At day 29 of the study, animals were euthanized and brain, lungs, liver, kidneys, spleen and heart were harvested and weighed. Organ weights were normalized to body weight. Ketone supplementation did not significantly change brain, lung, kidney, or heart weights compared to controls (Fig. 5a, b, d, f). MCT supplemented animals had significantly larger livers compared to their body weight (p < 0.05) (Fig. 5c). Ketone supplements BMS + MCT, MCT and BD caused a significant reduction in spleen size (BMS + MCT p < 0.05, MCT p < 0.001, BD p < 0.05) (Fig. 5e). Rats administered KE gained significantly less weight over the entire study compared to controls. BMS + MCT, BMS, and BD supplemented rats gained significantly less weight than controls during weeks 2 – 4, and MCT animals gained less weight than controls at weeks 3 – 4 (Fig. 6). Increased gastric motility (increased bowel evacuation and changes to fecal consistency) was visually observed in rats supplemented with 10 g/kg MCT, most notably at the 8 and 12-h time points. All animals remained in healthy weight range for their age even though the rate of weight gain changed with ketone supplementation [53–54]. Food intake was not measured in this study. However, there was not a significant change in basal blood glucose or basal blood ketone levels over the 4 week study in any of the rats supplemented with ketones (Fig. 7).
While the KetoneAid folks have been seeing tremendous success working with elite athletes to improve athletic performance, I thought it would be interesting to quantify the effects of ketone esters on cognitive performance. For the week prior to taking the ketones, I re-established baseline scores in a number of cognitive testing areas using Lumosity*:
Hypoglycemia: why not to be concerned – Taking exogenous ketones can drive blood glucose levels quite low, but you are not likely to feel the typical symptoms of hypoglycemia. This is because when ketone levels are high enough, they dominate as fuel in the brain; hence, you will feel just fine despite having low blood glucose. A highly-cited study by George Cahill, found elevated ketone levels could protect fasted participants when they were administered insulin to induce hypoglycemia.
Your body uses the energy source that is the easiest to use, in our case this is glucose. Glucose is just a type of sugar. As our body cannot store glucose as such it stores the extra glucose in form of glycogen that is stored in our liver and muscles. To initiate production of ketones in your body as fast as possible you must deplete your body of glycogen reserves. The best way to do this is a simple 24 hours fast. This will deplete your glycogen stores as fast as possible. If you don’t over eat for dinner or you even skip it all together you will already wake up in state of mild ketosis the next morning due to the overnight fast. Here are also described some signs that you are in Ketosis already.

This is probably one of the most understood notions of a true ketogenic diet (and the difference between a keto diet and a low carb diet). An optimal ketogenic diet will be low in carbohydrates AND protein. Many people who have experimented with low carb dieting simple reduce carbs and increase protein. A big reason behind this is due to the misconception that ‘’excess fat is bad – which is untrue, more on this HERE). However, excess protein can be converted to glucose (blood sugar) through a process called gluconeogenesis.

Before that though, I do want to touch on MCT oil and it’s impact on ketone levels. MCT – or Medium Chain Triglyceride – are fatty acids that bypass the liver – and become quick energy for the brain and muscles. As they are a fat based energy source (and not a carbohydrate) they are quickly converted into ketones. This means MCT oil is a great way to boost ketone levels in the body.
So I’ve been primarily on a Keto diet for almost 6 months. During this time, I have fine tuned a lot to get my ketone levels up (Eating more fat and less protein). Most recently, I have used blood measurements for my ketone levels and I fluctuate between .6 and 2.6. The higher readings I get on the days I workout in the morning (about 5 hours before I draw blood and take a reading). I don’t have any problems sticking to the diet. It only seems to get easier. I’ve also incorporated 16 hour fasts which also are becoming easier over time. My priority and motivation for doing a keto diet is first and foremost weight loss. So far I have lost 40 pounds and I need to lose about 20 more. I do however want to improve my performance (running) and strength (I am doing the Stronglifts 5×5 program now).
Beta hydroxybutyrate floats around in your blood, and importantly, can cross different barriers to be able to be turned into energy at all times. One of the most important areas where this happens is in the brain. The blood-brain barrier (BBB) is usually a very tightly regulated interface that doesn’t allow the transfer of many molecules, but since BHB is such a rock star and so hydrophilic, your brain knows to let it in so it can bring energy to the party at any time. This is one of the main reasons why increased levels of ketosis lead to improved mental clarity, focus and reduction in neurodegenerative diseases.
Hi. Thanks for the informative article! I have fallen down the exogenous ketone rabbit hole for the last 2 days trying to figure everything out. I am currently on a nutritional ketonic diet but after 8 months, I am finding it difficult to stay on it 100%. I would like to remain on a low-carb diet, but also have a little more flexibility in my food choices. If you take the expense out of the equation, which product would you recommend for someone who wants to use ketosis as a method of weight loss? Thank you so much.
An effective ketosis program requires that you control your appetite. Caffeine has been proven to be an excellent appetite suppressant. It can curb your appetite and reduce your cravings for food. If you are finding it hard to implement intermittent fasting, try to introduce coffee into the equation. If you are not into coffee drinks, try to take tea or use caffeine pills. Both of them contain caffeine, which can help you to adjust smoothly into fasting.

