Decomplexicating Equine Nutrition Part 11 of 12 – Lectins

This Is Really New Stuff

The things I will be writing about here are mind-blowing – and very new. I am excited about this information for a lot of reasons but the most important for horse owners is that lectins are, for the most part, not good. For example, about 5 and 6 years ago a Nobel prize was awarded for research on lectins as a cause for making insulin ineffective. Can anyone say insulin resistance (again)?

Lectin is a new word for many of you but scientists have known about them for a while. A lectin is a protein made by plants. OK so far? Let’s start by telling you what lectins do.

We all know about the immune system within ourselves that defend against attacks by bacteria, viruses and other bugs trying to take over our bodies but did you know that plants also have a system to prevent attacks? Further, did you know that many plants do not want to be eaten? This especially applies to their “babies” or what we non-botanists call seeds. During the 100,000 to 200,000 years humans have been Homo sapiens (modern humans), and I assume horses too, we have learned to live with certain plants willing to become our food without the predator becoming sick or dying from them. This is usually because of a win-win relationship. For instance, the horse eats the grass and then defecates on the grass which in turn fertilizes the grass to help it grow. In addition, as they walk they knock off the seed heads and carry them on their wet legs which helps to spread the seeds.

Examples of defenses made by plants to prevent their demise from predators include thorns (cactus, roses), irritating substances (poison ivy), and toxins (rhubarb leaves, belladonna). But they also can be more subtle in their attack. One of the most notorious lectins is gluten which slowly causes illness in humans especially susceptible people with celiac disease. Gluten is by far not the most offensive of subtle lectins. There are worse and we are just learning about them.

Remember that anything you place into your mouth and swallow is NOT inside of you. The food you eat (raw material) feeds the bacteria living in your gut creating the fuels (glucose and short chain fatty acids) that allow the mitochondria to make the energy to run the cells. When some new raw material is introduced to the gut that has a new foreign protein (a lectin), an alert is sent out to our immune system. The first line of defense is the slippery and sticky mucous covering the gut lining which binds to these foreign proteins and escorts them out of the gut without damage. This includes the mouth and nasal passages too. Ever get a stuffed-up nose when eating something spicy? That is the response to a lectin.

The mucous is actually a mucopolysaccharide. Polysaccharide is a string of sugar molecules and “muco” means it is made by the mucous membranes that line the gut. The sugar (polysaccharide) binds to these lectins. As a side note, guess what chondroitin is in the joint supplements you feed your horse? It is an oligosaccharide which is a sugar that binds to the lectins that cause joint inflammation. These supplements work in the gut and not in the joints. But guess what? If you produce enough mucous, it will also do this job making the chondroitin supplementation unnecessary.

But when there are 1) a lot of these many different lectins and 2) a lot of dead good bacteria (lipopolysaccharides) from the high carbohydrate feedings, then damage to the gut lining occurs and mucous production is reduced or overwhelmed. The end result is a leaking gut due to the breakdown of the tight junctions as well as a breakdown of the primary defense system against lectins. Of course, this leads to a horse that is less than perfect in all aspects of health.

Where Did The Bad Lectins Come From?

Humans found that we could grow grains and store them making them available for use in winter when food was scarce. It is interesting to note that there is no evidence of osteoarthritis in bones found in archeological sites until the Egyptians and the Pharos. And guess who ate more grains than any other human on Earth? Yup – the Egyptians. The development of grains as a crop started about 8000 years ago in the “fertile crescent” of land between the Tigris and Euphrates Rivers in the land now known as Iran. The Egyptians further developed the use of grains, especially wheat, and became the leaders in its use to store this raw food for eating through the dormant months or droughts. It is the development of grains and grain storage that directly led to the expansion of civilizations (Egyptian, Greek, Roman, Mongolian, Viking etc) and the movement of exploration of man across the globe (Columbus et al). The diseases of man today including osteoarthritis, atherosclerosis and diabetes are seen in the mummified Egyptian remains but not in remains of man prior to 10,000 years ago.

