The reality that rings true for the fitness and supplement industry is that there will always be a trend. Whether it be the diet that promises to be the end-all for fitness goals or the supplement that promises to redefine a category, we are always searching for the latest and greatest. The most recent emergence as you are probably aware of by now is the ketogenic diet and actually combines both a diet trend and a whole category of supplements geared toward helping you live the ‘keto’ lifestyle.
For those that weren’t already aware, the ketogenic diet really isn’t new at all. It was originally devised when endocrinologist Rollin Woodyatt observed that three ketone bodies were produced by the liver as a result of starvation or a high fat/low carb diet. The observation then made it’s way into dietary practice and was introduced in the 1920’s as an alternative to non-mainstream fasting and therapy for epilepsy. It saw noteable success, howoever it started to be abandoned with the introduction of anticonvulsant therapies (1). It saw a minor resurgence in 1994 for the same type of treatment, but it wasn’t until the emergence of low carb dieting around 2007 that we saw the ketogenic diet and variations make a large comeback along with the widespread ‘carbophobia’ trend before once again, seeming to receed a bit. Now, that brings us to present day and the ketogenic diet is once again in the spotlight with many touting to live the ‘keto lifestyle’ and the supplements to go along with it.
Traditionally, MCT oil was used after research in the 1970’s demonstrated that there were more ketones produced by MCT per unit of energy due to them being transported quickly to the liver via the hepatic portal vein, as opposed to the lymphatic system (2). These additional ketone bodies allow slightly more protein and carbohydrates to be included as MCTs are metabolized into ketones even in the presence of dietary carbohydrates.
These days, much like the MCT oil, BHB (β-hydroxybutyrate) salts have emerged onto the scene to play a part in the keto movement. These BHB salts are simply compounds consisting of sodium (Na+), potassium (K+), and the ketone body β-hydroxybutyrate. In products containing such BHB salts, the individual components are being held together by ionic bonds and when ingested, they are absorbed into the blood where it dissociates into free Na+, K+, and BHB, thus directly and immediately putting ketones into your blood.
What is the State of True Ketosis?
Now, with these things in mind, one misconception and marketing ploy is that those unfamiliar with the ketogenic diet may be lead to think that simply ingesting ketogenic products like BHB salts will put them in a ketogenic state, however that isn’t the case. True ketosis is a metabolic state in which dietary carbohydrates are in such low amounts that there is a reliance on almost exclusively ketone and fatty acid metabolism.
While it may sound relatively simple, a little background will help you understand the physiology behind it a little more. For brain function, it requires around 400 calories per day, running almost exclusively on glucose, meaning you need a minimum of 100g of glucose (carbohydrates) per day just to fuel it. The human body is an amazing machine that constantly adapts to the stresses placed up on it and carb restricted diets, which cut off the glucose supply to the brain, are one such stress. To counteract, the body combats by borrowing and/or converting sugars from other areas or sources within the body. As a safeguard in this event, it is supplied by the liver which stores glucose and can pump it into the blood to fuel the brain.
The liver can store around 100 grams of glucose, allowing you to run for about a day before the stores are depleted. If you run it this low, the next logical place you would think glucose could come from would of course be our skeletal muscle that can store 400-500 grams of glycogen. This is great in numbers, but it’s the equivalent of standing outside of a bank vault because there is the lack of the enzyme that can break down the glycogen and make it readily available to your brain.
Rest assured, your body has a solution for everything and in the absence of any more available glucose from carbohydrates, it once again relies on the liver to deliver. In this situation, the liver begins to produce the aforementioned ketone bodies to be released into the blood for use by your brain and other tissues for energy.
If you are unaware, this is critical because when one is ‘burning fat’, whether it is in the form of a calorie deficit or ketogenic state, what is really happening is a fatty acid molecule is undergoing a chemical change. Essentially, when you “burn fat,” you’re really taking a fatty acid molecule and converting it to something called acetyl CoA.