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).
Will taking exogenous slow down my fat loss? Since now before digging into my body for energy/ketones, I will first use up the exogenous ketones I ingest. Also do exogenous ketones somehow help get even more keto adapted, keeping in mind I have been on a strict keto diet without a problem and don’t mind it at all. Outside of performance improvements, do you think exogenous ketones is for someone like me who is primarily looking for fat loss.

Taking exogenous ketones not only eliminates the need to follow a strict ketogenic diet to achieve ketosis (so you can have your high carb cake and eat it too), it can also help users get there faster. “They can expedite the process of getting into ketosis and becoming fat adapted,” Davis explains. “They can also help people push past the keto flu and potentially experience more mental energy and clarity than from diet alone.”
Recent studies suggest that many of the benefits of the KD are due to the effects of ketone body metabolism. Interestingly, in studies on T2D patients, improved glycemic control, improved lipid markers, and retraction of insulin and other medications occurred before weight loss became significant. Both βHB and AcAc have been shown to decrease mitochondrial reactive oxygen species (ROS) production [36–39]. Veech et al. have summarized the potential therapeutic uses for ketone bodies [28, 40]. They have demonstrated that exogenous ketones favorably alter mitochondrial bioenergetics to reduce the mitochondrial NAD couple, oxidize the co-enzyme Q, and increase the ΔG’ (free enthalpy) of ATP hydrolysis [41]. Ketone bodies have been shown to increase the hydraulic efficiency of the heart by 28 %, simultaneously decreasing oxygen consumption while increasing ATP production [42]. Thus, elevated ketone bodies increase metabolic efficiency and as a consequence, reduce superoxide production and increase reduced glutathione [28]. Sullivan et al. demonstrated that mice fed a KD for 10–12 days showed increased hippocampal uncoupling proteins, indicative of decreased mitochondrial-produced ROS [43]. Bough et al. showed an increase of mitochondrial biogenesis in rats maintained on a KD for 4–6 weeks [44, 45]. Recently, Shimazu et al. reported that βHB is an exogenous and specific inhibitor of class I histone deacetylases (HDACs), which confers protection against oxidative stress [38]. Ketone bodies have also been shown to suppress inflammation by decreasing the inflammatory markers TNF-a, IL-6, IL-8, MCP-1, E-selectin, I-CAM, and PAI-1 [8, 46, 47]. Therefore, it is thought that ketone bodies themselves confer many of the benefits associated with the KD.
The effects of ketone drinks on endogenous insulin secretion are unclear. Whilst the small increase in plasma insulin after KE and KS drinks may have been due to the small quantity of dextrose in the diluent, it has been proposed that ketones could potentiate or even stimulate insulin secretion. Isolated pancreatic islets secreted insulin when stimulated by ketones at glucose concentrations of >5 mM (Biden and Taylor, 1983), and small amounts of insulin are secreted in vivo following exposure to exogenous ketones in animals (Madison et al., 1964; Miles et al., 1981). In response to an intra-venous 10 mM glucose clamp, ketone ester drinks increased glucose uptake and plasma insulin (Holdsworth et al., 2017). The increases in insulin with ketone drinks taken whilst fasted were small compared to the increases seen when the ketone ester drink was consumed with a meal and with consumption of a dextrose drink. Furthermore, the lack of difference in peak plasma insulin between the two latter conditions indicates that nutritional ketosis did not inhibit or increase normal carbohydrate induced insulin production.
Every 7 days, animals were briefly fasted (4 h, water available) prior to intragastric gavage to standardize levels of blood metabolites prior to glucose and βHB measurements at baseline. Baseline (time 0) was immediately prior to gavage. Whole blood samples (10 μL) were taken from the saphenous vein for analysis of glucose and βHB levels with the commercially available glucose and ketone monitoring system Precision Xtra™ (Abbott Laboratories, Abbott Park, IL). Blood glucose and βHB were measured at 0, 0.5, 1, 4, 8, and 12 h after test substance administration, or until βHB returned to baseline levels. Food was returned to animals after blood analysis at time 0 and gavage. At baseline and week 4, whole blood samples (10 μL) were taken from the saphenous vein immediately prior to gavage (time 0) for analysis of total cholesterol, high-density lipoprotein (HDL), and triglycerides with the commercially available CardioChek™ blood lipid analyzer (Polymer Technology Systems, Inc., Indianapolis, IN). Low-density lipoprotein (LDL) cholesterol was calculated from the three measured lipid levels using the Friedewald equation: (LDL Cholesterol = Total Cholesterol - HDL - (Triglycerides/5)) [51, 52]. Animals were weighed once per week to track changes in body weight associated with hyperketonemia.

