Decomplexicating Equine Nutrition Part 10 of 12 – Supplements

The nitty-gritty of nutrition seems to lie in supplements which include 1) the elements we call minerals, 2) the electrolytes we call salts, 3) the molecules we call vitamins and 4) the herbs. I hear a lot of people proclaim that paying attention to and supplementing for the lack of these things will enhance the health of the horse measurably. One example of this is the addition of magnesium to help calm the horse.

I have said this several times in these blogs on nutrition and it’s worth repeating here. It is NOT the addition of things that makes the horse healthier. It is the removal of things harming the gut microbes that will turn the health of your horse around. Before we go further, let me introduce you to what these things are.


Vitamins are organic (containing carbon) compounds occurring naturally in the foods eaten and several are required to prevent disease in humans. However, in the horse, very few vitamins are required due to their very different diet and digestive system. Deficiencies have occurred in some vitamins but only in horses that are starved or have been fed poor-quality pasture and hay. This includes hay that is over a year old. In other words, if a horse is outside eating good pasture during the growing season and is fed hay during the dormant winter season then there are no known vitamin deficiencies in horses according to extensive research done in the field of equine nutrition.

Yup! All those vitamins you are feeding are not necessary as long as your horse is not experiencing starvation.

The elements that make up all vitamins are the same as proteins: Carbon, Hydrogen, Oxygen and Nitrogen. A few have Phosphorus or Sulfur and one has Cobalt. All of these elements can be found in the foods the horse eats and thanks to the bacteria in the gut and the functioning liver, it is unlikely that horses suffer from vitamin deficiencies unless they are starved.

Vitamin A – Deficiencies have been reported during severe droughts over a long period of time. It is derived from carotene found in plants. Carotene in stored hay will diminish over time. Deficiencies include loss of appetite, night blindness, excessive tearing, thickened corneas and skin, reproductive problems, respiratory problems, seizures, blindness, bone disease and decreased disease resistance. Chronic (3 to 4 months) over-supplementation can cause depression, unthriftiness and death. Prevention is good pasture and hay.

Vitamin D – deficiency is unlikely when fed sun-cured hay or they have adequate exposure to sunlight during most of the year. This vitamin is now considered a hormone because of its many functions including the modulation of an over-responsive immune system.  Deficiency causes loss of appetite and weight loss when deprived for about half a year. Over-supplementation with Vitamin D in horses has been shown to cause several system dysfunctions (bones, kidneys) that can lead to death in 3 to 4 months. In humans, most are low in Vitamin D and it has been shown that those with D3 levels above 40 ng/ml resist viral infections such as COVID-19.

Vitamin E – There are no known deficiencies; however in young horses a lack of Vitamin E helps with red blood cell stability. There is some evidence that Vitamin E combined with Selenium may prevent white muscle disease but other factors may be involved.

Vitamin K – This is not necessary for horses as it is produced by gut microbes. Vitamin K given at the manufacturer’s recommended dose caused kidney damage in one study with bloody urine formation.

Vitamin B – Additional B vitamins are not needed in the horse due to sufficient amounts in good quality hay and the production of B vitamins by the gut microbes in the hindgut. However, in horses with colon damage (ulcers) or that are stressed, these microbes may not produce enough B vitamins.

B-1 (thiamine) deficiency may occur in horses fed poor quality forage, bracken fern or mare’s tail.
B-2 (riboflavin) deficiencies have not been reported in horses. The one disease associated with a deficiency in the past has now been attributed to another reason.
B-3 (niacin) deficiencies have not been reported in horses.
B-5 (pantothenic acid) deficiencies have not been reported in horses
B-7 (biotin) deficiencies have been shown to cause defects in the surface of hooves in pigs but no requirement has been made for horses.
B-9 (folic acid) low blood levels can occur in horses without pasture but no known diseases.
B-12 (cyanocobalamin) deficiencies have not been produced experimentally in horses

Vitamin C – is not a requirement in horses as they produce enough vitamin C in the liver.


Minerals are elements (see the periodic table of elements, also known as atoms) required by horses to perform necessary functions in the body. For example, iron is needed to attach oxygen to the hemoglobin protein within the red blood cell. Minerals cannot be made by the horse and therefore they are considered essential for life and are consumed in the food they eat. The 5 major minerals in humans are calcium, phosphorus, potassium, sodium and magnesium. The remaining minerals are called trace elements and include sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine and selenium.

Calcium (Ca) and phosphorus (P) are essential in bone formation, especially in young growing horses. While a deficiency in calcium is almost impossible except in extreme cases, phosphorus deficiency can cause a series of problems. Remember ATP in the mitochondria? The “P” in ATP is phosphorus. On the flip side, too much phosphorus actually prevents the absorption of calcium and will cause soft bones (rickets). This is why dicalcium phosphate is added to all grain mixes because all grains, especially wheat bran, are high in phosphorus. This was called “Miller’s Disease” a long time ago when horses were fed the byproducts of the milling industry. Today, wheat byproducts are still fed to horses but because dicalcium phosphate is also added, the disease called Nutritional Secondary Hyperparathyroidism (big head disease, brain disease, miller’s disease), a nutritionally caused calcium deficiency is avoided.