The lectins of wheat are now well known including the common gluten and the more destructive cousin Wheat Germ Agglutinin (WGA). Then explorers such as Columbus brought back with him new foods such as tomatoes, squash, cucumbers, peppers and eggplant with lectins that are particularly destructive. Yes, only 500 years ago our gut bacteria were introduced to the lectins of these plants from the group of plants called nightshades (by the way, they are NOT vegetables but actually fruits) and their associated destruction of our gut lining and subsequent disease effects such as insulin resistance, diabetes and obesity soon followed.

Horses became domesticated about 4000 years ago because our expansion of civilizations, wars against neighbors and exploration of faraway lands required their use. Feeding them grains seemed logical as horses were often kept in places without pasture such as boats for ocean crossings or fenced-inBy areas for ever-ready use against enemies. Making hay was not efficient as hay farming techniques and the shipment of hay are recent developments.

The Damage By Lectins

The direct damage to the tight junctions of the gut lining caused by the invading foreign proteins creates a space between the cells where more lectins can move right into our body. The term describing this is leaking gut and lectins have been shown to be a primary cause of the leaky gut syndrome. The more damage, the more foreign invaders, the more inflammatory immune response, the more disease and ultimately, the fewer number of these animals eating the plant and therefore the better chance for the plant to survive.

In horses, the introduction of grains as a popular feed for all horses everywhere is only at most 50 years old. In 1973 as a stall mucker I would go to the railroad yard with the other workers and unload a box car full of high-quality oats. It was a tough day and it was certainly harder than the ability of you today to pick up the phone and order a few bags of that fancy feed with the pretty pictures, catchy name and a back panel filled with unpronounceable words – and STACKED IN YOUR FEED ROOM by the strong delivery person! Add to this the increasing cost of hay and the decreasing availability of pasture. Grain is becoming a more cost-effective option and a more efficient way to feed the horse. But this is from the human perspective. But from the perspective of the gut microbes of the horse, it is becoming lethal.

An important fact about lectins is that they are found in the outer layers of grains. This is why the white bread of sourdough, French baguettes and Italian bread have the least amount of lectins. They use wheat that has the outer layer removed. This outer layer is the bran and middlings that are collected and fed to your horses. Did you know that back in medieval times the wealthy noblemen ate white bread while the poorer peasants not affording the process of stripping off the outer layers to make white bread were left to eat the whole grain bread? These peasants historically had more diseases. Rice is also a grain and its lectins are also in the outer layer. Most people in Asian countries where rice is the main starch remove this outer layer before eating their rice. This may make you pause the next time you order brown rice or feed your horse a mix with rice bran in it.

Most people don’t feed the nightshade fruits to their horses, but it is interesting to know that every good Italian removes the skin and seeds of the tomato before eating them. They learned a long time ago that removing these lectin-laden parts ended their illnesses caused by eating this new food that Columbus brought back from the new world.

Lectins and Disease in Horses

Most of the diseases so popular today in horses were uncommon back before grain became abundantly available. In fact, reading the vet texts written in the late 1800’s you will find little of what we see today in the form of illness. While not the only change, the most common and persuasive change seen throughout this country in the care of the horse is the introduction of abundant and readily available grain with their associated foreign lectin proteins and high carbohydrate (starch) content. Please understand that this is only a hypothesis based on human research but for me and what I am seeing around the country, it explains why so many horses that are removed from grain show such positive improvements. At the very least, they seem calmer and more willing to do their jobs and exist in the human world we have created for them.

What about whole grains like the racehorse oats that we fed 45 years ago? While a no-grain approach is the safest, if you just can’t stop feeding grain (extreme weather for instance), first go no-grain for at least 6 weeks to allow the full healing of the gut and the re-establishment of the good gut bacteria. Then, if you are looking for something to add, try adding extra protein if it is a top line or a better hoof you are looking for. Then, for added fat, go with whole grains such as oats. Use only enough whole grains to meet a need and stop feeding it when that need is no longer necessary such as the availability of spring pasture. In my experience, though the results from a no-grain diet will stop you from ever feeding grain again in almost all circumstances. (See the article in “The Horse” titled “Racing Standardbreds on an all forage diet”).

