KBs can cross the BBB but not in a homogenous manner. For example, past experiments have demonstrated that BHB utilization is different in various brain areas (Hawkins and Biebuyck, 1979). Areas without BBB, hypothalamic regions and the lower cortical layers have a higher BHB metabolism compared to the lower one of the basal ganglia (Hawkins and Biebuyck, 1979). Also the metabolic meaning of the three KBs is different: while the main KB produced in the liver is AcAc, the primary circulating ketone is BHB. The third one, acetone, is produced by spontaneous decarboxylation of AcAc, and it is the cause of the classic “fruity breath.” Acetone does not have any metabolic functions, but it can be used as a clinical diagnostic marker. BHB acid is not, strictly speaking, a KB because the ketone moiety has been reduced to a hydroxyl group. Under normal conditions the production of free AcAc is negligible and this compound, transported via the blood stream, is easily metabolized by various tissues including skeletal muscles and the heart. In conditions of overproduction, AcAc accumulates above normal levels and a part is converted to the other two KBs. The presence of KBs in the blood and their elimination via urine causes ketonemia and ketonuria. Apart from being the fundamental energy supply for CNS, glucose is necessary for the replenishment of the quota of oxaloacetate, since this intermediate of the tricarboxylic acid cycle (TCA) is labile at body temperature and cannot be accumulated in the mitochondrial matrix. Hence it is necessary to refurnish the TCA with oxaloacetate via the anaplerotic cycle that derives it from glucose through ATP dependent carboxylation of pyruvic acid by pyruvate carboxylase (Jitrapakdee et al., 2006). This pathway is the only way to create oxaloacetate in mammals. Once produced by the liver, KBs are used by tissues as a source of energy (Fukao et al., 2004; Veech, 2004; McCue, 2010): initially BHB is converted back to AcAc that is subsequently transformed into Acetoacetyl-CoA that undergoes a reaction producing two molecules of Acetyl-CoA to be used in the Krebs cycle (Figure ​(Figure22).

The BBB, largely formed by the brain capillary endothelial cells, provides a protective barrier between the systemic blood and the extracellular environment of the CNS. Passage of FAs from the blood to the brain may occur either by diffusion or by proteins that facilitate their transport. Studies indicate that FATP-1 and FATP-4 are the predominant FA transport proteins expressed in the BBB based on human and mouse expression studies (Mitchell et al., 2011).

A review of multiple studies in the journal Nutrients found that ketogenic diets are connected to significant reductions in total cholesterol, increases in “good” HDL cholesterol levels, dips in triglycerides levels and decreases in “bad” LDL cholesterol; there are questions as to whether diets high in saturated fat negate these benefits. The same paper reports that a ketogenic may slightly reduce blood pressure, but science is still very scant on this point.
Hey guys, just started the Keto diet and needed some comfort food!! This recipe is the “BOMB”!!! Even my husband and his buddy loved it done up in a Romaine wrap. I have used also Norigami wraps, and made “cloud bread” to toast in a pan and top with the ooey gooey scrumptious Crack Chicken, if y’all haven’t tried this recipe DO IT!!! Keep um comin’ gals!!!!

Sarah, We’re sorry to hear that the burn warning came on when you made this! We updated the recipe above with the following note, which hopefully will help: We’ve tested this recipe upwards of 10 times and have never had the burn warning come on; however, several readers have had the warning come on, so we want to give a tip. In step 1 of the Instructions above, after removing the bacon from the pot, we recommend adding a splash of water, and use a wooden spoon to scrape up any brown bits that have formed on the bottom to deglaze the pan. After that, continue on with step 1 and press “Cancel” to stop sauteing.
Hi Maya. I LOVE your site!! Interesting, informative with fab recipes and ideas. Hubby and I have just started eating low carb and I have to say, we are not finding it too difficult and I already feel sooo much better!! I find the hardest part is choosing low carb veg, I feel as if we are not eating enough. Any suggestions on how to get more veggies into our diet?
A question we frequently get asked is whether you have to defrost boneless, skinless chicken breasts before making this recipe, or if you can just use them frozen. If you forgot to pull the chicken out of the freezer in the morning, we have good news for you! Crack Chicken can easily be made with frozen chicken. If using an Instant Pot, just add 5 minutes on to the cooking time (for a total of 20 minutes on Manual High Pressure).

