Another effect of the ketone drinks was to lower blood glucose, free fatty acids, and triglyceride levels. This sounds great. Elevated levels of all those markers are harbingers of disease, particularly if they remain chronically elevated. But think about what this means. If free fatty acids go down, that means adipose tissue isn’t being liberated for burning.
If the goal is to deplete glucose levels so that we can start producing ketone bodies, then forcibly exerting physical energy through exercise is a great way to go about it. Keeping it relatively low intensity to begin with and working out in the morning is recommended as this helps to keep down your cortisol (stress hormone) levels. This only applies at the beginning of your keto adaptation process, as intense workouts such as HIIT once already keto-adapted will be completely fine.

Hello! I’m planning on taking a short vacation and will be having “kept friendly” drinks, mostly vodka and water with lemon and stevia. When should I take my exogenous ketones? That night before bed or early the next morning or after the 3 day vacation is completely over? I’m unsure how to manage this to have the best odds of staying in ketosis and get back to burning FAT. Also, I just purchased Instaketones from Julian Bakery, what are your thoughts on this brand? Thanks for what you do!
We demonstrated that therapeutic ketosis could be induced without dietary (calorie or carbohydrate) restriction and that this acute elevation in blood ketones was significantly correlated with a reduction in blood glucose (Figs. 2, ​,33 and ​and4).4). The BMS ketone supplement did not significantly induce blood hyperketonemia or reduced glucose in the rats. The KE supplemented rats trended towards reduced glucose levels; however, the lower dose of this agent did not lower glucose significantly, as reported previously in acute response of mice [59]. MCTs have previously been shown to elicit a slight hypoglycemic effect by enhancing glucose utilization in both diabetic and non-diabetic patients [86–88]. Kashiwaya et al. demonstrated that both blood glucose and blood insulin decreased by approximately 50 % in rats fed a diet where 30 % of calories from starch were replaced with ketone esters for 14 days, suggesting that ketone supplementation increases insulin sensitivity or reduced hepatic glucose output [89]. This ketone-induced hypoglycemic effect has been previously reported in humans with IV infusions of ketone bodies [90, 91]. Recently, Mikkelsen et al. showed that a small increase in βHB concentration decreases glucose production by 14 % in post-absorptive health males [92]. However, this has not been previously reported with any of the oral exogenous ketone supplements we studied. Ketones are an efficient and sufficient energy substrate for the brain, and will therefore prevent side effects of hypoglycemia when blood levels are elevated and the patient is keto-adapted. This was most famously demonstrated by Owen et al. in 1967 wherein keto-adapted patients (starvation induced therapeutic ketosis) were given 20 IU of insulin. The blood glucose of fasted patients dropped to 1–2 mM, but they exhibited no hypoglycemic symptoms due to brain utilization of ketones for energy [93]. Therefore, ketones maintain brain metabolism and are neuroprotective during severe hypoglycemia. The rats in the MCT group had a correlation of blood ketone and glucose levels at week 4, whereas the combination of BMS + MCT produced a significant hypoglycemic correlation both at baseline and at week 4. No hypoglycemic symptoms were observed in the rats during this study. Insulin levels were not measured in this study; however, future ketone supplementation studies should measure the effects of exogenous ketones on insulin sensitivity with a glucose tolerance test. An increase in insulin sensitivity in combination with our observed hypoglycemic effect has potential therapy implications for glycemic control in T2D [40]. Furthermore, it should be noted that the KE metabolizes to both AcAc and βHB in 1:1 ratio [29]. The ketone monitor used in this study only measures βHB as levels of AcAc are more difficult to measure due to spontaneous decarboxylation to acetone; therefore, the total ketone levels (βHB + AcAc) measured were likely higher, specifically for the KE [14]. Interestingly, the 10 g/kg dose produced a delayed blood βHB peak for ketone supplements MCT and BMS + MCT. The higher dose of the ketogenic supplements elevated blood levels more substantially, and thus reached their maximum blood concentration later due to prolonged metabolic clearance. It must be noted that the dosage used in this study does not translate to human patients, since the metabolic physiology of rats is considerably higher. Future studies will be needed to determine optimal dosing for human patients.
Possible GI distress (flatulence) at exceptionally high doses –  In the studies referenced in this article, exogenous ketones taken in large doses occasionally resulted in GI distress, especially flatulence. However, the cause of this is hypothesized to be due to the fact that ketones were mixed in a milky fluid that wasn’t very palatable. If you’re taking a nominal dose of exogenous ketones the likelihood of GI distress is rather low. Moreover, if some GI distress is prevalent, it should improve as you become accustomed to taking ketones.
At baseline, 4 h after intragastric gavage, the elevation of blood ketones was inversely related to the reduction of blood glucose compared to controls following the administration of MCT (5 g/kg) (p = 0.008) and BMS + MCT (5 g/kg) (p = 0.039) . There was no significant correlation between blood ketone levels and blood glucose levels compared to controls for any other ketone supplemented group at baseline (Fig. 4a). At week 4, 4 h after intragastric gavage, there was a significant correlation between blood ketone levels and blood glucose levels compared to controls in MCT (10 g/kg) and BMS + MCT (10 g/kg) (p < 0.0001, p < 0.0001) (Fig. 4b).
There are a couple factors that will make this look much more viable and achievable. For example, if you were to skip breakfast and have your first meal at 12PM, you could eat up until 8PM. This will also mean that dinner needs to be eaten slightly earlier. But let’s not forget about the fact that if we were to combine this with the 6-10 hours of sleep that you would normally have each night, that’ll take up the majority of your fasting period. Obviously, you’re not restricted to these hours, as everyone has a different schedule. Doesn’t sound as bad as you initially thought? Well let’s make it even more enticing! During your fasting hours, and this is extremely helpful during mornings up until you can have your first meal, non-caloric beverages such as tea and coffee can help starve away those hung pangs. Just make sure you’re taking these drinks on it’s own, without any added sugar or milk. There are many variations of intermittent fasting with the most common being 16/8. But depending on your schedule, there are other options advocated such as 20/4, 22/2, and if you’re crazy enough and can eat a full day’s worth of calories in one sitting then there is also OMAD (one meal a day).
Most of the ketone supplements out there are either underdosed or overpriced - some don't even bother to disclose how much BHB (ie ketones) is used in their product. And why would they? BHB is EXTREMELY expensive. So by not disclosing the amount the can get away with putting in as little as they want and still claim it's a ketone supplement while keeping their costs as low as possible.
We’ve all been taught that high sodium intake is bad for us, similar to how we’ve been told for decades that fat is the driver of coronary heart disease, and consuming large amounts will kill us.  Sodium has been thought to increase blood pressure, and therefore increase the risk of heart disease, kidney disease, stroke, osteoporosis, and stomach cancer. Thus, many of us tend to avoid consuming foods or supplements with labels that have high amounts of sodium.
Too much cortisol tells the liver that you are in physical danger and need a lot of energy fast. The brain doesn't understand the difference between physical danger and emotional stress. When emotionally stressed, the brain thinks you're in a life-and-death situation, so the liver comes to your rescue and gives you the glucose you need to fight off your attacker.
Exogenous ketones don’t seem to improve high-intensity, glucose-intensive exercise, increasing fat burning during steady state exercise but dropping top-end high-intensity performance. Another study found that ketone dieters reduced 50-minute time trial performance in cyclists, though another group of researchers have criticized the methods. Even when a ketone ester didn’t improve performance in the shuttle run to exhaustion and 15 meter sprint repeats, it did reduce the drop in brain function following the exercise.
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.
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).