Remember, almost every grain mix sold today is filled with byproducts with the lectin WGA ladened wheat middlings the most prevalent. All the byproducts including all the brans (wheat, rice) and hulls (oat, soy) and pulp (sugar beets) are the outer layers where the lectins are most abundant. In other words, feeding byproducts is feeding concentrated lectins. In addition, other soft seeds are also fighting for survival against predators eating them. Soft seeds include all grains but don’t forget sunflower seeds, flax seeds and any other seed in grain mixes. These too will have lectins that may be disrupting the gut lining. While there is no scientific evidence of this yet, why feed something to your horse he would never eat (at least continually) in the wild?

As a comparison, an example of a hard seed is a peach. When the fruit becomes ripe, 3 things happen. First, the color of the skin changes and this is most likely what we developed color vision. Second, the lectins in the skin that make the fruit bitter are removed by the plant allowing our taste buds to accept the fruit. Third, the glucose within the fruit is converted to fructose which is a better sugar to create fat in our bodies. In addition, fructose is less stressful on insulin which is beneficial to that system, but fructose is more efficient in adding fat. Does anybody want a glass of orange juice??? The benefit of eating the ripe hard seed is that we become fatter for the upcoming winter and the seed is thrown away which perpetuates the peach tree. Win-win.

There are no hard seeds for horses to eat and this is the reason, possibly, for them not having good color vision. There may be an exception and this would be coconut. The meal made from the meat of the coconut has been shown to be beneficial and noninflammatory in humans and may even be a prebiotic for good gut bacteria. It is commercially available for horses and I recommend coconut meal for horses needing a source of noninflammatory food. An example would be for a horse 25 to 30 years old that when the grain is removed their bodies seem to not respond right away. Coconut meal adds the food needed to add condition to these elder horses.

What we know is absolutely safe for horses is simply feeding them what grazers were made to eat – grass and plants low to the ground. If they consumed their seeds it was only for a short time of the year. The concentrated feeding of wheat, oats and other grains was not an option until humans harvested them and fed only the seeds to the horse. The remaining straw (oat straw, wheat straw, rye straw) is not preferred by the horse and is only eaten when there is no pasture or grass hay available.

This information is well ahead of most articles on equine nutrition. It is only about 5 years old in human nutrition. In horses, the discussion on the gut microbiome has started and at some point, it will expand to lectins. Until then, if you remain skeptical about the effects of lectins it’s OK. Removing grain and grain byproducts to reduce the effects of carbohydrate dependency is good enough. But as you remove these you are also removing the lectins. I’m good with that.

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  1. This is really good! I have been following Plant Paradox way of eating for 9 months and have seen a significant reduction in pain in my knees and finger joints as well as improved energy throughout the day. Having seen these improvements in myself I got to wondering about the horses and this article answers a lot of my questions. I just have a couple left. You mention chia seeds as a side-note but didn’t really address them. Just by feeding what grazers naturally eat, I am guessing you would say not to feed them to horses. We have been, but primarily as a way to help prevent sand colic. My research says they are high in lectins. We bring our mares in about every other day to inspect them, groom them, and doctor any sores they may have. We give them a scoop of timothy pellets with some chia seeds in it when we bring them in. We live in florida and keep our horses on pasture, but of course there is sand everywhere! How would you suggest we deal with sand-colic prevention? I have read that plentiful hay is the best preventative of sand-colic but we can’t get our mares to eat any hay in the summer when the grass is plentiful. Also, legumes are high in lectins as well and alfalfa is a legume. Do you discourage alfalfa hay? .

    1. I agree that feeding chia or any soft seeds may not be good for horses.

      Horses can eat legumes (alfalfa, soybean meal, peanut hay) with none of the effects of legumes in humans. Remember we are very different in our gut systems so legumes are OK for horses.

      The prevention of sand colic, in my opinion, is having a healthy gut microbiome. Feeding forage (pasture and / or hay) without the inflammatory ingredients of grain and byproducts (loaded with lectins) should maintain a healthy microbiome.