Magnesium (Mg) is often added by horse owners to calm their horses. A deficiency will cause hyper-irritability, tetany, glazed eyes and collapse so it makes sense to add magnesium to calm the excitable horse. However, the primary cause of magnesium deficiency is the blocked absorption of it caused by excessive feeding of calcium or phosphorus. So if horses are being fed excessive phosphorus from wheat bran and wheat middlings and then more calcium and phosphorus are being added in dicalcium phosphate to counter the high phosphorus, then it would be logical that the horse will become deficient in magnesium. Interesting… This would be an argument to avoid feeding grains with their high phosphorus content plus the added dicalcium phosphate rather than adding magnesium. Maybe this is the primary reason why removing grain from the diet causes horses to settle down quickly.

Potassium (K) – A deficiency in this element is not common in horses but an excess caused by a genetic mutation in Quarter Horses will produce muscle weakness called hyperkalemic periodic paralysis (HYPP).

Sodium (Na) and chloride (Cl) (salt – NaCl) – These elements are everywhere and are necessary for life in all systems within the horse’s body. This is why it is offered free choice to horses. I have rarely seen deficiencies but on occasion, I have seen a horse over-eat salt devouring a salt block in little time. This causes the horse to drink large amounts of water and urinate a flood of water. I call this kidney medullary washout requiring the normal kidney gradient to be re-established.

Iodine (I) – Too much or too little iodine in the diet will cause goiter, a term used to describe an enlarged thyroid gland. The third cause of goiter has an unknown cause (idiopathic). In all cases I have seen there is usually being fed a supplement with seaweed, specifically kelp which is high in iodine. Removing this supplement reduces the goiter to normal size. The horse shows no ill effects from a deficiency or an excess of iodine.

Iron (Fe) – The information about iron is extrapolated from humans and other animals and is presumed to be the same. Iron is conserved by the horse with very little loss with the exception of severe bleeding. This is called efficient conservation and because of this, iron is only absorbed when needed. A deficiency in iron is called anemia which leads to exercise intolerance. Excess iron supplementation (injected, fed or in the environment) can become lethal by replacing other minerals and causing tissue weakness (hemochromatosis, liver disease, diabetes). Older horses may have higher levels of iron due to the chronic storing of excess iron. There is a blood test to determine iron levels in the horse.

Copper (Cu) – Deficiencies are not common in horses. It may be part of the development of osteochondrosis in growing foals. Toxicity has not been established in horses.

Zinc (Zn) – Deficiencies are not common but toxicity has been reported in fields located near smelters of metals.

Manganese (Mn) – This is not an essential element but in one case where excessive limestone was added to a hay field, the hay then became low in manganese and the subsequent foals born from mothers eating this hay had severely deformed limbs. However, deficiency and toxicity are rarely found in horses fed good quality pasture and hay.

Selenium (Se) – This mineral is low in some soils and a deficiency can be seen in newborn foals as muscular dystrophy called “White Muscle Disease.” They are often too weak to stand or swallow and die of starvation. Testing and then supplementing the mare before birth will avoid this disease. Deficiencies in horses older than newborns horses have not been shown to cause problems though most commercial feeds add selenium routinely. Toxicity with selenium is more of a concern in the western states of America (Wyoming, Colorado, South and North Dakota, Montana, Utah and Nebraska) because some plants store selenium which is then eaten by the horse. Horse owners living in these areas are aware of this and avoid these plants. Toxicity causes “Blind Staggers” which may include lethargy, unsteady gait, difficulty breathing, diarrhea, increased pulse, respirations and temperature and death. While toxicity is not common in commercial feeds, it is a potential threat to all horses eating commercial mixes. With great sadness, my friend watched 12 polo ponies die a terrible death in front of him after all the horses had been given an IV medicine made with an accidental 10-fold amount of selenium. Care should be taken when feeding anything with selenium supplementation.


Electrolytes are elements that when added to a solvent like water, either lose or gain an electron becoming a charged ion. If a positively charged electrode is placed at one end of the water and a negatively charged electrode is placed at the other, an electric current is created by the charged ions moving through the water to either gain or lose an electron and become balanced (no charge). This is how the nerves, muscles and everything else works in all animals including your horse.

The common elements in horses that can become “charged” include sodium (Na+), chloride (Cl-), potassium (K+), calcium (Ca++), magnesium (Mg++), carbonate (HCO – – –) and phosphate (PO4 – –). The + and – signs after the elemental abbreviation mean that the element is in the charged or ionic state. Why is this important in horses? Because the only way to get these elements into a charged state is to keep them apart and separated. This is an activity in every cell in the body that expends energy on every moment of the life of the horse. It is just like two lovers each in separate rooms; there is great potential but a wall between them. When the potential between charged ions is signaled for and the charged ions come together, an action occurs through this created current by the movement of ions across the wall. Every action made in the body is because a potential between 2 charged ions created an electric current through an opening in the wall between them. Such actions include contracting a muscle, sending a nerve transmission, a heartbeat, a thought, the scratching of an itch – everything. These currents are what are measured in the EKG of your heart.

The charged elements are physically forced into the spaces outside the cell (extracellular space) or inside the cell (intracellular space). Na+ is primarily outside the cell and K+ is primarily inside the cell. Their concentrations are precisely controlled in the horse with the gradient between the two held constant. The same is true with all ions creating potentials across solid membranes. Whenever ions are allowed to come together, the potential is experienced, the current made and the action occurs.

The main causes of electrolyte loss in horses are extreme sweating and diarrhea. If your horse isn’t sweating (too cold, not exercising) or doesn’t have severe diarrhea, then there is no need to supplement with these elements because there are plenty of these elements in the food they eat. In addition, almost every electrolyte supplement for horses contains sugar in some form which is unnecessary to add to the diet.

