Chia is familiar to many horse owners. This small seed has been used in horse feeding for years – but what does it actually contain, and why is its nutritional profile so interesting for horses?
The benefits and strengths of chia do not come from one single nutrient. The same small seed combines protein and essential amino acids, an exceptionally high omega-3 content, fibre and water-binding mucilage, as well as naturally occurring antioxidant compounds. Chia seeds typically contain around 15–25% protein, 30–33% fat and a substantial amount of dietary fibre. [1]
Let’s take a closer look at what is known about these nutrients – and why they matter in horse nutrition.
1. Protein – but above all, amino acids
When assessing a horse’s protein intake, it is easy to focus on the crude protein percentage of the feed.
However, that does not tell the whole story.
Proteins are made up of amino acids. The horse’s body needs them for building and renewing muscles and other tissues, as well as for producing enzymes and many other proteins in the body.
Some amino acids are essential amino acids, meaning that the horse must obtain them from the diet.
The protein in chia seeds contains all essential amino acids, including lysine, which is particularly important in horse nutrition. [1]
Why is lysine so important?
Lysine is considered the first limiting amino acid in horse nutrition. In simple terms, this means that the amount of lysine available can limit how efficiently the horse’s body can use other dietary amino acids to build new proteins. [2]
A high crude protein content therefore does not automatically guarantee optimal protein nutrition.
In addition to the amount of protein, its quality matters – in other words, which amino acids the protein contains.
The importance of lysine has also been studied directly in horses.
In a study involving young horses, different levels of lysine intake affected amino acid metabolism and whole-body protein synthesis. The findings support the central role of lysine in protein metabolism in growing horses. [3]
In another study, young horses were supplemented with lysine and threonine. Amino acid supplementation was able to support growth even when the overall protein content of the diet was lower. This illustrates well that amino acid composition matters – protein percentage alone does not determine everything. [4]
The subject has also been studied in adult and older horses. In one study, an amino acid supplement containing lysine and threonine improved measures related to muscle mass in both younger and older horses. [5]
Protein percentage does not tell the whole story.
What matters to the horse is also which amino acids the protein contains.
Chia is not a concentrated amino acid supplement, but it naturally provides plant protein and, with it, essential amino acids such as lysine.
2. Exceptionally rich in plant-based omega-3
If chia is known for one nutrient in particular, it is usually omega-3.
And for good reason.
Around one-third of a chia seed’s weight can consist of fat, and its fatty acid profile is exceptional. Approximately 60% of its fatty acids may consist of alpha-linolenic acid, or ALA omega-3 fatty acid. Chia also contains linoleic acid, an omega-6 fatty acid. [1,6]
Both alpha-linolenic acid, or ALA, and linoleic acid are essential fatty acids for horses. Horses cannot produce them themselves and therefore need to obtain them from their diet. [7]
Why is omega-3 interesting for horses?
Fresh grass, a natural part of the horse’s diet, is rich in omega-3 fatty acids. However, the fatty acid composition of the overall diet changes depending on which feeds it consists of.
Seeds rich in ALA omega-3 are one way to supplement this aspect of the diet.
And with omega-3, it is not only about what the feed contains. Research has shown that the fatty acid composition of the diet is also reflected in the horse’s body.
In an 18-week study in horses, a diet containing ALA omega-3 clearly altered the fatty acid composition of blood plasma. [8]
Later studies have confirmed this finding: different plant-based fatty acid sources alter the fatty acid profile of horses’ plasma. [9]
In a study published in 2025, the effects of ALA-rich fat were followed even further. The proportion of omega-3 fatty acids in the fatty acid profile of the horses’ skin increased during the feeding period, showing that dietary fatty acids were also reflected at tissue level. The study did not, however, find differences between the oil groups in the measured immune or inflammatory responses. [7]
The research therefore gives good reason to pay attention to the fatty acid composition of a horse’s diet.
Chia’s strength here is very simple:
it is one of nature’s richest plant-based sources of ALA omega-3 fatty acids.
3. Fibre – one of chia’s less well-known strengths
Omega-3 often gets most of the attention, even though chia is also a very fibre-rich seed.
Studies have reported a dietary fibre content of approximately 18–35% or even more, depending on the raw material and the analytical method used. [1,6]
Chia contains both insoluble and soluble fibre.
Fibre plays a particularly important role in the horse. Its digestive system has evolved to utilise a fibre-rich, plant-based diet, and microbes in the caecum and large intestine break down fibre through fermentation.
