Welllllll, the answer is "yes, I guess not"
Yes, there quite a few high quality and ethical IR supplements out there. Do they all work equally, or even at all? No
And that is because IR, EMS, and, even Cushings horses to a degree, are dealing with an issue that involves their metabolisms ---- which functions differently in every horse, just like with people.
I say Cushings to a degree because cushings is largely a pituitary gland issue (PPID) but the metabolism does manage to get involved and Cushings horses can also be IR or EMS
I had both my IR and EMS horses on Magnesium Oxide until a few months ago. The EMS horse for 5 years, the IR horse for 2 years (those times being when they were formally diagnosed).
I took them both off the Mag Ox and chromium and there's no difference whatsoever; actually the EMS horse is doing better and his blood tests show that to be true
Herbs can play a huge part in the success of some horses yet not make a pinch of salt in lowering the insulin of the next one.
My 25 yr old EMS horse is on Chastetree, it does wonders for him but doesn't do a thing for the IR horse.
I switched the IR horse to Chia seeds and even the vet asked what I was doing different because he's lost weight and his hooves are staying cool----so far.
I wouldn't swear to it but I'd probably, literally, kill the 25 yr old EMS horse if I fed him chia seeds.
There are manufactured products that folks swear by - Remission quikcly comes to mind.
They are allowed out to pasture (22 acres) 8 - 10 hours every day. We have a lot of steep hills, they traverse most of that pasture, so they get a lot of exercise.
The EMS horse needs a grazing muzzle only in the Spring, the IR horse is going to be stuck in one either until the world ends on December 22nd because that's when the Mayan Calendar runs out or, the temps are cold enough to freeze his breath to the muzzle
What both of my metabolic horses have in common is they eat soy-free and nothing with grain in it
. They both eat a mix of quality orchard grass hay and bermuda grass hay.
Dealing with metabolic issues is literally living in a state of confusion for the rest of the horse's life. I have had to adjust their diets at least once a year. That generally happens right when I think I can breath a sigh of relief and something within one of them changes
I said all that to say: In the end, the first go-to is Magnesium Oxide but make sure the only thing it might be mixed with is Chromium. If there are fillers, the product has less chance of being successful.
You can always go to Dr. Kellon's website and do some reading. I think she also has links to other credible/informative sites. Equine Cushing's and Insulin Resistance Information
I haven't read this site in a very long time but she used to be pretty far Right on her thinking. I am a lot more liberal and so far it is working for me.
My 25 yr old is 5 years into living with EMS and the 17 yr old two years with IR. I really won't know how successful I have been, modifying things I should be doing, until it's time to send them on.
Believe me, I get a lot of forum flack (not on this forum) for how I manage these two but next to me, my vet knows them best and his words are "it's working, so keep doing what you're doing". I think his silent parenthetical clause is "just don't tell me anything"
I'm not sure how much help I've been