Most supplements rely on BHB as the source of their exogenous ketone bodies. BHB is converted to acetoacetic acid with a small quantity converted to acetone through a acetoacetate decarboxylase waste pathway. Some of the acetoacetic acid will enter the energy pathway using beta-ketothialase, which converts acetoacetic acid to two Acetyl-CoA molecules (see diagram below2).
Increased calcium levels in the bloodstream may contribute to the hardening of arteries (atherosclerosis), which in turn can lead to a heart attack.  Calcium from supplements enters the bloodstream in one bolus, whereas we usually tend to get calcium from foods in small doses from the breakdown process. This might explain why calcium from food doesn’t create the same risk that is introduced by calcium supplements. At first glance, it seems to be the case that high calcium intake –at least from supplements–may not be ideal.
That’s not to say that the supplements don’t work. They very well might. But they could also be useless—or even dangerous, says Christine Palumbo, RDN, Nominating Committee member for the Academy of Nutrition and Dietetics. As of right now, there’s no way to know. “Currently, there’s just not enough evidence from research studies to answer those questions,” Barnes adds.
Some general side effects of your body producing beta hydroxybutyrate is essentially the lull in time it takes to switch from carbohydrate metabolism to fat metabolism, which can take 3-4 days. This can lead to mood swings, fatigue, and general low energy. If you want to skip that step, we recommend taking exogenous BHBs to switch your body over effortlessly.

For the ketone esters, on the other hand, repeated doses of 20-30 grams in any one day may be possible. Thus these products may be able to maintain a modest level of ketonemia without dietary carbohydrate restriction. Thus some of the cardiac and brain fueling benefits may follow, not to mention the epigenetic effects limiting oxidative stress and inflammation. But given the recent observation that administered ketone esters markedly reduce circulating free fatty acids (Myette-Cote 2018) — possibly due to an insulin-tropic effect or direct suppression of lipolysis (Taggart 2005) — their sustained use in people with underlying insulin resistance may compromise their long-term benefits by promoting weight gain unless combined with carbohydrate restriction.

