Exercise, particularly high-intensity exercise, tends to speed up the transition phase because it helps deplete glycogen stores quickly, forcing the body to rely more on fat. Additionally, starting the transition with fasting or intermittent fasting can rapidly increase ketone production.
The ill feeling that may occur in the first few days after initiating a ketogenic diet is commonly referred to as the keto flu. Fortunately, this feeling is temporary and can be completely or partially alleviated by following a few precautionary measures. First, consider your electrolytes. A deficiency in sodium, potassium, or calcium could make you feel sick. Second, consider your hydration level. It’s easy to get dehydrated at the beginning of the ketogenic diet. Third, consider your fiber intake. If you’re not getting enough fiber, you could become constipated. The takeaway: replenish your electrolytes, drink a lot of water, and make sure you’re getting enough fiber.
This is difficult to say; it depends on the reason for ketosis. As long as ketone levels are greater than 0.5 mmol, you’re in ketosis. Many people think that higher ketone levels are better, but this has yet to be established. Some individuals who have been keto-adapted for an extended period may become particularly efficient at using ketones and therefore don’t have a lot of them circulating in the blood. For some health concerns, such as epilepsy and other neurological conditions, higher ketone levels may be beneficial—exogenous ketones or high-dose MCT may be especially helpful in order to accomplish those levels.
Taking ketone supplements without lowering carbohydrate intake will not likely make you fully keto-adapted. It is unknown whether taking these supplements long-term can lead to certain changes that typically occur with keto-adaptation (such as an enhanced capacity to allow ketones to enter tissues to be used for fuel by increasing the number of ketone transporter proteins), but in order to be fully keto-adapted, some degree of carbohydrate restriction needs to occur.
The keto flu is a constellation of symptoms that can occur when you’re adjusting to a ketogenic diet. Symptoms include a lack of mental clarity, nausea, headaches, and constipation. A well-formulated ketogenic diet that takes into account electrolytes, fiber, and hydration can help mitigate these symptoms.
You can test your ketone levels using urine strips, blood ketone meters, and breath ketone meters. Blood meters, which test for BHB, are considered the gold standard. Breath analysis has been shown to be effective at measuring acetone, while urine analysis measures acetoacetate. Urine strips can provide good feedback at the beginning of the diet, but once you’re keto-adapted and using ketones more efficiently, fewer ketones are expelled in the urine, so they are not a reliable indicator of degree of ketosis.
When you’re keto-adapted, your body has transitioned from primarily using glucose as fuel to primarily using fat and ketones. Once accomplished, you will start to see a change in satiety, hunger, and even cognitive function/focus.
Ketosis is generally recognized to occur when ketone levels rise to 0.5 mmol. Two days of carbohydrate restriction can be enough to reach this level. However, achieving this level of ketosis does not mean that you are keto-adapted—that your body is primarily using fat as fuel. Becoming fully keto-adapted may take longer; exactly how long varies from person to person.
Exogenous ketone esters have been found to be safe in humans and animals. Additionally, ketone salts have been granted GRAS (generally recognized as safe) status. Several studies have used both ketone salts and ketone esters in both animals and humans with no adverse side effects. A recent study in 2020 showed no adverse effects on consuming over 25 grams of ketone salts daily for 90 days in healthy adults.
Yes! No adverse effects were found in people taking 30 grams of MCTs a day (much higher than typically consumed) for thirty days. Additionally, 1 gram of MCT per kilogram of body weight has been established as safe. However, MCTs can have gastrointestinal side effects, such as nausea and diarrhea, so we highly recommend starting slow and building your way up to see how much you can tolerate.
No. MCTs can be converted into ketones once they’re broken down in the liver . However, some research suggests that it takes extremely high amounts of MCT (more than 20 grams) to get the same effects that just a couple grams of exogenous ketones could achieve.
Exogenous ketones likely do not cause fat loss directly. Keep in mind that they are an energy source and do have calories. However, having elevated ketone levels has been shown to reduce hunger, increase the production of new mitochondria, and decrease the ratio of weight gained to amount of food consumed , which could allow for greater fat burning and incidentally reduce body weight.
Check out our entire Ketone Resource Section here:
Exogenous ketones are supplemental ketones that are found in either powdered or liquid form. The powdered versions are bound to minerals such as calcium, sodium, or magnesium, while the liquid forms primarily consist of ketone esters. Exogenous (outside) ketones are ketones that are ingested and, upon consumption, behave similarly to the endogenous ketones that the body produces due to carbohydrate restriction.
Check out our entire KetoClass on exogenous ketones here.
Saturated fat should not be demonized, especially on a ketogenic diet. However, we have found that our bodies adapt best when saturated fat represents about 50 percent of our total fat intake and the rest comes from monounsaturated fats like oils and avocados. This could, in part, explain why so many studies have different findings in regards to cholesterol and triglyceride levels following a ketogenic diet . If you are concerned about these factors, ensuring that you consume a balance of saturated and monounsaturated fats may be a good approach for you.
When you are keto-adapted, you become much more efficient at utilizing fat as fuel, and some studies show that slightly overfeeding on fat alone may not cause significant weight gain. However, keep in mind that fat is calorically dense, with 9 calories per gram. Eating excessive amounts of fat can increase calories to an extent that may prevent certain benefits from occurring, such as fat loss. Supplying your body with too much dietary fat may keep it from breaking down your own fat stores for energy. As with everything, keep the fat content of the diet in context, and don’t binge on fat bombs.
