What are MCTs?
Medium chain triglycerides appear to boost metabolism, suppress appetite, and reduce fat stores. Can MCTs help you lose weight?
Sponsor: Audible.com, the Internet’s leading provider of audiobooks with more than 100,000 downloadable titles across all types of literature, including fiction, non-fiction and periodicals. For a free audiobook of your choice, go to audiblepodcast.com/diva.
Several https://nutritiondiva.quickanddirtytips.com/ fans have asked me to dedicate an episode to MCTs, or medium chain triglycerides. MCTs have long been used as a nutrition therapy for certain medical conditions, but lately there’s been a lot of interest in MCTs as a weight loss supplement. Before you start popping pills, let’s take a look at the research.
What Are MCTs?
Triglyceride is just a fancy word for fat, and fat molecules come in a variety of sizes, or chain lengths. Most dietary fats (and virtually all unsaturated fats) are long chain triglycerides, with more than 12 carbon /education/science/what-are-atoms in their molecular skeleton. But some saturated fats are shorter. Fats with 6 to 10 carbon atoms in their skeleton are referred to as medium chain triglycerides, or MCTs. Fats with fewer than 6 carbon atoms are short chain triglycerides.
What Do MCTs Do?
Because of their shorter chain length, MCTs sort of jump to the head of the line and are absorbed and metabolized more quickly than longer chain fats. They’re frequently used in medical nutrition formulas for people who, for whatever reason, can’t digest and absorb fats. They’re also added to baby formula to make it more closely resemble human /health-fitness/prevention/what-are-the-benefits-of-breastfeeding.
Beyond these medical uses, research suggests that MCTs have special properties—like increasing metabolism or reducing appetite—that could make them a powerful tool in the fight against obesity. But before we get too excited, let’s take a closer look at the details.
MCTs increase metabolism. Studies ofboth animals and humans show that increasing the amount of MCT in the diet causes the body to burn more energy, or calories. The effect seems to https://www.ncbi.nlm.nih.gov/pubmed/2021124, which is certainly helpful. On the other hand, women seem to get far less of a metabolic boost from MCTs than men, which just seems sort of unfair. Either way, however, the effect seems to https://www.ncbi.nlm.nih.gov/pubmed/10232626, which makes it of somewhat limited usefulness as a tool for long-term weight management.
MCTs decrease food consumption. Studies in rats show that when you load them up with MCTs, they eat less and gain less weight. So far, so good. Studies in humans have been less encouraging. At least one study found https://www.ncbi.nlm.nih.gov/pubmed/8696422, but these folks were being fed a high-calorie, high-fat diet—with 2/3 of the calories coming from fat. The study diet was deliberately designed to result in weight gain—not the sort of thing we want to replicate in the real world. Moreover, a more recent study using a less extreme diet found that subbing in MCTs for longer chain fatty acids https://www.ncbi.nlm.nih.gov/pubmed/20451538 in how much the subjects ate, either at that meal or the next one.
MCTs reduce fat stores. There’s one more tantalizing piece of evidence to consider. Some https://www.ncbi.nlm.nih.gov/pubmed/24679 have found that lab rats that were fed MCTs instead of longer chain fats ended up with smaller fat cells and fewer of them. That certainly sounds good. Unfortunately, https://www.ncbi.nlm.nih.gov/pubmed/8387971 failed to duplicate that result. Interestingly, in the later study, diets high in fish oil were more effective than diets high in MCT in reducing fat stores.
Can MCTs Help You Lose Weight?
OK, enough with all the . After all, life is not lived in the lab. So, how might all of this translate into the real world? Can adding MCTs to your diet have a beneficial effect on your body weight or composition? Research in humans has been pretty disappointing so far. Some studies have found that dieters who substituted MCTs for other fats in a calorie-controlled environment https://www.ncbi.nlm.nih.gov/pubmed/19156155. Others https://www.ncbi.nlm.nih.gov/pubmed/12532160 with MCTs.
How to Increase Your Intake of MCTs
Let’s also consider the practicalities. The most promising studies involved diets that were very high in fat, with the majority of the fat coming from MCTs. The richest natural food source of MCTs is /health-fitness/healthy-eating/what-are-the-benefits-of-coconut-oil, which is about 2/3 MCTs. It’s also virtually 100% saturated fat. To emulate these experimental diets in the real world, you’d have to use coconut oil—and plenty of it—as your only source of fat. That seems a little extreme to me. (And all that saturated fat would give the folks over at American Heart Association…well…a /health-fitness/mens-health/what-causes-a-heart-attack.)
You can also buy pure MCT oil at the health food store, which is produced by artificially separating the MCTs out of coconut or palm kernel oil. Not only is it expensive but, in my experience, extracting certain nutrients or compounds out of whole foods never seems to work out as well as we hope. Maybe there’s a reason that whole foods almost always contain fatty acids in a variety of chain lengths.
The Bottom Line on MCTs
Dramatically increasing the proportion of MCTs in your diet might help you burn a few extra calories and might (or might not) be a hedge against weight gain—especially if you’re a guy. It could also have some downsides. High intake of MCTs has been in some individuals. They can also cause stomach upset and digestive distress, especially if you increase them suddenly.
If you include dairy, coconut, or palm kernel oil in your diet, then your diet already contains some medium chain triglycerides. Woo-hoo! Meanwhile, you get other benefits from other sources of fat, such as /health-fitness/healthy-eating/when-to-use-olive-oil, /health-fitness/healthy-eating/should-you-be-worried-about-mercury-in-fish, /health-fitness/healthy-eating/what-s-the-difference-between-california-and-florida-avocados, and /health-fitness/healthy-eating/nutty-nutrition-tips—benefits you’d be missing out on if you replaced those fats with more MCTs. I think this is another case where a /health-fitness/healthy-eating/how-important-is-a-varied-diet is probably the best of all worlds.
Coconut Oil image courtesy of Shutterstock
About the Author
Monica Reinagel is a board-certified licensed nutritionist, author, and the creator of one of iTunes’ most highly ranked health and fitness podcasts. Her advice is regularly featured on the TODAY show, Dr. Oz, NPR, and in the nation’s leading newspapers, magazines, and websites. Do you have a nutrition question? Call the Nutrition Diva listener line at 443-961-6206. Your question could be featured on the show.