Some signs of electrolyte deficiency in horses include muscle cramping (not exertion myopathy which is a genetic disorder), muscle exhaustion (calcium reserves are depleted) and synchronous diaphragmatic flutter (“Thumps” “Hiccups”).

HYPP is an electrolyte imbalance from a genetic mutation occurring in heavily muscled Quarter Horses within a family line. The potassium on the inside of the cell and the sodium on the outside of the cell is allowed to freely cross the muscle cell wall eliminating the potential to make a current and muscle contraction in a thoughtful manner.

Thumps occur in dehydrated horses when the potential between ions accidentally is triggered by the electric current of the heartbeat across the gap between the heart and the phrenic nerve lying across the heart on its way to the diaphragm. As the heart beats, the diaphragm contracts synchronously with the heartbeat creating a jerk of the diaphragm (a hiccup) ranging from mild to severe thumping. It is cured with rehydration using electrolyte solution IV.

Herbs and Spices

It has become popular to add herbs (plant leaves or flowering parts) and spices (plant seeds, berries, bark, roots, and fruits) to the diets of some horses usually for a specific benefit. In humans, they have shown a beneficial effect on the mitochondria of the cell. The part of these plants being attributed to these benefits is the polyphenols which are a group of plant chemicals that benefit cellular health and in particular, mitochondrial health. Coffee beans have the most polyphenols in human food but many other herbs and spices have them too including oregano, thyme, black pepper, turmeric, dark-colored berries and others.

There are no bad side effects of adding herbs or spices in moderation and in eastern (Chinese) medicine they are relied upon. Western medicine has not embraced these plant medicines as a form of therapy and I don’t think there are many good and reliable studies done on their use here. But let’s look at it another way. Would there be any need for herbal therapy if the horse has a healthy and non-inflamed gut? Ginger helps an upset stomach in humans but why is the stomach upset? Herb and spice plants are found growing in the wild, but not everywhere and not year-round. Could there be a lectin or carbohydrate conflict if used indiscriminately?

All herbs and spices are plants and therefore available to the horse if growing in their area. There are no known toxicities when eaten in the wild but some are toxic when given continuously and in excessive amounts for supplementation. The principles of feeding them are similar to all other plants – feed only when in season. Again, in a healthy horse with a normal gut microbiome, there is probably no need to supplement with herbs or spices unless guided by an experienced practitioner for medicinal purposes.


  1. Adding vitamins to the horse’s diet is unnecessary unless they are starving or on severely poor pasture and hay.
  2. Adding minerals beyond the requirements of the horse may cause health issues. Adding them to pregnant mares and newborn foals may be indicated depending on the environment where they live and the quality of forage available.
  3. Adding grain, especially wheat, with the addition of extra calcium and phosphorus may cause a magnesium deficiency with irritability as a result.
  4. Adding electrolytes is only necessary when the horse is or will become mildly to severely dehydrated through excessive sweating or diarrhea.
  5. Herbs and spices have a place when prescribed by a medical practitioner. However, in a horse with a normal gut microbiome and not starved, adding these may be unnecessary.
  6. Save money by not feeding extra vitamins, minerals, electrolytes or grain. Invest in feeding the best quality pasture and hay you can purchase.

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  1. Posting to my mustang page. New mustang owners are constantly asking what grains and supplements to give their mustangs. My advice: Besides grass hay, nothing. I can’t even put mine on irrigated pasture without consequences and they eat weeds better than my goats.

    1. Thanks Kerry for posting these to your Mustang page. These animals survive on the land which beautifully follows the annual intermittent fasting plan. Abundant locally grown grasses and plants during the summer followed by winter when there is little to graze on. This provides the basis for autophagy and hormesis causing renewed cell parts, stem cell stimulation, increased growth hormone, elimination of insulin and insulin growth factor, reduction of body fat and more benefits to health and vitality.

      In the human world where there is little pasture and abundant hay (last summer’s grass) and these forages are usually of one or two types of forage (monograms), adding a good protein source such as soybean meal will keep the hair coats and hooves in top condition.

    1. I want to address the feeding of a “mono-grass.” There is a risk to feeding only one type of grass and one type of hay. In the wild a horse gets a broad variety of plants each with characteristics that compliment the diet. In addition, this variety changes with the season. Allowing for a variety of gut microbes to thrive will give your horses the best advantage for thriving.

      For many horses feeding good grass hay is enough but adding a legume such as alfalfa gives a broader variety of amino acids. Adding soybean meal really supplies the needed essential amino acids. Remember that all vitamins are proteins so getting all the needed amino acids helps. Also remember that a normal gut microbe environment (the microbiome) will produce the vitamins. If there is in a disordered gut environment (dysbiosis) from constant feeding of sugar or the addition of stress (overcrowding, poor sleep environment, overwork, medications) then get this corrected first. The vitamins will follow.

      If using well water then a lot of the minerals are found there. Adding salt from a mined source adds more. Both macro and trace minerals are found in each as well as the forage you feed. If your horse is exercised in the heat and there is an abundant loss of sweat then maybe there is a need to add electrolytes. But electrolytes are only minerals that have lost or gained electrons so being sure there are enough minerals in the diet (water, mined salt) should preclude the need to add more electrolytes. Each case needs to be looked at individually but adding electrolytes in most horses is not necessary.

