We’ve all heard the saying ‘Food is Fuel’. Not all foods are equal as fuels. It takes a little more thought and exploration to work which fuels are best; you have to make sure you put petrol in your petrol car, rather than diesel, and it is the same for your body. In this ketosis series, we’re going to be discussing the different types of fuel that our bodies use to operate; which fuel source is the most efficient; and how we can induce, maintain, and identify the different energy states within our bodies, and what the benefits are of each.
We can induce ketosis via our diet, called nutritional ketosis, by eating a very high-fat, very low-carbohydrate, moderate-protein diet. This puts our bodies into fat burning mode; the resultant effects including weight loss and enhanced mental and physical performance.
The cells of your body can run from sugars (from carbohydrates) or ketone bodies (from fats). Throughout our evolutionary history, we ate a fat-based, ketogenic diet; a diet that promotes our bodies to run from fats as the primary fuel source, rather than carbohydrates. Ketosis can be a transient state, or can be sustained for long periods of time i.e. weeks or months.1 In the modern day, as a result of cooking and food processing techniques, the predominant fuel that is powering people’s bodies is sugar. Cereal, porridge, or toast for breakfast; sandwiches, grains, pulses, and potatoes common in lunches and dinner; and all often accompanied by sugary drinks. Regardless of whether we should include carbohydrates in our diets, we eat WAY too many!
“There are essential amino acids and essential fatty acids, but there is no such thing as an essential carbohydrate”. Richard K Bernstein, M.D1
Carbohydrate rant over, back to ketosis!
Our bodies switch to using ketones as fuel in a state of starvation – not having eaten – to conserve the precious stores of glucose. This clever switch provides a very efficient fuel for the brain and prevents the breakdown of muscles for the formation of glucose; if the body needs to, it can convert muscles, which are made from protein, into glucose via a process called gluconeogenesis.
The ketogenic diet is the standard of treatment for drug-resistant epilepsy, and is used to control seizures. As the early epilepsy researchers found, the ketogenic diet mimics the metabolic and physiological benefits of fasting.2 This is mediated by carbohydrate restriction: low glucose, low insulin, and high ketone bodies. The ketogenic diet lowers insulin, which triggers a lot of physiological processes, including ketogenesis, which is neuroprotective.2, 3
There are two types of ketosis. Nutritional ketosis is induced as a result of prolonged carbohydrate restriction, and can mimic many of the metabolic states of fasting; this can be maintained indefinitely, unlike fasting. Starvation-induced ketosis is induced if we stop eating or severely limit carbohydrate intake. Our body mobilises fat stores for energy from dietary fat or our adipose tissues, which are our fat stores. These are metabolised (broken down) in the liver and converted to the ketone bodies, beta-hydroxybutyrate and aceto-acetate. These ketone bodies are alternative energy sources that are more efficient than sugars. As your brain becomes adapted to ketones, your thinking and physiological processes are maintained and enhanced.
Let’s think of our metabolism as a fire that burns to keep us going. There’s only so much wood we can fit into the fire at any time, so we need to choose the most efficient fuel that can keep us going the longest. Eating sugar, or sugary foods, is akin to putting kindling on the fire; it will burn brightly, but for a brief time.
- Starchy foods (rice, beans, grains) are like twigs.
- Potatoes, pasta, and cereal are like crumpled paper.
- Alcohol and sweetened drinks are like petrol.
Fats (ketones), on the other hand, are like the logs; they take a while to get going, but once they’re burning they will do so intensely, and for a long time. You can real feel this once you’ve spent some time taking yourself in and out of ketosis and seeing the effects it has on your energy levels! Appetite suppressive effects and removal of sugar cravings means it becomes easy to fast for long periods at a time, the mental clarity is liberating and the weight-loss an added bonus (if that’s what you need). Furthermore, you can build muscle on ketosis! The protein sparing effects mean the weight loss is not mediated by muscle wasting, and the proportions of the diet mean you can eat meaningful amounts of protein to gain muscle. Think better, eat less, lose fat, and gain muscle. What’s not to love?
What Are the Benefits of Ketosis?
- Natural hunger and appetite control.
- Effortless weight loss and maintenance.
- Mental clarity
- Sounder, more restful sleep
- Normalized metabolic function
- Stabilized blood sugar and restored insulin sensitivity.
- Lower inflammation levels
- Lowered blood pressure
- Increased HDL (good) cholesterol
- Reduced triglycerides
- Lowered or eliminated small LDL particles (bad cholesterol).
- Ability to go twelve to twenty-four hours between meals.
- Use of stored body fat as a fuel source.
- Better fertility
- Prevention of traumatic brain injury.
- Increased sex drive
- Improved immune system
- Slowed aging due to reduction in free radical production.
- Improvements in blood chemistry.
How Do You Induce Ketosis?