This fermentation produces, among other things, short-chain fatty acids that the horse can use as an energy source.
Chia therefore provides more than just protein and fat. As a whole seed, it also contributes a significant amount of dietary fibre.
4. What makes chia form its characteristic gel?
This property of chia is easy to see for yourself.
When chia seeds come into contact with water, a transparent, gel-like layer quickly forms around them.
This is mucilage – a polysaccharide-rich soluble fibre material found on the surface of the seed.
Research indicates that chia seeds contain around 5–6% mucilage. That may sound like a small amount, but its ability to bind water is exceptional. [10]
In one study, isolated chia mucilage was able to retain up to approximately 27 times its own weight in water. [10]
This is why chia so quickly develops its characteristic gel-like texture when it comes into contact with liquid.
It is not simply a matter of the seed “absorbing water”; the fibre structure on its surface forms a water-binding network.
It is this mucilage that distinguishes chia from many other seeds that are also rich in fat and protein.
5. A small seed packed with nutrients
Ultimately, what makes chia interesting is not one single property.
Within one seed, it combines something that is quite unusual for a single feed ingredient:
plant protein and essential amino acids – including lysine, abundant ALA omega-3, omega-6, dietary fibre and chia’s characteristic water-binding mucilage.
Chia also naturally contains minerals and various phenolic, antioxidant plant compounds. [1,6]
Chia is therefore much more than simply an “omega-3 seed”.
It is a nutritionally diverse feed ingredient – and when you take a closer look at what it actually contains, it is easy to understand why this little seed has maintained its place in horse feeding year after year.
References
1. Hrnčič, M.K. et al. (2020). Chia Seeds (Salvia Hispanica L.): An Overview—Phytochemical Profile, Isolation Methods, and Application. Molecules 25(1):11.
Comprehensive review of chia seed nutrition, including protein, fibre, fatty acids, minerals and bioactive compounds.
2. Mok, C.H. et al. (2020). Amino acid requirements in horses. Asian-Australasian Journal of Animal Sciences 33(5):759–765.
Review of amino acid requirements in horses and the role of lysine as the first limiting amino acid.
3. Mastellar, S.L., Coleman, R.J. & Urschel, K.L. (2016). Controlled trial of whole body protein synthesis and plasma amino acid concentrations in yearling horses fed graded amounts of lysine. The Veterinary Journal 216:93–100.
Study examining the effects of lysine intake on protein synthesis and amino acid metabolism in young horses.
4. Graham, P.M. et al. (1994). The effect of supplemental lysine and threonine on growth and development of yearling horses. Journal of Animal Science 72(2):380–386.
Study on the effects of lysine and threonine supplementation in growing horses.
5. Graham-Thiers, P.M. & Kronfeld, D.S. (2005). Amino acid supplementation improves muscle mass in aged and young horses. Journal of Animal Science 83(12):2783–2788.
Study investigating the effects of an amino acid supplement containing lysine and threonine on muscle mass in horses.
6. Kulczyński, B. et al. (2019). The Chemical Composition and Nutritional Value of Chia Seeds—Current State of Knowledge. Nutrients 11(6):1242.
Review of chia seed composition, with particular focus on fibre, protein and its high ALA omega-3 content.
7. Hartwig, S. et al. (2025). The effect of dietary camelina, flaxseed, and canola oil supplementation on skin fatty acid profile and immune and inflammatory responses in healthy adult horses. Journal of Animal Science 103: skaf025. DOI: 10.1093/jas/skaf025.
Study investigating how ALA-rich diets affect skin fatty acid composition and immune and inflammatory responses in horses.
8. Hansen, R.A. et al. (2002). Effects of dietary flaxseed oil supplementation on equine plasma fatty acid concentrations and whole blood platelet aggregation. Journal of Veterinary Internal Medicine 16(4):457–463.
An 18-week equine study examining the effect of an ALA omega-3-rich diet on blood fatty acid composition.
9. Burron, S. et al. (2023). Effects of dietary camelina, flaxseed, and canola oil supplementation on plasma fatty acid concentrations and health parameters in horses. Animal 17(12):101034.
Study on the effects of plant-based fatty acid sources on plasma fatty acid profiles in horses.
10. Muñoz, L.A., Cobos, A., Diaz, O. & Aguilera, J.M. (2012). Chia seeds: Microstructure, mucilage extraction and hydration. Journal of Food Engineering 108(1):216–224.
Study of chia mucilage structure, quantity and water-binding capacity; its water retention capacity was reported to be approximately 27 times its own weight.
