Why I Wouldn’t Give My Horse Gatorade

The Science · The Library  ·  By Sara Kirkwood, Founder of Improve Equine  ·  September 2026

If you’re going to give your horse Gatorade, at least let’s update the information you have about it — and make sure you know there are better alternatives.

So, there’s a very popular video going around right now of a person pouring Gatorade into their horse’s water bucket. I don’t normally do this, but if you’re going to give your horse Gatorade, at least let’s update the information that you have about it and make sure you understand that there are better alternatives.

If you’ve used Gatorade, I get it

If you’ve used Gatorade because it was an emergency — you needed your horse to drink, and it’s at every gas station and convenience store — I get it. You got what was available and made it work. That’s usually when vets recommend it.

If you’ve bought it in bulk to hydrate your horse and replace salt and electrolytes, you’ve already shown me something: you prioritize hydration and you plan ahead.

So let’s make that hydration strategy even better.

Here are the reasons why I wouldn’t give my horse Gatorade — or any sports drink made for people.

One: It isn’t replacing their electrolytes

I wouldn’t give my horses Gatorade if I thought I was actually giving them meaningful electrolytes. Gatorade, like every sports drink, is formulated for humans. Human sweat is hypotonic, meaning that we don’t sweat out as much salt when we actually sweat. Horse sweat is hypertonic. They sweat a ton of salt.

McConaghy and colleagues (1995) collected sweat from horses in training and found a horse’s sweat is saltier than the their own blood; and it got saltier the longer the horse kept sweating. Then McCutcheon and Geor (1996) measured how much that actually adds up to. Thoroughbreds working through a simulated three-day-event speed and endurance test in hot, dry conditions lost about 19 liters of sweat and roughly 200 grams of electrolytes. That’s more sodium, potassium, and chloride than they took in from their daily diet.

So I did a little eye-opening math. A 20-ounce Gatorade has 270 milligrams of sodium and 80 of potassium. In the McCutcheon and Geor study, two hours of training in cool, dry weather cost those horses about 43.5 grams of electrolytes. That’s roughly 57 bottles of Gatorade to replace it. Two hours of training in hot, humid weather? About 150 bottles. The eventing test in the heat? AROUND 260 BOTTLES OF GATORADE.

When you are giving a horse a sports drink that is designed for a human, it is slightly salty water that you then pour in a bucket of water and further dilute. It’s not helping your horse restore their electrolyte balance.

Two: It’s not cheaper

People seem to think that Gatorade and other sports drinks are the least expensive way to get hydration into your horses. Not true. A 32 ounce bottle of Gatorade is between $1.78 and $3, depending on where you buy it. If you look at products that are designed for horses — both those with electrolytes and salt in them and those without — they’re averaging a couple bucks per serving, if not lower. Mine, in bulk, is 95 cents or less a serving.

Three: Sweeteners

Owners are much more educated on sugars in their horse’s diet… and some people say it’s not that much sugar to give their horses… but some horses can’t tolerate it.

With that awareness, people are often pivoting over to something sugar-free, which can carry new concerns. Gatorade Zero is sweetened with sucralose and acesulfame potassium. Sugar-free sports drinks in general use sweeteners that are now coming out, at least in human studies, as negatively impacting gut flora.

In a 2022 randomized controlled trial published in Cell, researchers gave 120 healthy adults saccharin, sucralose, aspartame, or stevia for two weeks — all at doses below the acceptable daily intake. Every one of them changed the gut microbiome. And when the researchers transferred those people’s gut bacteria into mice, the mice showed the same effects. Sucralose is one of the two sweeteners in Gatorade Zero. That’s human research, not horse research.

These are hindgut fermenters. We spend a ton of money on probiotics and prebiotics to try and make sure their gut flora stays healthy. If you give them an artificial sweetener, you’re potentially damaging that flora that you just spent a lot of money to build up.

So, what would I give my horses instead?

Well, the first is, I separate salt and electrolytes.

Studies have shown that horses actually tolerate salt and electrolytes in their feed better than they do if they are dosed by syringe or by water. That’s because the feed buffers the stomach — it’s not landing on an empty stomach.

When Holbrook and colleagues (2005) gave horses concentrated electrolyte paste by syringe once an hour for eight hours — the way it’s commonly done at endurance rides — those horses developed significantly more, and more severe, gastric ulcers. But when Alshut and colleagues (2023) fed salt pellets with meals twice a day, it neither caused nor worsened lesions.

And it’s not just that feed doesn’t cause or worsen ulcers. Putting it in feed is also a more accurate way to dose. Even with a salt and electrolyte hydration beverage designed for horses, I don’t know how much my horse is actually getting — it depends on how much they drink. So I put it in feed. That way I know exactly how much my horse is getting.

Salt is also incredibly cheap, and in this economy, I have to be financially savvy. I put two to four tablespoons of plain salt, depending on the conditions, into my horse’s feed every day. If your horse won’t eat granules, you can use the pelleted form. A lot of horses do better with that.

The second is electrolytes. In low activity, temperate climates, your horse’s electrolytes are taken care of by the feed that they get — meaning the hay, ration balancer, or grain that is fed at the recommended rate. A properly balanced diet is already giving them their electrolytes.

Now, if you add on top of that heat and/or exercise, then the electrolyte profile is going to be unique for what your conditions and activities. A horse that’s standing idle and sweating in a pasture is going to need a different electrolyte profile replaced than a horse that’s doing a 50-mile Tevis race, or a horse that’s doing a two-minute Thoroughbred race, or a barrel race, or a three-day event. You get the picture.

If you decouple your salt and electrolytes from your hydration, you can optimize and tune for both.

Then we can focus just on hydration

Personally, I’ve developed 12 different flavors that are whole foods, herbs, and spices, with no added sugar, based on flavors horses have been shown to prefer. When horses have access to a drink they find desirable, they voluntarily drink more.

Because we are not trying to mask any salts or electrolytes, the dose is also very small, so it’s not a significant amount of calories.

Now if you choose to give your horses Gatorade or any other sports drink, you have the information. You are paying the same or more for sweetened water that is not going to move the needle on your horse’s electrolytes or salt.

References

• Alshut, M., Bachmann, M., Venner, M., et al. (2023). The effects of feeding sodium chloride pellets on the gastric mucosa, acid-base, and mineral status in exercising horses. Journal of Veterinary Internal Medicine.
• Holbrook, T.C., Simmons, R.D., Payton, M.E., & MacAllister, C.G. (2005). Effect of repeated oral administration of hypertonic electrolyte solution on equine gastric mucosa. Equine Veterinary Journal, 37(6): 501–504.
• McConaghy, F.F., Hodgson, D.R., Evans, D.L., & Rose, R.J. (1995). Equine sweat composition: effects of adrenaline infusion, exercise and training. Equine Veterinary Journal Supplement, 20: 158–164.
• McCutcheon, L.J., & Geor, R.J. (1996). Sweat fluid and ion losses in horses during training and competition in cool vs. hot ambient conditions: implications for ion supplementation. Equine Veterinary Journal Supplement, 22: 54–62.
• Suez, J., Cohen, Y., Valdés-Mas, R., et al. (2022). Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell, 185(18): 3307–3328.
• Van Diest, T., Kogan, C., & Kopper, J. (2021). The Effect of Water Flavor on Voluntary Water Intake in Hospitalized Horses. Journal of Equine Veterinary Science.