Don't Confuse Coconut Oil with MCT Oil
Coconut oil is the darling of the keto dieters, as they often use it to provide energy to their carb-starved bodies and to facilitate their mystical transition into ketosis... or so they think.
Many keto dieters are under the impression that coconut oil is synonymous or virtually synonymous with the fatty acids known as medium chain triglycerides, or MCTs.
MCTs are cool because, unlike long-chain triglycerides (LCT), they skip an important biochemical step and are directly transported into the portal vein and shuttled to the liver, where they quickly provide energy.
MCTs also enter mitochondria independently and are converted to two ketone bodies that are then further metabolized to produce CO2, water, and energy instead of being deposited as fat. That's huge.
Contrast that with LCTs. They combine with proteins to form chylomicrons that enter blood through the lymphatic system and mostly bypass the liver. Unfortunately, as these lipoproteins circulate round and round the body, they deposit fatty acids to tissues, thereby contributing to your porkiness. To make matters worse, some of these fatty acids are troweled onto artery walls.
Here's Where It Gets Tricky
Coconut oil contains three fatty acids that are usually considered to be MCTs: caprylic acid, capric acid, and the most abundant and mythologized one, lauric acid.
Depending on who you talk to, between 15% and 55% of the oils in coconut oil are MCTs, but let's be generous and assume that number is 50%. Great, but lauric acid, the predominant "MCT" in coconut oil, is metabolized more like a long-chain fatty acid, thus throwing the MCT magic of coconut oil into question.
Between 70 and 75% of lauric acid is absorbed and transported by the same chylomicrons that are associated with LCTs and run around the body slapping fatty acids against your blood vessel walls and fat cells.
That means that if you're lucky, only about a third of the fatty acids in coconut oil are absorbed like MCTs and wouldn't be stored as fat or muck up your cardiovascular system.
None of the research on the alleged benefits of MCTs can be applied to coconut oil because it's made up of a variety of short-chain, medium-chain, and long-chain fatty acids.