It sounds like you have used ground/mince beef that was too fatty and the fat has rendered out into the casserole. I tend to avoid low fat beef as we want plenty of healthy fat to keep us fuller for longer and all the benefits that come from a high fat diet, but I also avoid the highest fat beef as too much fat comes out in the cooking process for a dish such as this one.


When you’ve eaten all of the crustless spinach quiche and keto frittata recipes that you can, these keto everything bagels are another great breakfast staple. With their help, you don’t have to cut out your favorite breakfast sandwiches. You can also try a bread-less keto breakfast sandwich with chicken sausage patties as the “buns” when you’re craving a keto-approved breakfast option.
While it may be new to you, the keto diet has actually been around since the 1920’s, when the Mayo Clinic reported its effectiveness for helping epilepsy (that is still the case). Since then, there’s strong evidence that the keto diet helps with weight loss as well as type 2 diabetes, prediabetes, and metabolic syndrome, says Jeff Volek, Ph.D., RD, professor in the department of Human Sciences at The Ohio State University in Columbus, Ohio and co-author of The Art and Science of Low Carbohydrate Living.
The SS providing information to the brain mainly send information to the nucleus of the solitary tract (NTS). These signals are generated in the GIT and abdominal viscera, as well as in the oral cavity and provide information about mechanical and chemical properties of food. The information is transmitted via vagal and spinal nerve to the NTS. The ASs arrive to the median eminence through ARC or through the blood-brain barrier (BBB). All these afferents are integrated in a complex and not fully understood network.
If you have a functioning pancreas that can produce insulin – i.e. you don’t have type 1 diabetes – it would be extremely hard or, most likely, impossible to get ketoacidosis even if you tried. That’s because high ketone levels result in release of insulin, that shuts down further ketone production. In other words, the body has a safety net that normally makes it impossible for healthy people to get ketoacidosis.
So our brains do require some glucose, and this is the main reason that registered dietitians (RDs) will tell you that carbohydrates are essential nutrients (meaning we have to eat them or we will die). But a biochemical fact check shows that this is not true. RDs neglect the research which shows that the brain can use ketones for over half of its fuel requirements once carbohydrate intake is lowered and ketone levels ramp up to full production. When ketones are available as a secondary fuel source, the brain requirement for glucose is lower, and the process of gluconeogenesis can make all the glucose the brain needs (about 50 grams/day). So although glucose is essential for the brain, eating carbohydrates to make glucose for the brain is NOT required. If you are have blood ketone levels above 1-3 mmol, the brain can use the ketones as an alternative fuel source.
Nutritional ketosis is a natural metabolic state in which your body adapts to burning fat rather than carbohydrates as its primary fuel. It is clinically proven to directly reduce blood sugar (as measured by HbA1c), improve insulin sensitivity (as measured by HOMA-IR) and reduce inflammation (as measured by white blood cell count and CRP). Nutritional ketosis can be induced by following a ketogenic diet. Learn more in our FAQ below!
Before we get started, here’s a short recap of the tips so far: The first and most crucial piece of advice was to choose a low-carb diet. The next were eating when hungry, eating real food, eating only when hungry, measuring progress wisely, being persistent, avoiding fruit, beer and artificial sweeteners, review your medications, stressing less and sleeping more, eating less dairy and nut products, stocking up on vitamins and minerals, using intermittent fasting and finally, exercising smart.
When you eat a ketogenic diet, you switch your body’s fuel source to fat rather than the body’s usual source, glucose (1). From this fuel source switch, the hunger hormone, Ghrelin, is reduced which causes your appetite to decrease (1). Because of the reduction in appetite, it is easier to adopt an intermittent fasting approach or an approach that lessons unwanted eating behavior outside your desired hours (AKA curbs the late night munchies). Therefore, I recommend eating 4 bigger meals rather than 6 small meals on a Ketogenic Meal Plan.
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