      Getting the gut microbiota right in every horse and then looking at each horse’s individual needs is required in good horse management. Adding supplements in the concern that you are missing something in the diet is taking the easy way out. Understanding nutrition from a science perspective allows for making better decisions and possibly “decomplexicating” your routine and saving some money while improving the health of your horses.

  2. What would you recommend for a competition horse that in the past has suffered from ulcers? Obviously a fiber based diet should eliminate them but I then worry about what to do hauling to and from shows. He refuses to eat hay while in the trailer…. very frustrating! In the past we’ve administered ulcergard a few days leading up to the event and then during. Would you continue this?

    1. A great question because of so many things! Thanks –

      The first thing to clear up is that you are talking about gastric (stomach) ulcers. An ulcer is a break in the mucous membrane (lining) anywhere from the lips to the anus. It is important to proceed the word ulcer with the location.

      All ulcers in humans are now associated with a gut microbiome dysbiosis meaning the normal amount and variety of the microbes in the affected section of the gut are not normal. In addition, in horses that are exercised or in this case trailered with an empty stomach will not have any material in the stomach to soak up the acid that is constantly produced in the horse. The empty stomach allows for the splashing of the acid onto the non-glandular portion of the stomach that can be damaged. This is what the vet looks for when scoping.

      A great fix for this is to feed a good amount of hay before shipping. This would work if the time in the trailer is only a few hours or less. Another option on a longer trip is to stop every few hours and feed some soaked hay cubes topped with something she likes such as a few carrot slices (not 3 whole carrots!). Maybe some Coolstance mixed with hay cubes / pellets plus water. Become her chef and experiment.

      Proton pump inhibitors in humans such as Prilosec and Peptide AC are now shown to alter the pH of the stomach which adversely affects the normal stomach bacteria (dysbiosis), diminishes protein digestion and shifts all the gut bacteria with a specific pH requirement up towards the stomach where they become ineffective. Most functional medical doctors are urging people not to use these proton pump inhibitors. Gastroguard and Ulcerguard are proton pump inhibitors and if used for a while may also contribute to the gut problems more than they alleviate the pain from the ulcers. It’s always best to prevent than to treat.

      However, the bottom line is to pay attention to your horse and to consult your vet if your horse is diagnosed with gastric ulcers. But as a preventive in a NORMA healthy horse, I would not recommend using a medication but would rather you try mor novel approaches.

      By the way, if you are still feeding anything other than pasture and hay then this could be the cause behind her not eating while traveling. She just doesn’t feel great. Some horse who refuse to load are actually pretty smart. Like someone who hates flying because they get nauseous, some horses say, “I ain’t goin in that thing cause I feel like crap every time my belly is shaken.” Once the gut inflammation is gone then all becomes good in the trailer. See the top video testimony of the woman at

      1. Thank you for your insight! Yep, it’s definitely gastric ulcers. I’ve tried various medicine and also herbal supplements over the years and have done many scopes so I have an idea of what does and does not work. Most is a waste of money! I have taken him off grain once before but I continued at the time to feed rice bran and beet pulp so looking back, I still didn’t commit 100% to the diet change. I’m currently on day 2 of your challenge and I have SBM and coolstance so it will be interesting to see the changes. Luckily he trailers and loads like a dream but just refuses to eat hay while in motion. We go to a show next weekend so I will be interested to see how it goes!

    2. There is a glitch with your comment and I know it has been approved but it keeps coming up unread. This is my attempt to correct this.

  3. What are your thoughts on sand colic? We live in sand. The recommendations have been to feed some type of product with psyllium fiber in it once a month to clear out the sand to prevent sand colic. I have used plain metamucil in the past but was told the amount I was feeding was not enough to do much good. I have fed Sand Clear before and will need to read the label to verify the ingredients. I have started the no grain diet and don’t want to add anything with sugar so I am wondering what your thoughts are on this subject. Thanks.

    1. Restoring the health to the gut by eliminating grain plus providing pasture and hay plus soy bean meal to restore the amino acids all will help move the sand out.

      You should test for sand in the feces. Unfortunately, most fell that a positive test (sand seen) means that the horse has a problem – which I agree with but it also means that it is coming out. I am more worried of a negative test because if there is sand in the gut it is not coming out.

      Maybe test for sand now and then weekly as the grain is eliminated and look for a pattern (none at first then some and then much later none would mean that peristalsis is now more effective since the gut inflammation is gone).

  4. Hello, Doc T. Thanks to all your blogs, I have been reading feed/supplement labels and looking up any words I don’t know. I have used Farriers Formula (cuz Thoroughbred feet) through the years. And found a new word they highlight. Phosphatidylcholine! Turns out SBM is high in this element.
    The main reason for this post, Farriers Formula is doing an independent research on Nutrition. They are wanting horse owners to send in blood samples for the research. if this link has issues. Just go to their website, click on research, it is the first on the list. I though you might be interested in knowing someone is looking into nutrition content in equine blood. As you have said, no one has done it in the past. But now, someone is at least attempting.

    1. Thanks for this Rebecca.

      Phosphatidylcholine Is found in soy beans but is removed in the oil extraction process when soy bean meal is made. This chemical is found in lots of food and is naturally occurring. The human can make some of it but most animals need to consume it. It is often called lecithin but lecithin is not pure Phosphatidylcholine. Choline is necessary in many functions such as making the neurotransmitter acetylcholine. Egg yolk and beef liver are good sources of this chemical. The bottom line is that Phosphatidylcholine is a natural chemical found in many foods but it is not often seen in horse feed. Good eyes!