      I too live in FL but I see a lot of sand in Long Island NY as well as every other coastal state. Elephants also get sand impactions (my zoo vet friend has told me). But I think the Arabians from Arabia have us all beat! If the gut is healthy then the horse is healthy. Thanks for reading all my blogs and commenting too.

  2. Hi, Thanks for your information. I was about to add more soy hulls as a fibre source, until i read this. I was trying to find a way to extend my hay as the drought is so bad & hay is getting harder to come by & very expensive. (Australia – Qld, NSW etc). I’ll drop the rice bran too & just feed the copra meal (coconut) & soy bean meal. I was wondering if chick pea & faba beans have the same issues? Thanks Andrea

    1. Good question. I’m not sure as these are not common in America but as an added source of fiber, maybe. All beans have issues in humans but chick peas are a legume and should be OK for horses. Faba beans (fava beans) are OK for humans only after their outer shell is removed through parboiling them. Unfortunately I have no advice using these in horses. You should join the private Facebook group “The Horse’s Advocate” and ask people there this question. 🙂

      1. Thanks Geoff. I’ve been trying to do some research on cooked lectins – would steam extrusion or micronisation reduce the lectin issue, or does it still cause gut issues with the starch? Thanks Andrea 🙂

        1. Cooking under pressure and fermentation can destroy many lectins but the best way to eliminated lectins is to avoid them. Feed forage and supplement with protein plus water and salt.

          1. Thanks Geoff for your reply. It’s getting desperate times here with our severe drought & being able to keep up enough forage. We are limited to the amounts of Copra we can buy & lucerne prices are killing me. The horses are dropping away, especially my oldies, so trying to do something that stops them looking so bad, getting to the point that i just need calories to help them, but feel bad that it’s heading in the direction of using rice or barley to help. They’re on nearly a kilo of full fat soy bean meal & we’re struggling.

          2. When the fat (soybean oil) is left in the SBM then the oil can be inflammatory. This can lead to weight loss in some.

            When horses (or any animal) is in a stressed environment (drought, ice age, etc) then you need to feed whatever you can while avoiding any inflammation. For decades and longer, whole oats have worked as well as other whole grains such as barley. De-hulled whole grains will help to decrease the lectins. Once the drought is over (it can be a long tine) then you can return to all forage. Adding the SBM is just to restore the lost amino acids.

  3. this has nothing to do with what you have printed here, will read it soon, have a question, my gelding keeps getting abcesses front and back and (of course) he is on 12% pellet grain and hay, no pasture, we either have wet ground or dry ground. could it be a vitamine defintionsee? that is causing it. We try to keep place clean as possible, I am 78 and daughter is 51 and she works at a factory so I am left with keeping all(2 1/2) horses safe. He is the only one that has that problem. When he does, i put him in the arena with sand and when the corral is dry and he is sound I move him to the dirt. even dry on the dirt he gets them. he is not rode so he does a lot of standing eating a round bale and then moved to a stall over night for hay in there. Anyway you can give me a hint as to what might be the problem without you seeing him. I live in the middle of Delaware in low land. Thank you, Kathryn Krouse,

    1. Thanks Kathriyn – you need to add soybean meal at 1 pound per day per 1200 pound horse. You can even double this. It will take at least 1 year and up to 2 years to replace the hoof with stronger material to prevent abscesses.

      The 12% grain is weakening the hooves and it is not a vitamin deficiency. Please read about protein and the damage grain does at the other blogs:

      Consider joining the Facebook private group “The Horse’s Advocate” where a lot of your questions can be asked and answered. It is private so it is safe.

    1. Coconut oil is non-inflammatory in humans. It is an assumption that it is also non-inflammatory in horses as the interaction between oil and lipopolysaccharides should be the same in all animals. I only recommend shredded coconut (Coolstance) for underweight and older horses heading into winter. She view it as a protein source but I cannot confirm its bioavailability or its amino acid composition.

