My two cents: I wouldn’t take ketone supps if not on some sort of low(ish) carb diet because the idea of high levels of BOTH fuels (ie, ketones AND glucose) doesn’t seem physiologically appropriate… more like a recipe for disaster, and by “disaster,” I mean “out-of-control production of Reactive Oxygen Species” — this might not matter if you’re an athlete looking for a quick performance boost, because the fuels are going to be cleared rather quickly… not so much if you’re a desk jockey.
Ketostix are very unreliable. There are many factors which can alter results such as hydration level, if you’ve worked out recently and the amount of unused ketones in your body to name just a few. Never rely of Ketostix to determine whether you are in ketosis or not. The Precision Xtra blood ketone monitor is the gold standard for testing for ketones in your body. After following a ketogenic diet for a while, you should be able to tell if you are in ketosis or not by the way you feel.

Although decreases in FFA, TG and glucose occurred, there were no significant differences between the KE and KS drinks or with intake amount. Ingestion of ketone drinks significantly decreased overall mean plasma FFA from 0.7 to 0.4 mM, TG from 1.1 to 0.9 mM and glucose from 5.7 to 4.8 mM after 1 h (all p < 0.05). Concentrations were the same as at baseline by 4 h, with FFA at 0.6 mM, TG at 0.9 mM and glucose 5.1 mM (Figures 2A–C). There was a rise in insulin concentrations 30 min following all drinks, probably due to the small amount of carbohydrate in the sweetener (Figure ​(Figure2D2D).

Do I still follow a ketogenic diet? Not anymore. I was strict keto for 12 weeks – enough time to experiment and learn about it. I did enjoy parts (lots of fat!) but I don’t see it as a sustainable way of eating, nor did I benefit from it health or sports performance wise (more on this in an upcoming article). But, I was following a strict keto diet – sans carbs. I think if I were to follow a ketogenic diet AND incorporate a regular carb refeed then the results may be different.
I just read your comment and was wondering the same thing. I can see how exogenous ketones can be a great energy boost to people on the ketogenic diet, but I don’t see how they can speed fat loss. Keto OS claims you can eat higher carbs and still see the benefits of ketosis. I don’t see how that is possible. the whole point of weight loss through ketosis is the breaking down of your own fat to create energy. I don’t see how exogenous energy will increase natural fat breakdown. I wish I could get a straight answer to this from somebody.
All of the data I’ll present below were from an experiment I did with the help of Dominic D’Agostino and Pat Jak (who did the indirect calorimetry) in the summer of 2013. (I wrote this up immediately, but I’ve only got around to blogging about it now.) Dom is, far and away, the most knowledgeable person on the topic of exogenous ketones. Others have been at it longer, but none have the vast experiences with all possible modalities (i.e., esters versus salts, BHB versus AcAc) and the concurrent understanding of how nutritional ketosis works. If people call me keto-man (some do, as silly as it sounds), they should call Dom keto-king.

Beta-hydroxybutyrate (BHB) is a ketone body produced in the liver naturally under conditions when glucose isn’t very available. Other types of ketones produced via the restriction of dietary carbohydrates are acetoacetate and acetone. A VLCHF or ketogenic diet provides the optimal conditions for this process. Fasting, exercise and/or basic caloric restriction are all also methods for promoting ketogenesis (literally, the making of ketones).

Beta-Hydroxybutyrate (BHB) is naturally ketone body that is produced when free fatty acids are broken down in the liver. The other two types of Ketone bodies are acetoacetate (AcAc) and acetone. Ketones provide pure energy to fuel the human brain and other tissues. The elevation in ketones in your blood have been a rapidly emerging area of research and studies are continuing to show improvements in performance, brown adipose tissue, and several other possible applications.
It’s sometimes the case that a person has been attempting to transition to a state of ketosis, but in spite of their best efforts, they seem stuck in a kind of limbo where they’re eating hardly any carbs, but they don’t seem to be losing weight or experiencing the other benefits of the keto diet. But the science is the science, which means if you’re doing everything right you should be in ketosis. If you’re not, or you seem to be drifting in and out of a keto state, it’s not your body’s fault, it’s your diet.
This was a big surprise. We were at the very least expecting that drinking a ketone supplement would cause blood ketones to rise, but an average increase of 0.33 mmol/L is very small. The supplement associated with the highest average increase in blood ketones was Prüvit’s Keto-OS Max, but it was only an increase of 0.6 mmol/L. Brianna Stubbs, the ketone researcher I consulted with, agrees that an increase of below 2.0-3.0 mmol/L is unlikely to be of much use.
Keep these studies in mind as your body tries to play tricks on you during your first day of fasting.  Even after three days of fasting, health complications are highly unlikely. However, it is important to know about the possible issues that can be caused by fasting. If you choose to incorporate fasting into your daily diet, you typically want to eat every day as well. Occasionally going on a longer period of fasting.
 Effects of beta-hydroxybutyrate on cognition in memory-impaired adults. – Glucose is the brain’s principal energy substrate. In Alzheimer’s disease (AD), there appears to be a pathological decrease in the brain’s ability to use glucose. Neurobiological evidence suggests that ketone bodies are an effective alternative energy substrate for the brain. Elevation of plasma ketone body levels through an oral dose of medium chain triglycerides (MCTs) may improve cognitive functioning in older adults with memory disorders. On separate days, 20 subjects with AD or mild cognitive impairment consumed a drink containing emulsified MCTs or placebo. Significant increases in levels of the ketone body beta-hydroxybutyrate (beta-OHB) were observed 90 min after treatment (P=0.007) when cognitive tests were administered. beta-OHB elevations were moderated by apolipoprotein E (APOE) genotype (P=0.036). For 4+ subjects, beta-OHB levels continued to rise between the 90 and 120 min blood draws in the treatment condition, while the beta-OHB levels of 4- subjects held constant (P<0.009). On cognitive testing, MCT treatment facilitated performance on the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-cog) for 4- subjects, but not for 4+ subjects (P=0.04). Higher ketone values were associated with greater improvement in paragraph recall with MCT treatment relative to placebo across all subjects (P=0.02). Additional research is warranted to determine the therapeutic benefits of MCTs for patients with AD and how APOE-4 status may mediate beta-OHB efficacy.

Elliot received his BS in Biochemistry from the University of Minnesota and has been a freelance writer specializing in nutritional and health sciences for the past 5 years. He is thoroughly passionate about exercise, nutrition, and dietary supplementation, especially how they play a role in human health, longevity, and performance. In his free time you can most likely find him lifting weights at the gym or out hiking through the mountains of Colorado. He will also host the upcoming BioKeto podcast. You can connect with him on Facebook ( and Instagram (@eazy_ell)
The ketone esters are, hands-down, the worst tasting compounds I have ever put in my body. The world’s worst scotch tastes like spring water compared to these things. The first time I tried 50 mL of BHB monoester, I failed to mix it with anything (Dom warned me, but I was too eager to try them to actually read his instructions). Strategic error. It tasted as I imagine jet fuel would taste. I thought I was going to go blind. I didn’t stop gagging for 10 minutes. (I did this before an early morning bike ride, and I was gagging so loudly in the kitchen that I woke up my wife, who was still sleeping in our bedroom.) The taste of the AcAc di-ester is at least masked by the fact that Dom was able to put it into capsules. But they are still categorically horrible. The salts are definitely better, but despite experimenting with them for months, I was unable to consistently ingest them without experiencing GI side-effects; often I was fine, but enough times I was not, which left me concluding that I still needed to work out the kinks. From my discussions with others using the BHB salts, it seems I have a particularly sensitive GI system.

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