      Life Data needs to be commended for their new world wide project. Blood samples are only collected from horses with specific illnesses including Cushing’s, insulin resistance and anhydrous is. This effort is long due because everyone speaks in generalizations about minerals in horses. While this project will take a year or longer, I will be excited to hear their results. If I have been correct, horses should self regulate their mineral absorption and should be able to make their vitamins. I know I set way outside the box on this but I have not seen vitamin or mineral deficiencies in horses (exception would be starved horses). My hypothesis is that the underlying factor for most diseases seen today is a lack of protein due to self consumption in horses eating carbohydrate laden meals daily. We all will see what happens and if they are successful, there will be a lot of changes in the nutrition and feed businesses. Thanks again!

      1. The first evening I found your website, I read until the wee hours of the next day. I remember you had a chart of the nutrients a horse needs and a comparison to what is actually in a bag of feed. I cannot find that page again. Where is it? Thanks

        Also, I ran across a person who has found that Andalusians seem to be low in Vit. E She has run blood tests on all of her PRE horses, and has a small community of Pre owners getting blood work done and finding the same problem. (posting results) Vit E testing below 400. What I don’t know is what is the proper amount a horse should test at? I can send info via PM in FB is you are interested, have questions, or want to follow the group, (because… curiosity)

        1. I think you are referring to the protein supplements available. It is here but you must log in (it’s free to sign up):

          The term “low” is relative. For Andalusians the Vit E levels may be low compared to the lab’s normal range but may be perfect for the breed. Who knows? For me it is important to look at the horse ands determine if there is anything wrong that can be attributed to a low level of Vit E. Then I would look for a root cause before I would supplement. In today’s world we seem to just test and add without understanding what or even if there is a problem.

          For example, decades ago the researchers were adding selenium to cattle to measure blood levels. They were surprised to see that the addition of oral selenium did not raise the blood levels. After some searching they discovered the treated water in the facility was binding to the selenium not allowing it to be absorbed.

          Another thing I did in practice was to inject Vit E and Se into mares before they delivered their foals to prevent retained placentas. While most horses tested were found to be low in Se, I found no correlation with Vit and Se levels with retained placentas. My injections did not seem to help even though back then it was recommended to boost Vit E and Se before delivery. In other words, who really knows what “normal” levels are and what are the consequences of an abnormal level? I believe there are too many other factors involved and at the root of most problems is inflammation, carbohydrate dependency with mitochondrial exhaustion, chronic protein deficiency and environmental stress. Let’s correct these and then determine what is “normal.”

          Thanks for letting me rant here ….. 🙂

  5. Thank you for your response – I always learn a lot from you. I am actually in between horse herds right now (my senior geldings passed on a couple of months ago and I’m almost ready to start my new herd) – I’m in the planning stages for feeding the new herd.

    Actually, most of the horse people I know around me have the same no pasture, no clean water, small space issues that I have. Horse property in the metro Phoenix area is very expensive and most people, including me, cannot afford 10 acres, nor 5 acres, not even 2.5 acres. Many horse people I know have less than an acre or board their horse who lives in a stall, isolated, fed twice a day and may be turned out for a couple of hours three times a week – thankfully, my horses have a lot better situation than they do. From time to time I toy with planting organic Bermuda grass in part of the horses’ habitat; may actually do that one day.

    I’m not keen on standard answers either and usually question them.

    My feeding regimen is always a work in process so it’s hard for me to compare to others. I’m not aware of mineral issues of anyone who feeds primarily grass hay, or for those who feed Purina Senior Feed and whatever joint supplement, colic prevention, vitamins, minerals, etc. their vet or Dynamite Specialty Company recommends. Most of us lay people wouldn’t recognize a mineral deficiency without a vet experienced in ways the deficiency(ies) would present itself. I so need to get back to your Horse Advocate nutrition program!

    When I was feeding minerals, it was Horse Tech’s Arizona Copper Complete ( – supposed to balance out the high iron and low copper issues here in the Southwest). The mineral block I last used was a Redmond Salt Block (no additives that I know of); the last loose salt I fed was Dynamite Natural Trace Mineral salt (no additives). I never fed electrolytes as I wouldn’t drink Gatorade myself. I learned the importance of protein when my seniors lost their topline (I looked but never found an amino acid supplement that was complete, so saved money there – I thought about adding SBM but my bias got in the way. I’ve now, based on your input, gotten over the bias). They had lost their molars a few years ago (years of vets power tooling them away before I learned the importance of a competent equine dentist) so feeding them enough to sustain them was a huge challenge. Had to resort to Nutrena Safe Choice Dry (minimal molasses) to keep them from looking like starved horses in addition to their many pounds of Standlee pellets three times a day.

    My new plan, based on my experience and your input: the new herd (younger horses) will get a variety of grass hays, some Alfalfa from time to time, non-GMO SBM (will add it to Standlee pellets so the horses will eat it), Redmond Salt Block (because I still have one — unless you think the Himalayan or sea salt is better). Will see how that goes. If I add anything it may be the Arizona Copper Complete (flax meal based – not sure if that will interfere with the SBM). I will definitely report back on how the new simplified (back to the original basics!) works out.

