One promising solution for individuals looking to lose weight and supplement their ketogenic diet is exogenous ketone supplements. These supplements provide an exogenous/external source of the same ketones (generally just beta-hydroxybutyrate) that your body makes naturally/endogenously.
Exogenous Ketones for Getting into Ketosis
Exogenous ketone supplements greatly expedite the process of getting into and maintaining a state of ketosis, making them a great addition to a keto diet. BHB supplements can help by improving things like cognitive function, energy levels, appetite control, and even longevity.
In this article, we’ll take a closer look at exogenous ketone supplements, how they work, and the best ones available.
What is BHB?
If you’re exploring the keto diet and which supplements to take, you’ve probably stumbled upon something called BHB.
BHB is an acronym for beta-hydroxybutyrate, which is generally the only ketone found in exogenous ketone supplements. So when products market themselves as a BHB supplement, this is just another term for exogenous ketone supplement.
In the absence of carbs, our bodies instead produce BHB and acetoacetic acid from fat, which leads to energy production. You’ll always want to be sure that any exogenous ketone supplements you purchase contain BHB as they are the most efficient and beneficial ketone body.
Any supplement worth its salt should meet three basic criteria: it contains BHB salts, it’s made with only natural flavors, and contains no carbs! Basically, you want to ensure the product doesn’t contain any poor ingredients that do not directly improve your health.
Ketone Salts & Ketone Esters
As mentioned in the previous section, exogenous ketones typically come in the form of BHB, with the three types being ketone oils, ketone salts, and ketone esters.
Ketone Oils: One method used for boosting ketone levels, albeit indirectly, is medium chain triglycerides (MCTs). Our body’s cells metabolize MCTs rapidly and can use them as a substrate to produce ketones. While this is a very valid option to supplement the keto diet, MCTs offer an indirect (and slower) way for your body to produce more ketones on its own.
Ketone Salts: Ketone salts are naturally-derived compounds that mix sodium, calcium, or potassium to help improve absorption. All commercial supplements you find on the market currently are made up of BHB ketone salts, which are also commonly labeled “BHB Mineral Salts” and “Ketone Mineral Salts”. BHB is the preferred ketone in exogenous ketone supplements because it’s more potent than acetone and acetoacetic acid, it’s more palatable, and it appears to have distinct signaling properties that govern the many benefits of ketosis.
Ketone Esters: Unlike ketone salts, ketone esters are synthetically-made compounds that link a ketone body to alcohol which is then metabolized in the liver to a ketone. At the moment, ketone esters are mostly only used in research for testing in raising ketone blood levels. (They are also unpalatable, making them less desirable to consume than ketone salts.)
While ketone esters are not currently available in products on the market today, research shows from a four-week study on rats that ketone esters were more effective than ketone salts at reducing weight gain.  However, by week four, BHB salts paired with MCT oil had matched the body weight results of the ketone esters.
It’s also important to note here that raspberry ketone is not related to exogenous ketone supplements and BHB, as its name suggests. While a popular diet supplement in and of itself, raspberry ketone is a distinct plant-based ketone that has no impact on ketosis and the evidence that it promotes fat loss is lacking.
So Which Ketone Supplement Works Best?
While they have can have a few side effects, such as upset stomach, ketone salts are by far the best and most popular exogenous ketone supplements. BHB supplements are becoming quite popular and more readily available, generally coming in the form of flavored powder – like Keto BHB.
While esters may appear to be a great choice in quickly boosting the body’s ketone levels, these supplements come with some unpleasant side effects such as a foul taste, gas, severe diarrhea, and bloating.
Keto MCT powder is another great choice but is typically paired with exogenous ketone salts for added synergy.
The Benefits of Exogenous Ketone Supplements
During a keto diet, your body will naturally produce three ketones as part of fat metabolism: BHB, acetoacetate, and acetone. Your body benefits from the extra ketones found in exogenous supplements by promoting deeper ketosis (or helping you get into ketosis fast).
Realistically, there will be times when you’re unable to maintain a steady state of ketosis. One of the biggest advantages of ketone supplements is that they help get you back into ketosis quickly instead of having to wait. You can take them before a workout for extra energy, while you’re fasting, or in between meals for a clean mental boost and fewer food cravings.
To recap, exogenous ketone supplements can help improve overall health and longevity through a multitude of ways, including:
- Quicker weight loss
- Reducing hunger
- Regulating blood glucose
- Reducing the risk of certain diseases
- Boosting mental focus
- Decreasing inflammation
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