We can induce ketosis via our diet, called nutritional ketosis, by eating a very high-fat, very low-carbohydrate, moderate-protein diet. This puts our bodies into fat burning mode; the resultant effects including weight loss and enhanced mental and physical performance. Nutritional ketosis can take 24-48 hours to induce, but with ketone-forming supplementation, for example the medium chain triglyceride (MCT) oils added to buttery coffee, ketosis can be achieved in 10-15 minutes. Starvation-level ketosis, which would take a week to achieve nutritionally, can be achieved in 10 minutes with the most potent form of ketone supplements, ketone esters.
Jimmy Moore, author of the book Keto Clarity, has a helpful way of remembering the ground rules:
Keep carbs low.
Eat more fat.
Test ketones often.
Overdoing protein is bad.4
MCT oil: the golden boy of ketosis!
MCT’s are saturated fats, whose medium chain length allows them to be absorbed by your body and used almost completely as energy, by being converted into ketone bodies. This means that they are not stored as fat, unlike other fats sources.5 When switching to a ketogenic diet, adding MCT oil to your coffee, tea, and food can rapidly decrease the time it takes your body to become fat adapted, and the time it takes you to enter ketosis. Be careful though! Start with a small amount (1 tbsp in one sitting) and work your way up – too much too quickly can result as something people refer to as disaster pants! If the MCT oil is taken with a meal, with protein and fibre, to slow down gastric transit time and gastric emptying, it can be tolerated better.
It takes a couple of weeks to become ‘fat-adapted’; that is, to upregulate the expression of genes involved with fat metabolism. In other words for your body to sense that you are eating more fat, to read the machine-building blueprints in your DNA, and to build the machines that are used to digest, process and convert the fats you eat into ketones, which are then burned as fuel.
If you’re looking for the next step in your dietary experimentation then ketosis is the way forward – or if you’re looking for more energy, to lose weight, have better performance stamina, or improve your cognition. It’s almost hard to believe that something so simple as a specifically organised diet can have so many benefits, with no downsides (well, maybe the mild ketosis breath!), but with a little more thought it makes sense. Our ancestors evolved with a ketogenic diet, and we are born in ketosis. Maybe it works so well because that’s how our bodies are evolutionary meant to operate? Stay tuned for Part 2.
- Attia, P. (n.d.). Ketosis – advantaged or misunderstood state? (Part I). In The Eating Academy: The Personal Blog of Peter Attia. Retrieved from http://eatingacademy.com/nutrition/ketosis-advantaged-or-misunderstood-state-part-i
- Attia, P. (n.d.). Ketosis – advantaged or misunderstood state? (Part II). In The Eating Academy: The Personal Blog of Peter Attia. Retrieved from http://eatingacademy.com/nutrition/ketosis-advantaged-or-misunderstood-state-part-ii
- Williams, C. (n.d.). The Origin (and future) of the Ketogenic Diet – Part 1. In Robb Wolf. Retrieved from http://robbwolf.com/2015/09/24/the-origin-and-future-of-the-ketogenic-diet-part-1/
- Williams, C. (n.d.). The Origin (and future) of the Ketogenic Diet – Part 2. In Robb Wolf. Retrieved from http://robbwolf.com/2015/09/30/the-origin-and-future-of-the-ketogenic-diet-part-2
- Williams, C. (n.d.). The Origin (and future) of the Ketogenic Diet – Part 3. In Robb Wolf. Retrieved from http://robbwolf.com/2015/10/07/the-origin-and-future-of-the-ketogenic-diet-part-3/
- Gedgaudas, N., & Kharrazian, D. (2014). RETHINKING FATIGUE: What Your Adrenals Are Really Telling You And What You Can Do About It. (s.l): Primal Body Primal Mind Publishing.
- Neal, E. G., Chaffe, H., Schwartz, R. H., Lawson, M. S., Edwards, N., Fitzsimmons, G., Cross, J. H. (2008). The ketogenic diet for the treatment of childhood epilepsy: a randomised controlled trial. Lancet Neurology, 7(6), 500–506.
- Vining, E. P., Freeman, J. M., Ballaban-Gil, K., Camfield, C. S., Camfield, P. R., Holmes, G. L., Wheless, J. W. (1998). A multicenter study of the efficacy of the ketogenic diet. Archives of Neurology, 55(11), 1433–1437.
- Moore, J., & Westman, E. (2014). Keto Clarity: Your Definitive Guide to the Benefits of a Low-Carb, High-Fat Diet. New Jersey, USA: Victory Belt Publishing.
- Freedman, B. I., Langefeld, C. D., Murea, M., Ma, L., Otvos, J. D., Turner, J., … Parks, J. S. (2011). Apolipoprotein L1 nephropathy risk variants associate with HDL subfraction concentration in African Americans. Nephrology, Dialysis, Transplantation: Official Publication of the European Dialysis and Transplant Association – European Renal Association, 26(11), 3805–3810.