    P.S. If you know of any horses that need a great home (and within a day’s drive of Scottsdale, AZ), let me know! I’m partial to BLM mustangs, grade horses and minis. Pedigrees mean nothing to me, only the heart (good or hurt) of the horse is important. All my animals are/have been mutts. 🙂

  6. Thank you, thank you, thank you! I just stumbled upon your website today and have literally been reading the hours away! I have been struggling with a direction for my small breeding operation… long story short, and many attempted avenues, I actually began my grain-free quest back in October. I put everyone, weanlings/yearlings/broodmares/performance horses/pasture puffs on alfalfa pellets and a mineral. I have already seen my “higher than a kite yearling” turn into a calm, cool, collected citizen, so that alone makes me a believer! I’m so thankful I read everything when I did, as my 16 year old performance horse is starting to look a little “light through the top” as we get into the worst of our winter… I literally have a bag of oats in my truck that I was to start supplementing her with, but after reading what I have, I’ll be returning them! I was recently concerning myself with not providing enough amino acids to my growing horses, but I think what I read today brought me a little reassurance that I didn’t totally ruin my babies yet… however –

    I plan to do the official switch/addition to soybean meal after the winter passes, so I can actually see the results rather than 4″ of hair (yes, it actually was -55 with the wind here in WI today) and at that point I’ll be out of my current vit/mineral supply and not going back… that being said, with many-year-old hay (I do have a recent test, it’s still very respectable – however VERY high in calcium vs phosphorus…), coupled with the mares/babies, what mineral supplement would you add? I’m slightly obsessed with the “calculations”, however after reading what I have today, I’m attempting to tell myself to relax… maybe those numbers don’t HAVE to read 100%?

    I checked into Barn Bag and Farriers Formula, but due to the “numbers” still being low in phosphorus, copper, and zinc, I found I’m getting a better balance with MVP Mare Foal II – first number of ingredients: Soybean meal, alfalfa meal, corn distillers dried grains with solubles, L-lysine monohydrochloride, DL-methionine, calcium carbonate, monocalcium phosphate – do you think that level of corn distillers will be a problem? I would be feeding a 1400# mare 2oz/day. Also, at what age would you stop supplementing “weanlings”? 9mo? 12? With an older hay supply, would you suggest supplementing all? Also, when the young ones hit training/competing (barrel horses), would you just add additional alfalfa pellets for calories, or at any time would you look to oats again? Mineral at that point?

    Gosh, I could go on forever, so sorry about the novel and so many questions! If I may suggest, it would be fantastic if your site had a “FAQ” section.. I’m loving your answers throughout these comments!

    Thank you!!

    1. Why wait until spring to add soy bean meal? If your horse’s top lines are already affected then they are converting their own protein into fuel (glucose). They will need the amino acids provided by the SBM now. You don’t need to “see the results” because adding top line will take from 6 to 12 months to do. If the hoofs look bad then the results will be seen there in 2 to 4 months. And the hair coat should shed beautifully as the days get longer – with March 21st a target date for shedding (6 weeks away).

      I don’t add a mineral supplement for 3 main reasons. The first is that the best mineral supplement is the ground water they drink followed by salt with minerals. Second is the absorption of minerals is affected by gut inflammation and protein deficiency as well as the pH of the water. Without measuring the exact mineral content you really do not know the effectiveness of supplementing. Third, with the exception of starvation cases, I do not see mineral deficiencies in healthy horses. To my eye, the signs of protein deficiency is obvious but I do not see any mineral deficiencies. Adding SBM as a protein source provides a broad spectrum of absorbable amino acids which helps in the absorption and utilization of minerals.

      As a rule, if your horse is not sweating then they are not losing minerals as electrolytes. Iron in humans is highly regulated. The addition of dicalcium phosphate as a prevention of rickets in grain fed horses prevented the absorption of magnesium leading to hyper-excitability in most horses. Can the over supplementation of other minerals also have an adverse effect on the horse? I would rather let the horse find the minerals he needs in the water and food he consumes. The mantra here is to remove things from their diet, not add them except to help them survive in -55 degree weather. Hay is a supplement and so are blankets. Even a scoop of de-hulled (cleaned) oats won’t hurt for a bit until the temperatures get higher. But avoid “corn distillers dried grains and solubles.” This is inflammatory and is a by-product. Lysine and methionine are 2 of the 3 limiting amino acids and isn’t bad but is unnecessary when feeding SBM. Calcium carbonate is “Tums” and as an antacid is changing the pH of the stomach which may decrease the ability to break down proteins for absorption. It does help grain fed horses to feel better. The mono calcium phosphate usually is followed on the ingredient list with dicalcium phosphate. These ingredients prevent Ricketts caused by the high phosphorus of grains but also prevents the absorption of magnesium.

      Adding “calories” is a misconception. The energy produced from ketones derived from cellulose is more efficient at producing energy than energy derived from glucose in a starch meal (grain). In an ideal world, horses would only eat what they found in their travels. As grazers (technically speaking as opposed to browsers), the horse will get all the energy they need to perform with pasture, grass hay, a flake of alfalfa, 1 pound of SBM per day, salt and water. Supplementing is something horse owners do to avoid missing something and in doing this they really complicate things by dividing horses into age groups. Until I start seeing squirrels and other animals of the world eating different diets because of their age (for example senior squirrel feed or ration balancers), I would not recommend horses be fed anything but what they were designed to eat – ground plants. This is just marketing at its best which is geared towards people trying to do their best for their horses. Unfortunately there are too few horsemen old enough to remember what horses were like 50 or more years ago. They look great, had fewer illnesses and were fed less.

