Walk into any supplement store and you’ll see the shelves adorned with what seems like an endless number of products making too-good-to-be-true claims: Lose weight in 24 hours! Lose two inches in two weeks! Between excessive praise and pushy salespeople, it can be difficult to know which supplements are reasonably worth trying—and why.
So, when exogenous ketone supplements started showing up on the market, we were honestly a bit skeptical: Are these new supplements worth incorporating into our regimens, and are their apparent benefits backed up by actual scientific research? Today’s post is dedicated to explaining how we came to conclude that yes, exogenous supplements are worth including into your daily routine, and we’re about to tell you why.
What are Exogenous Ketones?
Simply put, the term “exogenous” refers to things that come from outside the body. Supplements are therefore considered exogenous because you ingest them rather than producing the contents of that supplement inside the body. The opposite of exogenous is “endogenous,” which refers to things that you do produce within your body.
To define what “ketones” are, we need to briefly talk about how our metabolism works. Whenever you eat carbohydrates, they’re broken down into glucose (or sugar), which provides your body with the energy it needs to function; however, when you utilize a low-carb diet and don’t have enough glucose, your body adapts by looking for other sources of energy in the body. Eventually, it will turn to your fat cells. Whenever fats are broken down for energy, ketone bodies are produced as a result. Glucose is no longer your body’s primary fuel source, ketones are. (It’s important to note that ketones are always present in the blood, but their levels increase during periods of fasting, low-carbohydrate intake, and prolonged exercise.)
So, exogenous ketones are ketones that you ingest in supplement form. As it turns out, there are a plethora of benefits associated with taking exogenous ketones, which will be discussed later.
Some Background on Ketosis
“Ketones” are commonly associated with “ketosis,” a process that demands discussion here for a richer understanding of how these supplements work.
Ketosis occurs when your body stops using glucose as fuel and instead begins relying on ketones. The ketogenic diet revolves around this very concept and consists of eating a much higher ratio of fat in comparison to proteins and carbs (with these ratios varying depending on the specific type of ketogenic diet). The logic of eating this way is that it forces your body to stop burning glucose for fuel and instead break down fat into fatty acids, which corresponds with an increase in ketone bodies in your system as well.
The main ketone bodies that
are produced are acetone, acetoacetate, and beta-hydroxybutyrate (BHB), which are made in the liver when our body realizes we’re either restricting our carb intake, starving, or fasting. What makes ketones unique are their ability to move freely across the cell membrane and serve as an energy source for the brain, which fatty acids cannot do. The result: our bodies no longer rely on glucose for energy and less muscle is degraded as your body adjusts. In other words, ketone bodies offer a protective function in the sense that they stop your body from breaking down muscle for energy and provide energy themselves.
The Benefits of Exogenous Ketone Supplementation
Numerous studies have discussed the benefits of the ketogenic diet, which include: weight loss, blood glucose reduction, and an improvement of lipid markers. Recent studies have also looked into the benefits of the ketogenic diet and have shown promising results thus far in regards to conditions such as acne, cancer, traumatic brain injury, Alzheimer’s disease, and polycystic ovarian syndrome. Finally, research has also highlighted how the ketogenic diet can help prevent seizures and other symptoms of epilepsy.
In addition to the studies performed strictly regarding the effect of a ketogenic diet, there are also many current studies which highlight the benefits of the ketone bodies themselves:
1. Ketone bodies make your metabolism more efficient.
The result: the production of superoxide and glutathione increases, two antioxidants that protect our cells from oxidation.
2. Ketones can effectively fuel your muscles during workouts.
Your skeletal muscle has the ability to re-synthesize ATP (energy) from other substrates, including ketones. In fact, five times the normal amount of ketone bodies are “dumped” into your muscles during exercise, highlighting that ketone bodies are an effective energy source for working muscles.
Exogenous ketone supplements specifically can provide an advantage since they provide free energy, so to speak. Said differently, exogenous ketones require less oxygen per mole of carbon to oxidize. Translation: you get more bang for your buck when it comes to your energy needs.
3. They help your muscles after a workout too.
Research shows that nutritional ketosis can optimize protein synthesis after a workout, helping with recovery and also encouraging more fat oxidation in comparison to carbohydrate metabolism.
