Medium-chain triglycerides are triglycerides whose fatty acids have an aliphatic tail of 6–12 carbon atoms. The fatty acids found in MCTs are called medium-chain fatty acids. Wikipedia
So, there are lots and lots of explanations about why and how MCT helps you and your brain. But the only proof that you need is the proof you will find yourself by using it. The easiest thing to do is to pour it into your coffee, tea or smoothie in the morning and see how you feel. I started with a tablespoon in my coffee and then increased as I got used to the dose and the effect.
It has no taste or smell so you can add it to virtually anything. You can cook with it too. It is basically super concentrated coconut oil, but it tastes like nothing. If you are trying for ketosis or the fat burning phase of a low carb ketogenic diet this will also help put you there and keep you there for longer periods which I believe will help lead to weight loss.
What does it do? It gives me an instant boost in the morning and clarity in my brain. I feel like I can think better and function at a high level for hours without breakfast as the fat acts like fuel and food. When coupled with caffeine the drink gives me a nice steady level of energy, less to no sugar cravings and no feeling of a crash before lunch when I am actually hungry and ready to eat.
All I suggest here is that you try it for yourself. This is a routine that I have stuck to for years and beyond brushing my teeth I can’t really say I have stuck with anything as loyally as the MCT supplement.