"Coconut oil is unusually rich in short and medium chain fatty acids. Shorter chain length allows fatty acids to be metabolized without use of the carnitine transport system. Mildronate, which I discussed in an article on adaptogens, protects cells against stress partly by opposing the action of carnitine, and comparative studies showed that added carnitine had the opposite effect, promoting the oxidation of unsaturated fats during stress, and increasing oxidative damage to cells. I suspect that a degree of saturation of the oxidative apparatus by short-chain fatty acids has a similar effect--that is, that these very soluble and mobile short-chain saturated fats have priority for oxidation, because they don't require carnitine transport into the mitochondrion, and that this will tend to inhibit oxidation of the unstable, peroxidizable unsaturated fatty acids." - Ray Peat[1]
The short and medium chain fatty acids can be digested much more quickly than the more common long chain fatty acids found in foods, and can be used directly by your mitochondria for energy without having to be broken down first; coconut oil can very quickly increase your metabolism.
"There are many directly anti-thyroid substances, but the only directly thyroid-activating substances I know of are coconut oil, progesterone, and pregnenolone."[2] - Ray Peat
The short, stable fatty acids in coconut oil can disrupt the membranes of bacteria, killing them directly while supporting the body's energy production.