Myth Busting - Horses and Daily Salt Requirements

Horses need salt - and they know it! Forage diets are a poor source of salt, so supplying loose salt in daily feeds is recommended for all horses. Horses need salt to get the essential electrolytes sodium and chloride which support nerve and muscle function, hydration, and stimulate thirst. Horses will seek out salt, and if it's available they will normally consume what they need to meet their nutritional needs and no more. 

Myth: a 500kg horse needs 25 grams of salt a day

Fact: The amount of salt a 500kg horse needs each day varies depending on the heat, the level of exercise they do, and even what enrichment they have in their environment.

The 6th Revised Edition (2007) of the Nutrient Requirements of Horses by the National Research Council (NRC) recommends at least 25 grams of salt per day for a 500kg horse that is not in work, on a cool day. So that gives you a good idea of an absolute minimum salt intake level.

Myth: my horse needs the same amount of salt every day

Exercise, higher environmental heat and humidity can all increase your horse's sweating and salt losses. Researchers have determined that horses in high levels of exercise may need up to 200 grams per day!

Even when they are just trotting and cantering in moderate temperatures, horses can lose 0.5 - 1% of their body weight per hour - that's 5-7 litres of sweat per hour - and they will lose more in high heats, or during extreme exertion.

Did you know: In a 100 mile competition an endurance horse could lose 25 litres of sweat!

That's a lot of salt lost in sweat, and that amount should be replaced with an electrolyte product as well as supplying their daily maintenance amount of salt.

Myth: My horse only needs salt not electrolytes

Fact: For horses exercising regularly or in heat and sweating often, the NRC recommends that the salt in your horse's feed should be augmented with electrolyte supplements as well to replace large losses of sodium, chloride, and potassium in sweat. Just check the level of salt in your electrolyte and count that as part of your horse's dose - some electrolytes are around 80% sodium chloride (table salt) already.

Myth: Too much salt is toxic for horses

Fact: The NRC advises that as long as horses have constant access to fresh water, they can tolerate up to 6% of their total feed intake as salt, and excess sodium and chloride will just be excreted. Salt toxicosis (excessive sodium in the blood) is rare. Salt deficiency (which can cause fatigue, muscle weakness, decreased appetite and 'pica', horses to start eating dirt or licking things) is more common than salt toxicity.

However, feeding very high levels of salt may aggravate ulcers or possibly contribute to their formation, and it may alter the horses gut microbiome by killing certain organisms, so to avoid these consequences it is worth not overdoing it.

Myth: horses should only have free-choice salt 

Facts: In a 2025 scientific study on stabled and/or penned horses, researchers observed that although each horse consumed different amounts of salt daily, and none met their recommended daily salt intake level through free choice salt, it didn't make any difference to how much salt each horse chose to eat if the salt was loose salt or a salt lick block. A larger study by Kentucky Equine Research including horses in pasture as well as stabled showed that the horses did consume more of the loose lick salt than if they had a salt block.

The key take away is that your horse will most likely not meet their all their salt needs through either form of free-choice salt.

Myth: all salt is created equal

Fact: Plain salt is great for horses.

Studies have shown that Himalayan pink salt can contain high levels of lead and arsenic, sometimes exceeding safety standards - one study indicated lead levels 130 times higher than in white table salt. It's best to only buy from reliable brands.

If you use iodised salt, check your supplements for iodine and make sure you aren't feeding too much, as this can cause goiter, a rough coat, lethargy - and more serious consequences.

Salt licks are normally 'trace mineralised salt' meaning that minerals have been added. When horses are fed fortified feeds (containing minerals and vitamins) and have access to a trace-mineralized salt block which they eat to get the salt they need, they may end up getting too much of some nutrients, for example copper, zinc, and manganese.

Myth: horses don't need salt in winter

Fact: Salt should be fed year-round, as it stimulates the thirst mechanism and helps horses drink enough water even when it's cold, keeping them hydrated and helping to prevent impaction colic in winter.

Myth: our horses diet doesn't already contain salt

Fact: Many equine supplements and horse feeds contain some salt. Even pre-packaged chaff can contain salt. Check your horse's feeds and supplements to see what their sodium levels are. Even pasture grass contains a (usually tiny) amount of salt.

Shop Salts & Electrolytes for Horses.