Magnesium is one of the essential minerals in a horse's diet. It plays an important role in the normal functioning of the nervous system and muscles and is involved in numerous metabolic processes throughout the body.
Its importance has also attracted interest in the nutrition of sensitive, easily stressed and highly reactive horses.
Magnesium occurs naturally in many plant-based feed ingredients, including chia seeds. Chia is a particularly interesting addition to a balanced equine diet because, alongside magnesium, it provides omega-3 fatty acids, fibre, protein and other naturally occurring nutrients.
What does research tell us about magnesium and equine behaviour, and how can we ensure that horses receive enough magnesium through their diet?
Magnesium is essential for the horse's nervous system and muscles
Magnesium is involved in hundreds of enzymatic reactions and is essential for normal metabolism.
It contributes to several important physiological functions, including:
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Transmission of nerve impulses
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Muscle contraction and relaxation
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Energy metabolism
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Protein synthesis
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Maintenance of normal bone structure
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Electrolyte balance
Magnesium works closely with other minerals, particularly calcium.
The normal functioning of nerve and muscle cells relies on a complex interaction of electrical and chemical signals, in which magnesium plays an important role.
This is why an adequate magnesium intake is essential for horses of all ages, whether they are leisure horses or actively trained sport horses.
Can magnesium influence a horse's stress sensitivity?
The relationship between magnesium and equine behaviour has been investigated by researchers at Charles Sturt University in Australia.
A study published in 2015 examined the effects of dietary magnesium aspartate supplementation on horses' reaction speed.
The researchers observed an interesting result: horses receiving a higher magnesium supplement showed a slower reaction speed during testing than when they received no additional magnesium.
The reported average reaction speeds were:
| Feeding condition | Reaction speed |
|---|---|
| No magnesium supplementation | 5.3 m/s |
| Lower magnesium supplementation | 3.7 m/s |
| Higher magnesium supplementation | 3.1 m/s |
The difference between the higher magnesium dose and the control condition was statistically significant in one of the study comparisons.
These findings attracted interest because they suggested a possible relationship between magnesium intake and equine reactivity.
A follow-up study published in 2018 investigated the effects of magnesium supplementation in horses of different breeds.
The researchers observed individual differences in responses, although the study did not demonstrate the same statistically significant effect across the entire group.
Together, these studies highlight magnesium and equine behaviour as an interesting area of nutritional research.
An adequate magnesium intake remains essential for normal nervous system function, even though the behavioural response to additional supplementation may vary between individual horses.
Chia is a natural source of magnesium
Chia seeds (Salvia hispanica) naturally contain magnesium.
Chia de Gracia's chia seeds provide approximately 360 mg of magnesium per 100 g.
Alongside magnesium, chia seeds contain plant-based omega-3 fatty acids, protein, essential amino acids and dietary fibre.
This nutritional diversity is one of chia's greatest strengths. A single natural feed ingredient contributes several nutrients important for normal physiological function.
How much magnesium does a serving of chia provide?
Based on the magnesium content of Chia de Gracia chia seeds:
| Chia seeds | Magnesium |
|---|---|
| 25 g | 90 mg |
| 50 g | 180 mg |
| 75 g | 270 mg |
| 100 g | 360 mg |
A mature horse weighing 500 kg typically requires approximately 8–15 grams of magnesium per day, depending on factors such as workload.
The magnesium provided by a normal serving of chia therefore contributes to the horse's daily mineral intake, although it represents only a small proportion of the total requirement.
Chia is primarily a nutritionally diverse feed ingredient, with magnesium being one of its many naturally occurring nutrients.
For more information about chia's nutritional properties, read Chia in Horse Feeding – Why Is This Little Seed So Nutrient-Dense?.
When might a horse need more magnesium?
A horse's magnesium requirement depends on factors such as body weight, age, workload and physiological condition.
Magnesium is normally supplied through forage and other daily feeds. However, magnesium concentrations can vary considerably between forage batches, making it important to assess the total dietary intake.
Horses in regular training generally have higher magnesium requirements than horses at maintenance. Some magnesium is also lost through sweating.