      To summarize – if it is extremely cold you must do what is necessary to help your horses survive. This includes extra hay and alfalfa (both equal in calorie production) and some cleaned oats (a source of sugar calories used to restore glycogen stores in the liver and muscles). Add SBM as soon as you can to restore any amino acid deficit. Have plenty of water available. Spring is coming and so is the pasture. Your goal right now is to eliminate gut inflammation and restore the amino acid reservoirs. The minerals will take care of themselves and if they don’t you can always add them once a deficit is discovered (but it won’t appear based on not seeing deficiencies reported in non-starved horses). See – I can write novels too. Doc T

      1. Hi Doc T, I have a question regarding your comments about why you don’t add minerals. I agree and 20 years ago my horses only got grass hay and think I had a salt block out for them. Very simple and they were healthy. But, they got older and so I started adding a whole bunch of expensive stuff to compensate for their age-related “deficiencies” and lack of quality forage. My horses are in the city, in the desert (Phoenix), on a dirt lot, no pasture, don’t have ground water to drink except when it rains hard and we have a small lake. I free-feed various hays (Bermuda, Timothy, Orchard, once in awhile a little Alfalfa) and am still trying to figure out how best to give them salt (loose plain OR loose mineralized OR plan/mineralized salt blocks – have tried all three ways over the years). Given that the nutritional content of cut & dried hay is not very high and they drink city water (we have a whole house water system so chlorine and other harmful chemicals are filtered out), are healthy horses still able to get/make all of the minerals they need? I think you are saying yes. The one thing I’ve not done is the SBM – I still haven’t gotten myself over my bias against soy, but may try it. If yes, my husband and our pocketbook will be ecstatic! Having gone through less is more to more is better and now back to less is more is liberating! Thanks!

        1. Thanks Lorraine. You have a special case in that you have limited pasture and “clean” water. Are there any horses in your area suffering from a mineral deficiency? Maybe ask your vet. I’m not interested in the standard answer I hear everywhere, “This area is low in selenium.” What I want to know (and would love to hear your findings here), are there any cases of mineral deficiencies in horses fed the same way you are feeding your horses in your area. Starvation cases should not be included.

          If you decide to add minerals please remember that many mineralized salt licks have corn syrup and molasses added. A pure salt such as Himalayan or sea salt may be good enough. Also remember that electrolytes are minerals with added or lost electrons and most electrolyte powders have sugar added for absorption (think Gatorade).

          While so many horse owners focus on minerals, few seem to understand the importance of adding back the lost protein in horses either chronically deprived of broad spectrum amino acids in the diet or the chronic loss of amino acids from self absorption (gluconeogenesis). Minerals are transported across the gut wall and distributed within the body by proteins. For example, hemoglobin is a protein with iron incorporated into it for transport of oxygen to cells via red blood cells. Deficiency in just one amino acid causes a depletion of so many proteins just like a dictionary missing one letter prevents the use of a bunch of words (no “W” and you can’t write the sentence “Where will we be tomorrow?”).

          Soy bean meal is safe in horses with no reported evidence of illnesses from genetic modification nor feminization from estrogens. It is a legume which are accepted by horses as are all other legumes such as alfalfa and peanuts. As a meal, the lectin containing hulls have been removed and the inflammatory oil has been removed. I would dare say that the feminization of stallions by castration is more extreme than any SBM diet could dream of. But more importantly than knowing that genetic modification has occurred in 94% of all foods consumed is the observation that most of the horses I see across this country show chronic protein deficiency. If you want to add non-GMO SBM that’s fine and it does exist. There are also other sources of amino acids.

      2. When you say ground water, do you mean “Well” water? My water is not from a well, it is from a public source. (started the “no grain” Feb 11, 2019) ALSO, Wondering do horses become depleted of vit-min from hard work? I do 3 Day Eventing. Thank you.

        1. Yes, ground water is well water. Treated water may have some of the minerals removed and others added such as chlorine and fluoride.

          Hard work in warm weather may cause a depletion in electrolytes. If it is severe then “thumps” may occur. However if you horse has access to minerals, the electrolytes lost will be restored.

          Vitamins are proteins and like all proteins, they have a half-life of 2 to 4 days. Exercise may shorten the life span of some connective tissue protein as well as vitamins and other proteins due to stress and cortisol. But actually exercise will demand more amino acids due to the horse building more connective tissue to support the forces applied to it. Most human exercise gurus suggest ingesting the protein supplementation within 1 hour post exercise. I would assume this to be true for horses though I have not read this. However the routine ingestion of maintenance protein should be adequate for vitamin production. Remember a healthy gut microbiome is important for many vitamins to be made.

    1. Pasture, hay, water, Himalayan salt, ProAdd (Nutrena). I could easily replace ProAdd with soybean meal without vitamins and minerals, but for our area this is just easier.

      1. I’m trying to help 5 horses that only get fed once a day, have not hay or good pasture. The pasture is overgrown with very tall weeds, trees, etc. I bought a mineral block for them. I’m concerned about the youngest which is maybe 1-2 years. The owner gives them sweet feed. I’m trying to work with them so we can have someone foster them and find homes for them. They is the mom and 3 of her babies which are probably 5, 3 and 2. They are beautiful paint mares with red and white exceptional markings and the youngest is a pretty sorrel mare. They have gained weight but have bellies on them. Is there anything I can do to to help the youngest. I don’t want her growth stunted.

