MCT oil (medium-chain triglyceride oil) is one of the most widely used supplements on the ketogenic diet. Derived primarily from coconut oil, MCTs are a unique type of saturated fat that’s rapidly absorbed and converted directly into ketones by the liver — making them a powerful tool for enhancing ketosis and energy levels.
Medium-chain triglycerides are fatty acids with a chain length of 6-12 carbons. The most important types for keto are: C8 (caprylic acid) — the most ketogenic, converted to BHB fastest; C10 (capric acid) — also highly ketogenic; and C12 (lauric acid) — behaves more like a long-chain fatty acid. Pure C8 MCT oil provides the most potent ketogenic effect.
MCT oil offers several advantages for keto dieters: rapid elevation of blood ketones, increased mental energy and focus, appetite suppression, support during the keto adaptation phase, and convenient fat intake for hitting macro targets. Many keto practitioners add MCT oil to their morning coffee (known as “bulletproof coffee”).
Start with just 1 teaspoon (5ml) per day and increase gradually over 1-2 weeks to 1-3 tablespoons. Starting with too much too quickly causes digestive distress (loose stools). Always take MCT oil with food until your digestive system adapts.
Available from Holland & Barrett, Amazon UK and specialist health stores. Look for C8/C10 blends or pure C8 products. Avoid products containing significant C12 (lauric acid) fractions. Check our keto beverage recipes for ways to incorporate MCT oil, and browse our keto snack recipes for MCT-boosted snacking ideas.