If you’re wondering how to get into ketosis in 24 hours, and whether it’s even possible with such a short turnaround time, then combining a keto diet with intermittent fasting is a must. I am a massive advocate of not only the ketogenic diet but also the practice of daily fasting – I swear by it! It’s not for everyone as it does require a lot of discipline to pull off. But if you can commit to it, the benefits in my opinion are well worth it. So you may be wondering what intermittent fasting is? Well, it’s the practice of performing a daily fast from food and (caloric) drinks for at least 16 hours of the day.
Ketone monoester and diester compounds may circumvent the problems associated with inorganic ion consumption in KS drinks. KE ingestion rapidly increased blood ketone concentrations to >5 mM in animals (Desrochers et al., 1995a,b; Clarke et al., 2012a) and the first oral, non-racemic KE for human consumption, (R)-3-hydroxybutyl (R)-3-hydroxybutyrate, raised blood βHB concentrations to 3–5 mM in healthy adults (Clarke et al., 2012b; Shivva et al., 2016) and athletes (Cox et al., 2016; Holdsworth et al., 2017; Vandoorne et al., 2017). However, the pharmacokinetics and pharmacodynamics of this KE with confounding factors, such as prandial state or multiple KE drinks, have not been characterized.
Ketone supplementation did not affect the size of the brain, lungs, kidneys or heart of rats. As previously mentioned, the rats were still growing during the experimental time frame; therefore, organ weights were normalized to body weight to determine if organ weight changed independently to growth. There could be several reasons why ketones influenced liver and spleen weight. The ratio of liver to body weight was significantly higher in the MCT supplemented animals (Fig. 5). MCTs are readily absorbed in the intestinal lumen and transported directly to the liver via hepatic portal circulation. When given a large bolus, such as in this study, the amount of MCTs in the liver will likely exceed the β-oxidation rate, causing the MCTs to be deposited in the liver as fat droplets [94]. The accumulated MCT droplets in the liver could explain the higher liver weight to body weight percentage observed with MCT supplemented rats. Future toxicology and histological studies will be needed to determine the cause of the observed hepatomegaly. It should be emphasized that the dose in this study is not optimized in humans. We speculate that an optimized human dose would be lower and may not cause hepatomegaly or potential fat accumulation. Nutritional ketosis achieved with the KD has been shown to decrease inflammatory markers such as TNF-α, IL-6, IL-8, MCP-1, E-selectin, I-CAM, and PAI-1 [8, 46], which may account for the observed decrease in spleen weight. As previously mentioned, Veech and colleagues demonstrated that exogenous supplementation of 5 mM βHB resulted in a 28 % increase in hydraulic work in the working perfused rat heart and a significant decrease in oxygen consumption [28, 41, 42]. Ketone bodies have been shown to increase cerebral blood flow and perfusion [95]. Also, ketone bodies have been shown to increase ATP synthesis and enhance the efficiency of ATP production [14, 28, 40]. It is possible that sustained ketosis results in enhanced cardiac efficiency and O2 consumption. Even though the size of the heart did not change for any of the ketone supplements, further analysis of tissues harvested from the ketone-supplemented rats will be needed to determine any morphological changes and to understand changes in organ size. It should be noted that the Harlan standard rodent chow 2018 is nutritionally complete and formulated with high-quality ingredients to optimize gestation, lactation, growth, and overall health of the animals. The same cannot be said for the standard American diet (SAD). Therefore, we plan to investigate the effects of ketone supplements administered with the SAD to determine if similar effects will be seen when the micronutrient deficiencies and macronutrient profile mimics what most Americans consume.
Alright, first of all, I tried every combination available for this product. I really loved the idea of adding it to my morning iced coffee with MCT, 1 tbs of heavy cream and stevia. To be honest, my morning coffee is one of my favorite things throughout my day and I was very dissppointed when it didn’t taste *exactly* like an iced mocha. I found it to be very bitter and tough to finish. Not to mention it was ruining my love for my morning coffee time.