Approximate daily magnesium requirements for a 500 kg horse
| Activity level | Magnesium per day |
|---|---|
| Maintenance | Approximately 8 g |
| Light work | Approximately 10 g |
| Moderate work | Approximately 12 g |
| Heavy work | Approximately 15 g |
These values are general estimates. Individual requirements may vary according to the overall diet, workload and physiological condition.
If the horse's forage and other feeds do not provide sufficient magnesium, a concentrated magnesium supplement can be used to complete the diet.
The balance between minerals is also important. In addition to magnesium, the intake of calcium, phosphorus and other essential minerals should be considered.
Looking at the whole diet of a stress-sensitive horse
A horse's behaviour is influenced by many different factors.
Temperament, training, environment, daily exercise, herd relationships and possible physical discomfort can all affect how a horse responds to different situations.
Balanced nutrition is another important part of overall wellbeing.
Providing enough good-quality forage, meeting energy requirements and ensuring an adequate intake of essential nutrients all contribute to normal physiological function.
The nervous system also depends on several nutrients besides magnesium.
For this reason, it is worth considering the entire diet rather than focusing on one individual mineral when planning the feeding programme of a sensitive or reactive horse.
If a horse's behaviour changes suddenly or significantly, possible health-related causes should also be investigated.
Chia or a concentrated magnesium supplement?
Chia seeds and concentrated magnesium supplements have different nutritional roles.
Chia Seeds provide magnesium alongside omega-3 fatty acids, fibre, protein and other naturally occurring nutrients.
They can therefore be a useful part of a varied daily feeding programme.
When a horse requires a larger amount of additional magnesium, a concentrated supplement is a more practical option.
CdG Organic Magnesium is designed to complement a horse's daily magnesium intake with a high concentration of magnesium in a small serving.
A serving of approximately 14 grams provides around 4.8 grams of magnesium.
This allows magnesium intake to be adjusted according to the horse's individual requirements and the amount already supplied by the regular diet.
For a more detailed explanation of magnesium and its physiological roles, read Do You Know What Horses Need Magnesium For?.
Summary – magnesium is an important part of equine wellbeing
Magnesium is an essential mineral that horses need every day for normal nervous system function, muscle activity and metabolism.
Its potential relationship with stress sensitivity and reactivity has attracted scientific interest.
A study published in 2015 observed slower reaction speeds in horses receiving magnesium supplementation, providing an interesting starting point for further investigation into the relationship between magnesium and equine behaviour.
Chia seeds naturally contain magnesium alongside several other valuable nutrients. They can be included as part of a balanced diet, while a concentrated magnesium supplement can help meet a larger nutritional requirement when necessary.
An adequate magnesium intake, good-quality forage and attention to the horse's individual needs provide a sound nutritional foundation for normal nervous system and muscle function.
References and further reading
1. Magnesium aspartate supplementation and reaction speed response in horses (2015).
Journal of Equine Veterinary Science, 35, conference abstracts.
The study investigated the effects of magnesium aspartate supplementation on reaction speed in horses. Slower reaction speeds were observed with the higher magnesium dose compared with the control condition.
https://equifeast-australia.com/content/Magnesium_aspartate_supplementation_and_reaction_speed.pdf
2. Does oral magnesium aspartate supplementation affect reaction speed in horses of different breeds? (2018).
Comparative Exercise Physiology, 14(Suppl. 1), S74.
A study investigating the effects of magnesium aspartate supplementation on reaction speed in horses of different breeds.
https://doi.org/10.3920/cep2018.s1
3. National Research Council (2007).
Nutrient Requirements of Horses, 6th Revised Edition. National Academies Press.
A scientific reference covering equine magnesium requirements, mineral metabolism and nutritional needs.
https://doi.org/10.17226/11653
4. Ullah, R. et al. (2016).
Nutritional and therapeutic perspectives of Chia (Salvia hispanica L.): a review.
Journal of Food Science and Technology, 53, 1750–1758.
A review of chia's nutritional composition, including minerals, fatty acids and other naturally occurring nutrients.
https://doi.org/10.1007/s13197-015-1967-0
