Shun NagaiIn the field of pet nutrition, many studies have described the benefits of medium-chain triglycerides (MCTs) for supporting cognitive function. In particular, MCTs are said to be effective for aging, cognitive dysfunction syndrome (CDS), and epilepsy.
However, the benefits of MCTs are not limited to cognitive support alone. Although this is still an emerging area of research, dietary intake of medium-chain fatty acids is also expected to help support digestive and cardiac health.
What Are Medium-Chain Triglycerides (MCTs)?
Medium-chain triglycerides (MCTs) are lipids composed of fatty acids with 6 to 12 carbon atoms. They are commonly found in tropical oils such as palm kernel oil and coconut oil. These oils contain medium-chain fatty acids such as caproic acid, caprylic acid, capric acid, and lauric acid.
The Difference Between Long-Chain and Medium-Chain Fatty Acids
One of the major differences between long-chain triglycerides (LCTs) and medium-chain triglycerides (MCTs) lies in how they are digested and absorbed in the body.
Long-chain fatty acids are broken down by digestive enzymes, mainly lipase secreted from the pancreas, and are ultimately converted into fatty acids and glycerol. During this process, bile acids and digestive enzymes help form small particles called micelles, which are then absorbed, transported through the bloodstream, and eventually delivered to the liver.
MCTs, on the other hand, are digested differently. They are easier to digest, do not require the same degree of pancreatic enzyme involvement, and are absorbed more directly into the bloodstream before being transported to the liver. As a result, MCTs are readily digested and quickly used as an energy source, making them less likely to be stored as body fat. This makes MCTs an especially efficient energy source for aging animals.
Comparison of LCTs and MCTs
| Item | LCTs (Long-Chain Triglycerides) | MCTs (Medium-Chain Triglycerides) |
|---|---|---|
| Carbon chain length | Long-chain fatty acids | 6–12 carbon atoms |
| Digestion | Requires pancreatic lipase and bile acids | Easier to digest and absorb |
| Absorption route | Absorbed via micelles and transported through normal lipid pathways | More directly absorbed into the bloodstream and transported to the liver |
| Speed of energy use | Slower | Rapid |
| Likelihood of fat storage | Higher | Lower |
| Suitability for senior animals | Less efficient as a rapid energy source | Particularly useful as an efficient energy source |
Improvements in Epilepsy and Cognitive Function
MCTs have attracted considerable attention as a highly beneficial nutrient for aging, cognitive support, and epilepsy management. In dogs with epilepsy, many studies have confirmed that MCTs can reduce both seizure frequency and the number of days on which seizures occur. Diets rich in MCTs have also been shown to positively affect behavior and cognitive function in epileptic dogs.
Furthermore, MCTs have been found to have positive effects on cognitive function in senior dogs. They provide energy to the brain and play an important role in maintaining brain health, especially in older dogs. Diets containing MCTs have also been shown to support learning ability and improve behavior. In this way, MCTs may help prevent age-related cognitive decline and contribute to preserving cognitive function.
In addition, MCTs may have broader benefits for overall canine health, and because of these multiple effects, they are receiving increasing attention as a nutritional tool for supporting dogs’ well-being.
Digestive Health
MCTs are also known to have beneficial effects on intestinal health. They may help suppress intestinal inflammation and appear less likely than long-chain fatty acids to promote inflammatory responses.
For this reason, MCTs are believed to help reduce intestinal inflammation in dogs. They may be particularly useful for dogs with digestive disorders, such as those with impaired fat absorption. Because MCTs are easy to digest and are rapidly converted into energy, they may also help support gastrointestinal function.
In addition, MCT-based diets may benefit dogs with insufficient bile acids by helping improve fat utilization. MCTs may also increase beneficial gut bacteria while suppressing the growth of harmful bacteria, thereby improving the intestinal environment. This may help maintain gut health, strengthen immune function, and reduce oxidative stress.
Supplementing MCTs may therefore help reinforce the gut environment, promote digestive health, and potentially contribute to the improvement of metabolic disorders. They may also help prevent or improve intestinal inflammation.
Heart Health
MCTs may also have therapeutic potential in myxomatous mitral valve disease (MMVD), a relatively common heart disease in dogs.
A 2012 study showed that dogs fed a diet containing MCTs had reduced cardiac enlargement and lower blood pressure. MCTs have also been shown to improve metabolism and reduce inflammation and oxidative stress, which may help lessen the burden on the heart.
In addition, diets containing MCTs may help delay the onset of heart disease and support energy metabolism. Studies involving dogs with congestive heart failure have also confirmed that MCTs can positively affect fat metabolism.
MCT-rich diets may be especially beneficial for dogs with impaired mitochondrial function, as mitochondria are responsible for converting sugars and fats into energy using oxygen. In such dogs, MCTs may help improve energy metabolism.
That said, several issues remain before the effects of MCTs can be fully understood. For example, some studies have examined only specific breeds or included other supplements, making it difficult to determine whether the observed benefits were due solely to MCTs.
In addition, in dogs with pancreatic problems, diets containing MCTs have been shown to increase blood cholesterol and vitamin levels, but the exact effect of elevated cholesterol on heart health is not yet fully understood.
Other Effects: Muscle, Obesity, and Nutrition
For dogs suffering from DMVD (degenerative mitral valve disease / mitral valve insufficiency), MCTs may help support or improve muscle mass. This effect is thought to be related to changes in genes involved in muscle function.
MCTs are also relevant to obesity management. They may help the heart use fatty acids more efficiently and increase substances involved in the energy-producing process known as the citric acid cycle. By promoting greater ketone production, MCTs may provide energy more efficiently than long-chain fatty acids.
In addition, one study found that even when MCTs accounted for up to 11% of the total diet in dog food, they had no major effect on palatability, cholesterol, protein digestibility, or mineral absorption. This suggests that adding MCTs to dog food may not adversely affect the key nutritional elements necessary for canine health.
Effects and Potential of MCTs in Cats
Research on the effects of MCTs in cats is still limited, but some interesting findings have been reported. One study showed that adding MCTs to a cat’s diet did not lead to food refusal and did not negatively affect fat metabolism.
This suggests that MCTs may also have positive effects in healthy cats and in cats with metabolic issues. However, another study found that cats were less willing to consume diets higher in MCTs. Because the findings are still inconsistent, it remains unclear how MCTs affect cognitive function in cats.
By contrast, MCTs are already known to help dogs with epilepsy and may also be useful in improving age-related cognitive decline. They are also believed to have positive effects on the heart and may contribute to the improvement of cardiovascular disease.
Research in this area is progressing, and MCTs are expected to offer a variety of benefits not only for dogs but potentially for cats as well. However, further studies are still needed.