        1. Stop feeding grain and replace the mineral block (high in sugar) with a mined salt lick. Add grass hay with a flake of alfalfa per day. Add 1 pound soybean meal per 1200 pound horse per day. Record everything you do with the observations you see. If doing this is impossible in their situation then get them to another place where you can control their feeding.

          Remember “gaining weight” is often a sign of inflammation. Please read all the blogs here and consider enrolling in the nutrition course to fully understand how to feed horses. Thanks, Doc T

  7. Informative article! I basically came to the same conclusion after years of dumping tons of money into mineral/vitamin supplements, testing hays to see what was missing, etc., etc. I quit supplementing and went back to the basics. I was never a supporter of feeding grain to my horses so don’t think I ever really did or if I did it was minimal, which may explain why they don’t look or act their age. My horses (ages 28 & 30) seem to be doing better now that I cut everything out. I do have a Redmond’s salt rock and some loose mineralized salt that they can eat or not. Someone recommended a product called Thrive Feed to me ( – are you familiar with it? If so, your thoughts? Based on your article, I think I know what your response might be. Thanks!

    1. Thanks Lorraine – Remember, It’s what you take away, not add. Though I am an advocate of adding protein to most horses due to the chronic protein deficiency.

      Thrive seems to have its heart in the right place. But there are some things I would not feed based on their ingredients which are “Dehydrated alfalfa meal. Timothy grass meal. Grain sorghum. Whole soybean meal. Rice bran. Dried kelp meal. Calcium carbonate. Salt. Schidigera extract. (Yucca) L-Lysine monohydrochloride. DL-methionine. Potassium sulphate. Magnesium sulphate. Monodicalcium phosphate. Diatomaceous earth. Zinc sulfate. Ferrous sulfate. Copper sulfate. Calcium iodate. Cobalt carbonate. Vitamin E supplement. Niacin. D-Calcium pantothenate. vitamin A supplement. Thiamine mononitrate. (source of Vitamin B2) vitamin B-12 supplement. D-Activated animal sterol. (source of vitamin D-3) Pyridoxine hydrochloride. (source of vitamin B-6) Folic acid. Menadionine sodium bisulfite complex. Manganese methionine complex. Cobalt glucoheptonate.”

      What I like is alfalfa, timothy and soybeans (and salt). Keep it simple. What I possibly don’t like is the sorghum as many think this is a resistant starch in humans. The rest are supplemental and as you read, I think most of these in a healthy horse are unproven in their beneficial effects. Thanks again for posting and telling everyone about your vibrant elders.

      1. Thank you for your reply, much appreciated! Yes, there are a lot of ingredients I don’t like either. The recommendation was made because my horses’ molars are almost completely gone so they can’t eat enough hay to maintain their weight. They have access to Bermuda (only hay both can eat without a problem) 24/7 to keep them ulcer free and busy; plus they are supplemented with Timothy/alfalfa soaked pellets.

        1. All they will need is pasture, hay (cubes or chopped so they don’t need perfectly functioning cheek teeth) and protein. It is the protein that seems to be forgotten (see the previous pillar 8 blog). Also, to maintain some fat on these elders, you can add coconut meal (Coolstance – or, if you can’t get that, Renew Gold (which has Coolstance in it). This will add the extra calories for winter in older horses without adding inflammation.

          1. Thanks again. They wad all pasture type hay (and any long-stem hay) and would not eat the CoolStance I bought for them a couple of years ago. I also tried chopped hay and they wouldn’t eat that either (tried 4 different brands). I’ve not tried cubed hay because it would have to be soaked and based on the chopped hay experience I doubt they’d eat it (I tried soaking regular hay and they wouldn’t eat it). They are definitely challenges to feed!! Feeding soaked pellets (Timothy/alfalfa mix) – they’ll eat them and it keeps their weight up – and 24/7 Bermuda hay seems to be the best combo I’ve found. So, looks like protein and fat are what they’re missing. I’m afraid they won’t eat the Renew Gold because of the CoolStance in it. I just hate buying things and having to throw them out because the guys won’t touch it. Will go back to your articles on protein and fat and see what I can add. These horses are really lucky (people tell me this all the time) that I spend so much time figuring out how to keep them healthy and happy!! That’s why, other than all the white hairs, they look and act 5-10 years younger than they really are. 😀

          2. Adding fat is usually inflammatory. Coconut meal and their fat are NOT inflammatory.

            Horses get their fat from cellulose. Please read The High Fat Diet to learn about this. Adding oils is NOT helpful.

            As far as them “not liking” the hay types you bought them, if it gets cold enough and they get hungry enough, horses will eat down the wood of the barn. Believe it or not, once they start to eat what is good for them (grass / hay (any form)) they will actually keep their weight on. Remember that the definition of “weight” is mass times acceleration. What makes that mass is protein, fat, muscle, minerals, water and gas. Horse owners often confuse “weight” with just fat but in reality, as the horse loses fat the true loss of muscle is seen.

            You are in the best time of year to do these additions for your horses. No added fat necessary because they will get that from the grass and fresh hay. Add 1 gram of effective protein (NOT crude protein) per pound on body weight (about 1 pound of a good soy bean, whey protein and alfalfa mix) per day. Do this for all summer and then evaluate these horses before winter sets in. I’ll bet they will look even better than they do now – and do well over the winter.

  8. This article about vitamins, minerals, etc was very interesting and helpful…investing in good pasture and hay makes good sense!!!