In the ketogenic state, the amount of fat that your liver is using for energy is so high, there is an excessive amount of this acetyl CoA that it starts converting it into the ketone bodies. As a result and due to the need for a new energy source, the body happily begins dumping these ketone bodies into the blood stream for energy. Once this process is underway, and the body is doing this continually, the body has officially reached a state of true ketosis.
No Magic Switch…
Now that you know what ketosis is, here is a little insight for the process. It takes some time (up to 2 weeks for some) for the body to transition into a ketogenic state so you won’t even come close to achieving a true state of ketosis by cutting out carbs for a day or two. Anyone that has done a true keto diet understandably will get annoyed when someone says they are going to ‘try keto’ for a week as by they will most likely barely be getting into true ketosis by the time they end the experiment.
The same can be said for the supplements on the market such as the BHB salts or even MCT oil that has come back in to prominence. There’s no supplement that can make you go into a state of ketosis as this must be done through dietary manipulation, however it is easy for it to get misconstrued when people hear of products that discuss ketones and the like. Further supporting this misconception is that a common way of testing for the state of ketosis is the use of urine testing strips. While these strips do serve a helpful purpose, it must be remembered that simply having ketones present in urine doesn’t indicate the state of ketosis. By ingesting BHB salts or MCT oil, you are providing exogenous ketones that will of course show up in urine and cause a reading of false ketosis.
Furthermore, for those utilizing the ketogenic diet for fat burning, if you are ingesting exogenous ketones or using MCT oil, it can actually hinder your fat burning as your body can use these ketones or MCTs as a readily available fuel source rather than the ones being released from your body to burn.
So What Value Do Exogenous Ketones Have?
When it comes to MCT oil and BHB salts, they both do indeed serve a helpful purpose, but it must be kept in context. MCT oil is a great source of energy and as stated before, produces more ketone bodies compared to other long chain fatty acids. They are easily used for energy, very similar to carbohydrates (via the ketone pathway) and have secondary benefits on metabolism (3) and blood sugar regulation (4).
As for the new BHB salts, they have been emerging as both a standalone product as well as being featured in products such as pre-workouts. They provide an instant and immediate source of ketones in the blood stream, translating to providing energy via the form of ketones. They are most promising from a performance standpoint, offering the potential for stimulating the metabolic shift away from glucose (5) and improving mental cognition (6) all while providing an immediate fuel source from ketones.
For both the MCT oil and BHB salts, they can help reduce the impact of carbohydrate intake on ketosis to some degree, but to what degree is still being examined. Among other items that are still being researched is that there may be the potential for BHB salts to increase exercise capacity via reducing oxygen consumption, and that will be some potentially exciting research in itself.
1. The ketogenic diet: one decade later. Freeman, JM and EH, Kossof. 3, March 2007, Pediatrics, Vol. 119, pp. 535-543.
2. Medium-chain triglycerides as a therapy for intractable childhood epilepsy. Huttenlocher, PR and Wilbourn, AJ. 11, November 1971, Neurology, Vol. 21, pp. 1097-1103.
3. Postprandial thermogenesis in lean and obese subjects after meals supplemented with medium-chain and long-chain triglycerides. Scalfi, L and Coltori, A. 5, May 1991, Vol. 53, pp. 1130-1133.
4. Medium Chain Triglyceride Oil Consumption as Part of a Weight Loss Diet Does Not Lead to an Adverse Metabolic Profile When Compared to Olive Oil. St-Onge, Marie-Pierre and Bosarge, Aubrey. 5, October 2008, J Am Coll Nutr, Vol. 27, pp. 547-552.
5. Ketones Suppress Brain Glucose Consumption. LaManna, Joseph and Salem, Nicolas. 2009, Adv Exp Med Biol, pp. 301-306. 645.
6. Effects of beta-hydroxybutyrate on cognition in memory-impaired adults. Reger, MA. 3, March 2004, Neurobiol Aging, Vol. 25, pp. 311-314.