Those of you who have tried this form of weight loss before are probably more than aware of how hard it can be to first get your body to adapt to such a dramatic change in your daily intake of food, let alone without the help of a single exogenous ketone supplement. And the situation isn’t made any easier if you use a poor quality ketosis supplement because the wrong ketone product may actually do you more harm than good.
Intellectual property covering uses of dietary ketone and ketone ester supplementation is owned by BTG Ltd., the University of Oxford, the National Institute of Health and TΔS Ltd. Should royalties ever accrue from these patents, KC and PC, as inventors, will receive a share of the royalties under the terms prescribed by the University of Oxford. KC is a director of TΔS Ltd., a company spun out of the University of Oxford to develop and commercialize products based on the science of ketone bodies in human nutrition. At the time of data collection and manuscript preparation, BS was an employee of TΔS Ltd., funded by the Royal Commission for the Exhibition of 1851. SH is an employee of NTT DOCOMO, Inc. (Japan). The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Yes. Both producing BHB in your liver as well as supplementing with beta hydroxybutyrate very safe. As we mentioned before, levels of 0.5 – 3.0 mmol measured in a blood test are completely normal. Some people get stressed out when they hear the term “diabetic ketoacidosis” or DKA, which is an entirely different metabolic scenario where your BHB levels skyrocket to 15-25 mmol blood readings.

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 process can be used as a way to get you into ketosis more quickly, so you can transition gracefully into a ketogenic lifestyle or as a way to stimulate autophagy and fat loss. If you can’t go without fat for the full 3 day fast — it’s okay — you will still illicit many of the benefits of fasting by limiting your protein and carbohydrate intake.
The liver is always producing ketones to some small degree and they are always present in the bloodstream. Under normal dietary conditions, ketone concentrations are simply too low to be of any significant benefit. A ketogenic diet and exogenous ketone supplements will increase the amount of ketone in your body. The idea that  ketones are “toxic” is ridiculous. Ketones are a normal physiological substance that play many important roles in the human body.
While ketone salts are widely available, unfortunately in the near-term ketone esters are in short supply and the only people who will be able to afford taking them several times per day will be elite athletes, the military, corporate CEO-types, and professional poker players. Even with economies of scale and ramping up production, the cost of raw materials to produce pure ketone esters will keep their price tag prohibitively high for most people, but could realistically get down to a few dollars per gram.
As Dr. Ryan Lowery pointed out to me, ketone supplements could play an important role in the future for elite sports performance, for example, or for people with brain injuries who cannot metabolize glucose properly. I am encouraged that scientists are working to develop these possibilities and, as long as plenty of peer-reviewed scientific research is done into the products being developed, I could feel more positive about the ketone salts in the future. For now, that scientific support is lacking.
I wrote this post at about the same time Germany won the World Cup in Rio de Janeiro in 2014. There’s been a lot of moving and shaking in the world of exogenous ketones since then, not to mention soccer. Looking back on my post, I still consider it relevant in terms of what exogenous ketones possibly can (and cannot) do for performance. In this case, to see if exogenous ketone esters provide me a “boost” by allowing me to do the same amount of work while expending less energy (and work at a relatively lower VO2) compared to no supplementation.

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