Feeding Salt To Horses

(This blog’s header photo is of a white salt block in a stall.)

When we see a salt shaker near our food, many of us grab it and shake it all over our plate.  The tiny white crystals scatter off the plate, continue to bounce chaotically across the table and plunge off the edge disappearing on the floor below.  We don’t for a nanosecond regret the loss of these lost particles.  It’s the cost of doing dining business as long as the enhanced taste of the extra salty food hits our tongue so we can close our eyes and savor the moment we have been dreaming all the long, hot afternoon.

We stuff in more of this tasteful salt covered food not wanting to even talk.  We chew then we stuff more salted chips or fries or meat into our mouth.  After minutes pass something inside our brain says to drink.  The cold beer or soda is the icing on this moment of culinary delight.  All the Covid and political problems vanish as we let out a small burp of delight.

Then a thought comes to us.  Did we hear or read something about eating excess salt and that it causes heart problems?  We ponder and look at others around us.  They don’t look like they are having a heart attack.  You eat more food even adding some more salt by dipping the potatoes into some lone salt crystals you see on your plate.  In a minute you again feel thirsty so you reach for your glass.

Unknown to you is that you have started a destructive inflammatory process discovered in humans and in multiple lab animals big enough to get one of the largest pharmaceutical companies in the world to make a drug to stop it.  There is a good possibility this process also occurs in horses and if you are adding granular salt to their food, you may be adding to their metabolic issues including insulin resistance and laminitis.

What Is Salt?

The salt we add to food is the bonding of 2 elements: sodium (Na) and chloride (Cl).  When they become “charged” they attract each other.  In the charged state they are called “electrolytes” and are written this way: Na+ and Cl- When bound together they share and cancel their + and – charge to become neutral or stable as NaCl.  This is what we shake on our food or add to the food of horses.

Na and Cl are in every cell and are required for life to exist.  It is very soluble in water as every cook knows.  It is in the blood and tears of us and our horses. When replacing tears or adding hydration to blood, physiologic saline is used – salted water – at a concentration of 0.9%.  This means basically a pinch of salt in a liter (about a quart) of water.

Salt is lost when we lose any fluid, especially sweat.  A complex hormone system works hard to maintain our salt levels but we are only made aware of any imbalance when this system makes a request to our conscious brain.  If the salt levels rise (dehydration) we get thirsty and when salt levels get low (over hydration) we seek salty foods.

Balancing salt is very easy but has problems in extremes.  For example pigs can die from “water toxicity” when they are first severely dehydrated and then rapidly rehydrated with water.  The best and, in my opinion, only way to keep salt balanced in horses is to have water available at all times and make solid mined salt blocks available for them to lick if they want to.

Let me explain why I think adding free salt to horses in their rations is a bad idea.  First it is bypassing the self regulation process forcing salt intake when it is most likely unnecessary.  Second, if horses are like other mammals tested, adding salt to a dehydrated horse will cause inflammation to the kidneys leading to a transitory rise in blood pressure (bad idea for horses with laminitis) and it will also inflame the islet cells of the pancreas producing more insulin (bad idea for insulin resistant horses).

How does adding Salt To Food Cause Inflammation?

The information here is for humans as well as lab animals that have also been tested.  No work has been done in horses but it would be interesting to get some normal values for uric acid as well as blood pressure as these are not routinely tested at a farm.

There will be a bit of science here.  Please remember that I usually can make the complex easy to understand so give this information a chance.  It is now known in all animals tested (this includes humans) that when excess glucose is eaten it can be converted into another sugar called fructose.  This is HUGE so let me explain.

Starch (which is grain and hay), when fed EVERY DAY in excess of caloric needs, will be converted into fructose with the sole purpose of adding body fat for the upcoming winter.  Grasses that are freeze resistant as well as wheat, barley and rye have a higher level of fructose already in the plant in the form of fructans.  Glucose has the bad reputation but in reality, it is fructose that will eventually cause the problems.

The enzyme that converts glucose into fructose is called aldose reductase and this is where the pharmaceutical company is attacking the problem.  They have created a drug that will inactivate this enzyme. An enzyme makes a chemical reaction possible and without it, the process stops.

Within the engine of every cell (the mitochondria), a fuel is added to create energy.  It is like gas going into your car’s engine, being burned in an explosion, that gives the power to move your car.  The most common fuel in you and your horse is glucose.  In the mitochondria, a molecule called ATP is changed to ADP and then to AMP and these 2 conversions create the sparks of the energy needed to operate the functions of the cell.  Then the AMP is converted back into ATP for another cycle of the engine.  In this reaction, only about 10% of the ATP is used before the cell slows down the reaction to preserve this important molecule.

Fructose can also be used as a fuel in the mitochondria also converting ATP to ADP to AMP.  Energy is made but the recycling of AMP back to ATP is not done.  In fact the regulation to preserve the ATP is also reduced consuming about 40 to 50% of the ATP leading to exhaustion of the cell’s mitochondria.  What happens to the left over AMP?  It becomes uric acid (UA).  This stuff is really interesting.

UA in men is known to cause gout because all purines cause gout and UA is one of the best.  What researchers also found out is that UA inflames the kidneys.  This is the direct cause of hypertension (high blood pressure) in humans and lab animals.  In experiments, removing fructose by blocking the enzyme aldose reductase reversed hypertension and secondary heart disease.  Completely reversed it!  If hypertension is created, could this be associated in some way with inflammation in horse’s hooves (laminitis)?  It certainly wouldn’t help it.  But there is more…

UA also inflames the islet cells of the pancreas where insulin is made.  They found in humans and lab animals fed excess glucose daily created more fructose which led to all having metabolic syndrome.  This included high blood triglycerides, obesity, fatty liver, insulin resistance and diabetes.  But when aldose reductase was blocked, the indicators of metabolic syndrome that I mentioned completely normalized!  Obese humans and lab animals became thin with all parameters normalized.

Now you can see the value of creating a drug that blocks the enzyme – but wouldn’t it be better to eliminate sugar from the daily diet?  But that isn’t the question for this blog.  Why I am talking about the conversion of glucose to fructose in a blog about salt?  I thought you’d never ask.

Salt Plus Dehydration Activates Aldose Reductase

Past research has shown that a low salt diet was “heart healthy.”  It turns out that for some unknown reason, when salt is eaten WHEN THE BODY IS DEHYDRATED, the higher saturation of salt in the blood triggers aldose reductase to convert glucose into fructose!  If you drink the beer / soda / water BEFORE eating the salted food, the enzyme is not activated and uric acid is not created.  But as soon as you become thirsty, the enzyme is already at work.

No one knows exactly why this salt / hydration triggers the enzyme but it is clear that it does.  Because of this, I always drink some water before a meal.  But does your horse?  Is your horse hydrated before you feed a meal with added salt?  While we have no one looking for this enzyme in horses and no one is measuring UA, blood pressure or any other parameter, I feel better just assuming that I should NOT feed loose salt to horses.  Again, here are the reasons:

  1. Horses usually don’t need additional salt but if they do, they will self regulate it through licking it and drinking water when their body says.
  2. Adding salt to a dehydrated horse may have the same negative effects seen in humans and other mammals – Increased blood pressure, high blood triglycerides, fatty liver, insulin resistance, diabetes and obesity.