How to get into ketosis in 24 hours you ask? Can it be done? Yes, it can happen. But only for people who have already been keto-adapted and may have dropped out of ketosis for a short period of time, like after a cheat day. Those people can follow these steps to get back into ketosis quickly. However, if you are just starting keto you have a lot of work to do before your body will let you get into ketosis.
Now that you have fasted for quite a long time, you can break your fast at around 4 to 5 pm. Try having some good fat for this purpose, such as coconut oil or MCT oil, butter, or any other healthy fat. MCT oil might come in as a better option in this case since it gets quickly absorbed by the body. It swiftly bypasses the gallbladder and reaches the liver where it is transformed to ketones rapidly.

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.
I don’t recommend that you go straight for a 1-2 day fast, but begin by restricting yourself to certain eating windows. Typically people restrict themselves to the hours of 5pm – 11pm. People often refer to their fasting windows by numbers: 19/5 or 21/3, for example, means 19 hours of fasting and 5 hours eating or 21 hours fasting and 3 hours eating, respectively.
If you do the same calculations as I did above for estimating fat oxidation, you’ll see that EE in this case was approximately 13.92 kcal/min, while fat oxidation was only 67% of this, or 9.28 kcal/min, or 1.03 g/min. So, for this second effort (the test set) my body did about 5% less mechanical work, while oxidizing about 25% less of my own fat. The majority of this difference, I assume, is from the utilization of the exogenous BHB, and not glucose (again, I will address below what I think is happening with glucose levels).

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