Ketones and your brain

Our brains have a dual fuel mechanism. The brains of large brained animals like us can run on either glucose or ketones, derived from fat. If given the choice they prefer ketones. The rise in popularity in high fat ketogenic diets is partly to do with the ability of ketones to nourish and improve brain function when things go wrong, as well as weight loss benefits and the potential to reverse diabetes.

Epilepsy, for example, has been successfully treated in both children and adults with a high fat ketogenic diet since the 1920’s often halving frequency of fits. A recent study on people with Parkinson’s found that those placed on a high fat diet had 41 per cent reduction in shaking, compared to 11 per cent on a low fat diet. There’s also a potential benefit in chronic fatigue syndrome.

The reason these high fat keto diets work is that if a cell’s sugar metabolism is all messed up, a consequence of insulin resistance promoted by a high sugar diet, then the cell struggles to get enough energy and you feel mentally and physically tired. But if, like a hybrid car, you can switch to a different fuel, ketones, then the cell comes back to life. This is especially true in struggling brain cells. When you fast, and switch to burning your body fat, the brain derives two thirds of its energy from ketones.

What are ketones made from and how can you make them?

Ketones are made from medium-chain triglycerides, known as MCTs. There’s been a rise in sales of MCT oil, which can be derived from palm or coconut oil. Also gaining in popularity are ketone salts and pure synthetic ketones, although these are yet to clear EU Novel Foods so are not yet available in Europe.

Fats are chains of carbon molecules and MCTs contain C6, C8, C10 and C12 oil. Of these C8 oil (called tricaprylin or caprylic acid triglyceride) makes ketones fastest. While coconut oil is 60 per cent MCTs only12 per cent of MCTs is C8. That means that only 7 per cent of coconut oil is C8.

The growth in bullet-proof coffee, adding a blob of coconut oil to your morning brew, is one way to up ketone levels but it’s much less effective than adding pure C8 oil. I start my day with a Hybrid Latté – a coffee with carb-free almond milk, almond butter, C8 oil, cacao and cinnamon. While coffee gives you energy like a bank loan gives you wealth it does speed up conversion to running on ketones.

Case studies with coconut oil have shown short-term beneficial effects in people with Alzheimer’s, with improved mental clarity. A study last month gave 52 people with pre-dementia either two tablespoons (30g) of C8 oil or a placebo and measured changes in their cognitive function. Brain ketone metabolism increased by 230% indicating that their brain cells were switching to using ketones as fuel, and the more this was happening the more cognitive improvements occurred. The authors suggested than three tablespoons (45g) of C8 oil might be better.

Are there downsides?

Are there any downsides? Unlike other fats, C8 oil doesn’t need to be digested and goes straight to the liver, which turns it into ketones. Some people report abdominal or stomach discomfort. This can be minimized by building up slowly – starting with a teaspoon, then a dessertspoon, then a tablespoon, then two, then three tablespoons taken at different times of day, with food or in drinks or neat.

If glucose is petrol- ketones are electricity

If glucose is petrol – ketones are electricity. If your brain needs a service, switching from running on carbs to running on ketones by eating a low carb, high fat diet for a week, may be a good idea. It takes only 12 hours to start to run out of glucose fuel and start switching to ketones. I do an 18 hour carb fast most days – dinner at pm, lunch at 1pm, and a Hybrid Latté using Ketofast in the morning. My brain stays sharp and I don’t feel hungry.

More Information

For more info read The Hybrid Diet by Patrick Holford and Jerome Burne (Piatkus) and The 5 Day Diet.


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