      Hemp is becoming popular now that this administration made it legal. It is another plant that needs more research in horses. If it is used as a protein source I would ask why when soybean meal is tried and tested and complete for all horses – and it’s inexpensive.

      The world is filled with solutions that we all add to fix something but in reality, life is beautifully elegant. Domestication has messed things up a bit. On occasion we need to step in with a solution but we must always be vigilant and note responses to these additional steps. We have not done this with the addition of grains, last summer’s grass (hay) and the plethora of supplements.

  4. Hi, what would you suggest as a good grain free hardfeed? I have been feeding Timothy chaff with a handful of soaked beet (to damp the supplements and make it tastier so they eat it). Would really like to cut out the beet though. I’m just reading plant paradox and finding it very interesting and I am feeling so much better after following the diet for just a week (even though I was already eating what I thought was a super healthy diet) which got me thinking about the horses too. Thanks

    1. Any hay pellet or hay cube should work. Add some water if you are worried about choke. A handful of hay pellets plus the soy beans meal works well with or without water.

      Be careful of the “supplements” as some have inflammatory ingredients and not all sources of these ingredients are verified.

      One of the reasons I recommend avoiding sugar beet pulp is that it is the outer part of the sugar beet where lectins reside. I’m glad you have read the Plant Paradox and now feel better after removing the inflammatory foods from your diet. The same will happen for the horses. Thanks!

  5. Great article on lectins! I recently became somewhat educated on lectins and their impact on humans. I did not know that Italians peeled their tomatoes and removed the seeds! I was wondering how Italians, with all their tomato-based foods, weren’t all very sick. Now I know!

  6. I just read all 11 posts you have made. Your reference to beet pulp (sugar beets), is that including pelleted beet pulp without molasses that should be avoided?
    The flax seed not being ideal has blown my mind. I am constantly learning, but anyone that has a horse with ulcers claims flax seed has helped them. Though, they changed a multitude of things at once.
    What are your thoughts on de-shelled pumpkin shells (peponitas)?

    1. Thanks for reading all of them (and there are a few more plus a whole course coming).

      There is one main principle here. Horses should only be eating what is available in their environment. If there are seeds and sugar beets available where they live then go ahead and feed them. But in humans we are now seeing lectin caused inflammation from all soft seeds. While I have no proof of this, I do know that flax, pumpkin and beets are not available to most grazing animals.

      Horses should be fed only what grazers eat when available for eating. Supplementing with grass cut in summer and preserved as hay is reasonable when how this works is taken into consideration.

      Please join me in the Horsemanship Nutrition course coming in about 2 weeks. Thanks again for your interest in a different approach to feeding horses.

  7. Geoff:

    Absolutely brilliant, as ever. If I could add only one comment, it would be that you tell people about beet pulp shreds as much as about coconut meal. While I wish I could wave a magic wand and have all horse owners & caregivers comprehend what you’re so eloquent about, my bet is this will primarily be read by nutritionists in feed companies! Oh well, if they actually react positively to this, you will have changed everything for the better from the horse’s perspective.
    How do we get veterinarians to pay attention?


    1. Thanks John. The feed companies and vets are paying attention, just not in the direction or in the amount that they should. Their approach is to take some of the big new shiny words (gut microbiome, pre-biotics, hind gut ulcers, insulin resistance and others) and spin vague rhetoric to continue the confusion. Add to this the enormous material in human nutrition work coupled with the belief that horses should eat what humans eat and the result is that chia seeds will fix everything.

      Cynicism is the bane of our age, so I chose optimism. Until I can no longer, I will continue to help horse owners sort things out to make choices that are in the best interest of the horse. And as my wife says, if I am thinking this then there are others. In time, our message will be heard.

      As always, I so appreciate your words and support.

      1. I think horse owners are reading your articles and it’s their response that will force feed companies to change. Only when grain or bad lectins are no longer in high demand will the feed companies bother to offer better alternatives. But it’ll be a constant battle because it always is. Thanks again for a wonderful article.

        1. Thanks Barbara – Like everything else, it will take clarity and consistency to help horse owners understand but as they do, they will change everything.