the Renew Gold. 
  • (Edit to add: I believe soy is the issue I’ve been having with many bagged feeds; and I’m guessing that binders are the reason grass pellets/cubes don’t work?)
  • Beet Pulp – beet pulp is a great base for a PSSM diet if your horse can handle it! I had to take Jax off beet pulp within about a month of starting it for the first time.  He started head shaking and having exercise intolerance issues.  I couldn’t source unmolassed beet pulp so was using the soak, rinse, repeat strategy until the water ran clear, so it’s possible that the molasses caused the issue.  Molasses is high potassium, which causes issues for Jax, so whether it was sugar or potassium, I’m not sure. Update January 2021: Jax has been on Standlee beet pulp pellets for about 6 months, and doing amazing.  I’m now wondering if the Copra that I mixed into the BP the first time was the issue.  Looking back it’s possible the molasses from BP and the copra together could really upset his balance, as copra is over 2% potassium (so ver high!)…

Past PSSM Horse Supplements:

  • AlCar or Acetyl L-Carnitine – used as an alternative to the higher fat Type 1 PSSM diet.  Jax did well on this for a couple of months, but when the weather turned cold it didn’t seem to help and I took him off for a while.  When trying to add it back into his diet, he became spooky and not quite right, so I took him off and started adding fat instead.  Carnitine is a derivative of Lysine and Methionine, 2 of the 3 limiting amino acids that are supplemented for PSSM2 horses.  So if Lysine and Methionine are fed in high enough amounts, the body should produce it’s own carnitine.  The body can also alter Carnitine to Acetyl L-Carnitine and vice versa through normal functions, so assuming the horse’s system is functioning properly, and Lysine/Methionine are in high enough numbers, Carnitine/AlCar should not need to be supplemented.  That said, some owners of both PSSM 1 and 2 horses report that AlCar helps (even with protein/amino supplementation), and apparently it also helps IR horses.
  • Tie-By –  contains Vitamin E, L-Carnitine (not AlCar), chromium, and other ingredients to help tying up.  I tried this before I knew he was PSSM1 positive, as I suspected he could have a muscle issue.  It seemed to help.  After diagnosis I took him off after hearing that chromium may negatively impact PSSM1 horses.  However, I’ve since read that both Dr. Valburg and Dr. Valentine have stated that the amount of chromium in many of these products shouldn’t be a problem, though I can’t find a direct quote from either of them. (edit to add: Jax went on AZ Copper Complete in late 2018, which has chromium, and is doing really well on it!)
  • Uckele Sport Horse Grass – I was really looking forward to this supplement when we started it, but he never did real well on it.  It was subtle, but there was a problem.  I suspect it was the gram of potassium, but he also has issues with sulfates and possibly soybean oil, so that could have added to the issue.  I removed it when they stopped making the powder version, and he immediately improved.
  • Uckele U-Balance Foundation – I really liked this supplement, and Jax did well on it (after initially snobbing it pretty hard – I had to work him up to 1/2 dose over about a month’s time).  I stopped using it because it apparently tasted really bad, and I had to grind it in my blender to get him to eat it (it’s pelleted, couldn’t find a powdered version).  I believe the copper is the taste issue, as he doesn’t like the Uckele copper that I’ve since used (though he does eat enough to get results, he still won’t eat a full dose).  However my guy also seems a bit off when on copper/zinc polysaccharide, so it may have been that. Foundation is a really nice supplement if your horse will eat it.

5 thoughts on “PSSM Diet – An Individual, Research Backed Case Study on Feed Regimens, Feed Triggers, and More!

    1. St. John’s Wort is like many other herbs – it’s toxic in too high amounts. Small human doses won’t hurt a horse. Being natural, herbs have a reputation for being mild and, often, having no effect – but they are like medicine – you don’t overdose on medication, and you don’t overdose on herbs. Growing wild in the field is dangerous, but small doses used with intention (and knowledge) can be helpful.

  1. Hi Jen, I want to try the chelated calcium. Can you give me an idea of what amount to start with? Short version of a long story: I have a biopsy confirmed pssm2 PRE mare. She is like Jekyll and Hyde – maneageable from late June – Dec when things slowly decline to unrideable by mid March. Spooking at every silly thing, hypereactive, extreme body tension. No amount of work makes it better. She is out on grass with a muzzle as soon as it drys enough each May. The grass runs out in Oct and no grass from Dec til may ish. Gets very boring 1st cutting, adm mineral supplement, mag oxide 25g, and whey protein. Mixed into a cup triple crown a cup triple crown senior, twice per day. Started whey about 5 mos ago, that seemed to be a game changer and improve things tremendously, extending our work season til now (previously things began going off the rails in Jan). Any amount of second cut hay (alfalfa/clover/orchard) makes her nuts. In the past tried her on high protein ration balancer- nuts (soy). This has been going on consistently for 4 years. Improving with grass. Why? Don’t know. I’m in Ohio btw – so definite seasonal changes. Have another biopsied pssm2 mare in barn – similar story. Have suspected low calcium, finally had bloodwork done that included ionized calcium, line was nearly indistinguishable from low side (tho vet called it normal). PTH was nearly indistinguishable from high line. Hears the thing tho, had a similar story for another pre mare (distantly related, not tested) paid for the equine cheated calcium supplement (not cheap) – she got worse on it. So I’m not willing to spend $100 to try with current horse. But I see the linked Ca gluconate is reasonable. So maybe worth a try, I just don’t k know how much.

    1. This mix provides less than half of the chelated calcium per scoop of Lam Essentials in the amounts I usually give (I typically feed 1 tsp – I think Lam Essentials has 3-4 grams per serving?). That amount is a little light during certain seasons, so I sometimes raise to 2 tsp depending on what the horses seem to need, but you can go higher if needed! I feel like Jax did well starting on the higher amounts in Lam Essentials and am unsure if he’d have reacted so quickly to the amounts he gets now, but a smaller (800 lbs compared to Jax’s 1250 lbs) horse did great starting on these amounts and rarely needs more. This horse is neurological rather than PSSM, and didn’t respond to EquiFeast but immediately responded to this mix (he wasn’t put on Lam Essentials though since he’s not PSSM, which could be why it didn’t work as he 100% acts/responds like a PSSM horse).

      If you don’t want to do the mix but try just chelated calcium, a little over half of the mix is calcium gluconate, so I typically feed a little over .5 tsp, or a bit over 1,200mg (1.2g) of calcium gluconate per day, up to 2,400mg/2.4g if I feed 2 tsp of mix. I no longer feed any magnesium on a daily basis, and I’m not sure I like mag oxide even though I used it for years (he started getting over-reactive on it after I tried higher dosing like Rockley Farms suggests). I do feed a small amount of magnesium gluconate on occasion (1.2g max) or ImmuBiome Focus which has .5g per serving. I did this just a few days ago as everyone was getting wound up with weather changes and grass spikes, and it calmed them down really quick. That said, mine have been on chelated calcium for well over a year now, I suspect when starting with chelated calcium you’d want no added magnesium to ensure the chelated calcium can have full effect as soon as possible.

      I hope this helps!

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