Coconut oil is a popular fat supplement for horses used to promote weight gain, skin health and a shiny coat.
It is also used as a cool energy source for exercising horses to add calories to the diet without relying on sugars and starches.
Coconut oil is derived from the kernel of mature coconuts that are harvested from the coconut palm tree. The two main types of oil obtained from coconuts are copra oil and virgin coconut oil. 
High-fat equine feeds are typically made with vegetable fats derived from canola, rice bran, soybean, and flax, but a growing number of products are now using coconut oil as an ingredient.
Coconut oil offers unique health benefits because it contains a high proportion of medium-chain triglycerides (MCT) which are a rapid source of energy.
Nutritional Profile of Coconut Oil
The digestible energy content of coconut oil is approximately 9.52 Mcal/kg (dry matter).
Coconut oil contains approximately 92% saturated fat, along with monounsaturated and polyunsaturated fats. 
Approximately 45 to 55% of the saturated fats in coconut oil contain lauric acid.  Once ingested, lauric acid is metabolized into monolaurin, an organic compound that has antimicrobial properties.
Fatty Acids in Coconut Oil
All fatty acids are composed of carbon, hydrogen, and oxygen atoms. They are classified according to their molecular structure as either saturated or unsaturated fats.
Saturated fat is made of hydrocarbon chains that are only connected by single bonds, whereas unsaturated fats are connected by one or more double bonds. 
Saturated fatty acids are also usually solid at room temperature (approximately 20 oC/68 oF), while unsaturated fatty acids are liquid at room temperature. 
In organic chemistry, saturated fats are described as:
- Short-chain fatty acids (SCFAs): contain two to four carbon atoms
- Medium-chain fatty acids (MCFAs): contain 6 to 12 carbon atoms
- Long-chain fatty acids (LCFAs): contain 14 to 24 carbon atoms
Most of the saturated fatty acids in coconut oil are medium-chain fatty acids, but it is also a source of LCFAs and SCFAs. 
- Lauric acid (45-52%)
- Myristic acid (16-21%)
- Palmitic acid (7%-10%)
- Caprylic acid (5%-10%)
- Capric acid (4%-8%)
- Stearic acid (2%-4%)
- Caproic acid (0.5%-1%)
- Palmitoleic acid (trace amounts)
- Oleic acid (5%-8%)
- Linoleic acid (1%-3%)
- Linolenic acid (up to 0.2%)
Coconut Oil for Horses
Coconut oil is suitable for feeding horses and offers unique benefits compared to other fat sources in the equine diet.
Fat is efficiently absorbed and, unlike grains and sweet feeds, it does not pose the same risk of digestive issues and metabolic dysfunction. Replacing grains with fat can also reduce tying-up episodes in susceptible horses. 
Most equine diets contain less than 8% fat. However, horses in heavy exercise programs can be fed up to 20% or more of their digestible energy requirement from fat. 
Coconut Oil as a Fat Supplement
All oils and pure fats provide the same amount of caloric energy per gram. However, not all oils are equal in terms of how they influence processes in the body.
Coconut oil is unique because of its high saturated fat content. While there is limited research on the effects of feeding coconut oil to horses, there have been studies on equine diets containing saturated fatty acids.
One study showed no adverse effects of feeding horses a fat-supplemented diet for 16 months. There were also no apparent disadvantages of providing a vegetable oil with predominantly saturated fat versus an oil with unsaturated fat. 
Coconut oil is also more stable than other vegetable oils and has a longer shelf-life.
Oils that contain primarily polyunsaturated fatty acids are prone to rancidity. However, saturated fats in coconut oil are less reactive with oxygen and will not oxidize as quickly.
In the liver, medium-chain fatty acids are either converted into triglycerides (a storage form of fats) or used as a source of energy to fuel metabolic processes. 
Because MCTs are absorbed and digested more rapidly than long-chain fatty acids, they are preferentially burned for energy instead of being stored as body fat. 
However, they can also be stored as body fat if excess amounts are consumed.
Benefits of Coconut Oil for Horses
More research is needed to understand all of the health benefits of coconut oil for horses. However, some benefits of feeding coconut oil include:
1) Source of Cool Calories
Cool calories are energy sources that do not make your horse “hot”.
Adding coconut oil to your horse’s diet is one way to increase calorie supply without relying on grains or commercial feeds.
These products are often high in non-structural carbohydrates (sugars and starches), which can increase blood sugar and cause gut disturbances.
Weight Gain Without Sugar or Starch
Horses that need to gain weight are often fed high amounts of grain-based concentrates or sweet feeds flavoured with molasses.
Coconut oil is a calorie-dense additive that can help horses gain weight without having to feed excess sugar or starch.
Metabolic Dysfunction and Laminitis
Coconut oil is a good option for horses with metabolic conditions who require a low sugar and stach diet.
Oils provide calories without increasing blood glucose or raising insulin levels. 
High intake of starch and sugar can disrupt the hindgut microbiome which increases the risk of laminitis. Horses that are adapted to added oil in the diet maintain hindgut function and are not at risk of laminitis from this energy source.
Reducing Heat from Digestion
The digestion of fats generates less heat than protein and carbohydrate digestion. Because of this, fat supplements such as coconut oil are ideal for performance horses and horses in hot climates.
Reducing the Risk of Tying Up
As a source of cool calories, coconut oil may benefit horses prone to tying up. High-starch diets contribute to a high frequency of tying-