4. Ketone bodies can provide neurological enhancement.
Exogenous ketones can reduce neuronal loss and even improve neuronal functioning. Further, they can prevent damage from oxidation in an area of our brain called the hippocampus—the part of our brain in charge of memory, emotion, and the autonomic nervous system. Beyond that, ketones can provide a protective function against neurodegenerative diseases and illnesses.
In one small study, 20 subjects with Alzheimer’s disease or mild cognitive impairments were asked to consume a drink that helped elevate ketone levels in their body. They found that those with higher ketone levels experienced greater improvements in paragraph recall versus those with lower ketone levels.
5. Ketones show potential in the fight against cancer.
Due to the glucose reliant properties of proliferating cancer cells, ketogenic diets have demonstrated powerful tumor suppressing properties in a multitude of animal and human studies. The role that increased blood ketone levels played in this equation was once a mystery; however, a recent study published in the International Journal of Cancer highlights the promising potential of exogenous ketone use to suppress metastatic tumor growth. According to Poff et al. (2014), “Ketone administration elicited anticancer effects in vitro and in vivo independent of glucose levels or calorie restriction.” This study demonstrates that the lowered blood glucose commonly associated with a ketogenic diet is not the sole mechanism by which therapeutic benefits are achieved; it appears that ketones themselves may innately possess anticancer/cancer-modulating properties.
6. They give your mitochondria a helping hand.
As you might recall from your high school biology course, the mitochondria is the powerhouse of the cell, and it’s the main target of ketone bodies! Improving mitochondrial function provides advantages such as: increasing ATP (energy) synthesis, reducing oxidative stress, and reducing inflammation. Keep in mind: high levels of inflammation are predictors of a number of different diseases, so reducing inflammation does your body a huge favor!
7. Little to no side effects.
In a study of exogenous ketone supplementation, subjects had higher levels of ketone bodies with little to no side effects. This is especially good news given that a common complaint of MCT oil (medium-chain triglycerides) is that it can be hard on one’s gastrointestinal tract.
8. Ketones help with blood sugar regulation.
Studies of type 2 diabetes patients have pointed to the ways in which ketone bodies themselves can improve glycemic control and improve lipid markers, so much so that participants were able to stop using medications—even before they experienced weight loss.
Another study that measured blood glucose and cholesterol levels during a 38-day period of giving exogenous ketone supplements to rats found that supplementation significantly reduced blood glucose and inhibited weight gain as well.
Who Can Benefit from Exogenous Ketone Supplementation?
Let’s be real, the ketogenic diet isn’t easy. Many people state that it’s difficult to stick to, unpalatable, or hard on their bodies if they have trouble digesting fats. Furthermore, ketosis can be unsustainable in the long-term considering that just a small amount of carbohydrates or excess protein can kick you out of ketosis.
And what if you’re an elite athlete who is forced to restrict his/her calories and carbohydrate intake in order to make weight? Lord knows you need all the energy you can get to power through your training! That’s precisely where exogenous ketones come in; they allow you to reap the benefits of a low-calorie/low-carb state while still being able to refuel. Many anecdotal reports and testimonials of exogenous ketones note the amazing increase in energy levels they have experienced.
Endurance athletes can also benefit greatly from such supplementation because ketones provide more “fuel in the tank” for them to rely on during
competition (glycogen stores can only take you so far). And if you’re an on-the-go business executive or entrepreneur who generally enjoys the ketogenic diet, we all know endurance is just as important to you as it is for the athlete. Exogenous ketones help “kick you back into ketosis” at a much faster rate than waiting for the process to occur naturally. What does this mean? With ketone supplementation, you will experience increased energy and focus even during the beginning stages of your ketogenic journey—with none of the jitters or crash associated with caffeinated beverages.
Bottom line: Exogenous ketones provide the amazing benefits associated with a ketogenic state and ketone bodies without the hassle of drastically restricting carbs. A 2017 study in Nutrition & Metabolism puts it best: “We propose that exogenous ketone supplementation could provide an alternative method of attaining the therapeutic benefits of nutritional ketosis and further augment the therapeutic potential of the ketogenic diet.” And if you happen to be one of those low-carb nuts that prefers to steer clear of brown rice and sweet potatoes at all costs, you can say goodbye to the Low-Carb Flu and extreme fatigue—exogenous ketones are the supplement you have been waiting for to kick you into gear.
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