MCT oil is not clearly harmful to your heart, but it’s not heart-protective either. A large meta-analysis published in The Journal of Nutrition found that MCT oil does not raise LDL cholesterol, total cholesterol, or HDL cholesterol. It does, however, cause a small increase in triglycerides, another blood fat linked to cardiovascular risk. That increase was modest enough that researchers deemed it “unlikely to be clinically meaningful on an individual level.”
What MCT Oil Does to Your Cholesterol
The biggest worry people have about MCT oil is whether it raises LDL cholesterol, the type most strongly linked to heart disease. The evidence is reassuring on that front. A systematic review and meta-analysis of randomized trials found MCT oil had essentially no effect on LDL (a change of just 0.02 mmol/L, which is statistically insignificant). Total cholesterol and HDL cholesterol were similarly unchanged.
This makes MCT oil quite different from coconut oil, which is often confused with it. The American Heart Association reviewed seven controlled trials comparing coconut oil to unsaturated oils and found that coconut oil raised LDL cholesterol in all seven, significantly in six. The AHA explicitly advises against using coconut oil for this reason. MCT oil is extracted and refined from coconut or palm kernel oil, but it contains a different mix of fatty acids, which is why the two products behave differently in your body.
The Triglyceride Question
Where MCT oil does leave a mark is on triglycerides. The same meta-analysis found an average increase of 0.14 mmol/L in fasting triglyceride levels. Elevated triglycerides are an independent risk factor for heart disease, stroke, and pancreatitis, so this isn’t something to dismiss entirely.
The likely explanation is how your body processes MCTs. Unlike the long-chain fats in most foods, medium-chain fats are absorbed quickly through the gut and travel straight to the liver through the portal vein. Once there, they’re rapidly burned for energy. But when the liver receives more than it can immediately use, it converts the excess into new fat molecules and packages them as triglycerides for release into the bloodstream. This process, called de novo lipogenesis, is what nudges triglyceride levels upward.
Still, the size of the increase matters. A bump of 0.14 mmol/L is small. For context, triglyceride levels below 1.7 mmol/L (150 mg/dL) are considered normal, and the increase from MCT oil represents a fraction of that threshold. For someone with already healthy triglycerides, this shift is unlikely to push them into a concerning range.
Who Should Be More Cautious
If you already have elevated triglycerides, heart disease, or fatty liver disease, MCT oil deserves more scrutiny. Cleveland Clinic dietitians note that MCT oil is generally safe in small doses for healthy people but recommend against it for those living with heart or liver conditions, precisely because MCTs are still fats that the liver must process. Adding extra fat to an already burdened liver can worsen lipid imbalances.
Animal research reinforces this concern. When the liver’s ability to burn medium-chain fats is impaired, fat and cholesterol accumulate in liver tissue. The genes responsible for breaking down fat become less active while genes involved in creating new fat ramp up. This isn’t a direct parallel to a healthy human taking a tablespoon of MCT oil, but it illustrates why liver health matters in this equation.
MCT Oil Compared to Other Fats
MCT oil occupies an awkward middle ground. It doesn’t raise LDL like coconut oil or butter, but it doesn’t improve cardiovascular markers the way unsaturated fats do. Olive oil, for instance, has decades of evidence showing it lowers LDL, reduces inflammation, and is associated with fewer heart attacks and strokes. If your goal is specifically heart health, olive oil and other liquid plant oils are a stronger choice.
The AHA’s longstanding recommendation, reaffirmed in its 2017 presidential advisory, is to reduce saturated fat intake and replace it with unsaturated fats, particularly polyunsaturated fats. MCT oil is a saturated fat. While it doesn’t carry the same LDL penalty as butter or coconut oil, it also doesn’t offer the protective benefits of swapping in unsaturated alternatives. Using MCT oil in place of olive oil in a salad dressing, for example, means trading a heart-protective fat for a neutral one.
How Much Is Reasonable
Clinical trials have used doses ranging from about 15 grams per day (roughly one tablespoon) up to higher amounts without reporting cardiovascular side effects in healthy participants. A study in acute stroke patients found that 15 grams per day for four days had no adverse effects and appeared to reduce inflammation markers. Most nutrition experts suggest keeping intake modest, in the range of one to two tablespoons daily, and treating MCT oil as a supplement rather than a primary cooking fat.
Digestive side effects like cramping, nausea, and diarrhea tend to be the limiting factor before cardiovascular concerns become relevant. Starting with a teaspoon and working up gives your gut time to adjust.
The Bottom Line on Heart Risk
MCT oil is not bad for your heart in the way that trans fats or excessive saturated fat from dairy and meat can be. It leaves LDL cholesterol untouched and causes only a small, likely inconsequential rise in triglycerides for most people. But “not harmful” isn’t the same as “beneficial.” The health halo around MCT oil, largely driven by its popularity in keto and biohacking circles, outpaces the actual evidence. If you enjoy using it in coffee or smoothies and your lipid levels are healthy, moderate amounts are unlikely to cause problems. If you have existing heart disease or high triglycerides, other fats are a safer bet.