A growing number of people are giving it a try, thanks to exogenous ketone supplements that claim to launch your body into a state of ketosis within two and a half days—even if you’ve been living on pasta and cookies instead of following a low-carb diet. How can that be, though? And can that kind of rapid transformation actually be safe? Here’s what you should know.
The salts typically utilize sodium, potassium, calcium, or magnesium as the cation. Because these cations vary in molecular weight and valence (1+ or 2+), the amount of mineral delivered per gram of BOHB varies from 10% for the magnesium salt to 27% for potassium. Given that recommended daily intakes of these various minerals range from a few hundred milligrams up to 5 grams, whereas the daily ketone intake goal to mimic nutritional ketosis blood levels would need to be on the order of 50 grams, achieving this goal with ketone salts would severely challenge human dietary mineral tolerance.
Ketosis is a unique metabolic state where your body burns fat instead of glucose for fuel. Glucose is a simple sugar molecule derived from carbohydrates. Your body prefers using glucose to using fat and protein to make energy. This is because glucose it is easy to burn as it doesn't require much energy. On the other hand, your body uses fat and protein to build and repair tissue and make hormones.
Blood d-βHB, pH, bicarbonate (HCO3-) and electrolytes measured in arterialized blood samples from resting subjects (n = 7) following a ketone ester or salt drink containing 3.2−1 of βHB. Shaded areas represent the normal range. Values are means ± SEM. (A) Venous blood d-βHB. (B) Arterialized blood pH. (C) Blood bicarbonate. (D) Blood potassium. (E) Blood sodium. (F) Blood chloride. †p < 0.05 difference between KE and KS, *p < 0.05 difference from baseline value.
Again, there are very interesting animal studies plus some single case reports and small uncontrolled trials of humans with neurodegenerative disease and cancer given ketogenic diets and/or exogenous ketones (Murray 2016, Poff 2015, Roberts 2017, Newport 2015, Cunnane 2016). In some cases where the patient does not have the cognitive resources to comply with a well-formulated ketogenic diet, or where target blood levels of BOHB that work in animals are hard to achieve in humans by diet alone, supplemental ketones may have an important role to play in the prevention, management, or reversal of these disease categories.
Blood d-βHB concentrations rapidly increased to a maximum of 2.8 ± 0.2 mM following the KE drink and to 1.0 ± 0.1 mM following the KS drink (Figure ​(Figure1A).1A). After the peak was reached, blood d-βHB disappearance was non-linear, and followed first order elimination kinetics as reported previously (Clarke et al., 2012b; Shivva et al., 2016). d-βHB Tmax was ~2-fold longer following KS drinks vs. KE drinks (p < 0.01, Figure ​Figure1B),1B), and KS d-βHB AUC was ~30–60% lower than the KE drink (p < 0.01, Figure ​Figure1C1C).
If you've tried this type of diet before, or if you've done some research about it beforehand, then you should know that these ten tricks are necessary to get into a ketogenic state quickly, but you will be surprised at the number of people who actually jump on the ketogenic bandwagon without knowing any of the basics first. Remember: A good working knowledge coupled with an effective meal plan can go a long way.
When you restrict carbs, the kidneys excrete a lot of sodium. Not replacing this sodium can leave you feeling light headed. I recommend having a big glass of spring water with ½ teaspoon of Celtic sea salt twice a day (first thing in the morning and midafternoon are two times that work well). A long with this, make sure you use a lot of salt on your meals.
The product does not work. I have taken one scoop daily and for last two days two scoops (once in the morning and once in the night). I also do intermittent fast i.e. no food from 8 pm - next day 2 pm other than this powder in the morning. My food is 1500 calories with 60% fat, 30% protein and 5% carbs. I used to achieve ketosis naturally prior to using the powder. But now, there is no ketosis. This product does not work. I am wondering how on earth did they pick up so many reviews, unless it is faked marketing.
Until there is more definitive information on the necessary blood levels and the differing proportions of BOHB an AcAc to optimize cellular and organ functions, it will be difficult to specify the dosing and duration of supplemental ketones. However for fuel use, and very likely for exercise performance as well, sustained blood levels of BOHB in the range of 0.5 mM to 1.0 mM are likely to be required. This is achieved physiologically by an estimated ketone production of 50-100 grams per day in a keto-adapted human.
North Americans typically live pro-inflammatory, pro-disease lives (think about your everyday: likely sitting in a flexed position for hours on end, not enough natural sunlight, not enough movement, artificial food stuffs, artificial colouring, going to bed late, blue light exposure, less in-person contact with our loved ones, late night snacks, the list goes on and on).
Even though endurance athletes can train in a carb depleted state, they will generally consume carbohydrates in the lead up to a race (the athlete is seeking to increase the ability to run off fats by training in a carb depleted state, then benefiting from both fats AND carbs come race day). Likewise, with the brain, even though the brain can function off ketones, does it mean it’s the best state for brain function?
Divided attention involves processing multiple streams of information. The game involves observing a pond full of koi fish swimming around, and tapping each fish only once to feed it a pellet without feeding any fish previously fed. Each level adds more fish with increasing speed and redirection. It’s similar to pretending to be an air-traffic controller who must keep track of every plane on their radar.
This may have been mentioned, I haven’t checked all comments, but glutamine causes gluconeogenesis so that may explain why it affects Ketosis. Whenever I took a glutamine powder supplement for gut healing, I noticed I would “feel” less Ketogenic and I knew it was affecting me adversely. Glycine (which is also in bone broth) also has this effect I believe. Apparently some amino acids are just more easily converted to glucose.
Hey Staci, great to hear you’re getting back into it! To answer your question, it really depends on the individual but there are definitely things you can do to get back into ketosis faster – working out to deplete your glycogen stores or implementing intermittent fasting into your regimen – these are 2 common ways that should kick start you back in the right direction!
Caveat emptor: the following post doesn’t come close to answering most of these questions. I only document my experience with BHB salts (and a non-commercial version at that), but say little to nothing about my experience with BHB esters or AcAc esters. But it will provide you will some context and understanding about what exogenous ketones are, and what they might do for athletic performance. We’ll likely podcast about the questions and topics above and cover other aspects of exogenous ketones in more detail.

Affiliate Disclosure: There are links on this site that can be defined as affiliate links. This means that I may receive a small commission (at no cost to you) if you purchase something when clicking on the links that take you through to a different website. By clicking on the links, you are in no way obligated to buy.

Medical Disclaimer: The material on this site is provided for informational purposes only and is not medical advice. Always consult your physician before beginning any diet or exercise program.

Copyright ©