While we love fat, it is important to note that not all fat is created equal. Omega-6 fatty acids are known for contributing to inflammation, which is associated with many chronic diseases. Make sure to balance your omega-3 fatty acids with your omega-6 fatty acids to ensure the best overall outcome. Trans fats are harmful to health and should be limited. If you hit a plateau or obstacle throughout your time on a ketogenic diet, we have found that lowering dairy fat and saturated fat as a whole slightly while increasing your unsaturated fats can help.
We do not intend to demonize carbohydrates as the sole culprit for the obesity epidemic we are facing. Instead, we hope to change the paradigm of a “healthy” diet model to help people look at carbohydrates as a useful tool rather than a dietary necessity. Although, it is true that chronic high carbohydrate consumption can lead to chronic high blood glucose and insulin levels, resulting in metabolic changes such as insulin resistance that increase the likelihood of becoming obese, it is possible for many people to consume carbohydrates and maintain a healthy profile.
While some amino acids, such as leucine and lysine, can be converted to ketones, others can be converted into glucose and may therefore raise blood glucose and insulin levels if consumed in excessive amounts. For this reason, we suggest consuming no more than 20 to 35 percent of your calories from protein. Keep in mind that the optimal level varies from individual to individual—for instance, someone using a ketogenic diet to help with epilepsy may need less protein than someone using it to try to gain high amounts of muscle mass.
It’s common to reduce fiber intake when switching to a ketogenic diet, simply because fiber is most abundant in foods that are high in carbohydrates, particularly vegetables and grains. Fiber is an important nutrient that’s essential for good health, and although it is technically a carbohydrate, it does not increase blood glucose or insulin levels. So we highly recommend making an effort to get enough fiber unless you are on a carnivore or low fiber diet, in which the approach is slightly different.
Potassium, magnesium, and calcium also can become depleted on a ketogenic diet.
Sodium levels do drop on a ketogenic diet, so it’s a good idea to consume more sodium. Real Salt can be a great, beneficial source because it contains many minerals, including sodium, calcium, potassium, iodine, and magnesium, with a sodium content similar to table salt but with larger crystals for more flavor.
Studies suggest that the body does not require carbohydrates to replenish glycogen , and research in keto-adapted athletes has found that they spare and replenish muscle glycogen at similar rates as carbohydrate-adapted athletes . At the beginning of a ketogenic diet, as your body is adapting to burning fat, glycogen stores may be limited, but they soon rebound once you’re fully adapted.
A target macronutrient ratio can be a good place to start, but keep in mind that the macros that work best for you and your lifestyle may differ from what works for someone else. The key is to keep carbohydrate intake low, protein moderate, and fat moderate to high. Have fun with it and tinker with your diet until you figure out what is optimal for you. Once you have individualized the diet to work best for you, and after you have been on it for a while, you will learn what you should and shouldn’t eat to maintain your optimal ratio, and therefore you may not need to count macronutrient content as strictly.
When you first start following a ketogenic diet, we recommend tracking macronutrients and calories just to get the hang of it and to make sure that you’re getting the right amount of each. However, soon after adapting, you should simply be able to eat until you are full while monitoring your carbohydrate intake. Don’t let those sneaky carbohydrates creep up too high. In fact, people who are keto-adapted often reduce their calories unintentionally simply because they feel full faster. If possible, eat to satiety once you get the hang of it; your keto-adapted appetite should ensure that you consume enough calories without overeating. Those using the diet for therapeutic application should incorporate some level of calorie control/restriction in order to receive the best results from the diet.
For a reference on where to start in terms of calorie needs, check out our calculator here.
If using a well-formulated ketogenic diet, then no; not only is the high amount of fat on a ketogenic diet satiating, but ketones also seem to reduce hunger signals. Studies have allowed subjects on a ketogenic diet to eat as much as they want, yet they still tend to eat fewer calories, report less hunger, and lose more weight than those on a non-ketogenic diet . It is possible that this is because fat is more calorically dense; however, studies have also demonstrated that being in a state of ketosis can reduce hunger signals.
Nutritional ketosis is characterized by a controlled increase in ketones, along with reductions in blood glucose and normal blood pH. Ketoacidosis is characterized by the uncontrolled increase in ketone production (higher than 15 mmol) despite elevated blood glucose levels and results in dangerous decreases in blood pH ; this is mainly a concern for type 1 diabetics. Ketogenic diets and ketone supplementation typically do not raise ketone levels past 5 to 7 mmol.
Although both Atkins and a ketogenic diet feature similar levels of carbohydrate restriction, the two differ in protein and fat intake. The Atkins diet typically allows individuals unrestricted protein intake. However, on a ketogenic diet, protein intake tends to be around 10 to 30 percent to allow for the production of ketones.
There’s no strict definition of “low carb.” Some studies suggest that a low-carb diet is any diet with less than 30 percent of calories coming from carbohydrates . A ketogenic diet generally restricts carbohydrates further, to as low as 5 percent of total calories. So while a ketogenic diet is certainly low-carb, not all low-carb diets are ketogenic. The greater restriction of carbohydrates on a ketogenic diet results in the production of ketones.
Yes, when properly formulated, the ketogenic diet is safe. If any of the following affect you, a ketogenic diet may not be right for you—talk to your doctor.
Ketones can be used by nearly all of the cells and tissues in the body, though not used by the liver (where they are made). Some cells, like those in certain regions of the brain and red blood cells, can use only glucose for energy, but the amount of glucose the body can produce from gluconeogenesis is plenty to provide those cells with what they need when carbohydrate consumption is low.
Unlike most fatty acids, ketones can be taken in and used as an energy source for the brain. In fact, the brain may actually prefer ketones to glucose; studies have shown that ketone uptake by the brain increases as blood ketone levels rise . There is also a lot of research demonstrating that a ketogenic diet can have brain-protecting effects in various types of damaged neurons, possibly due to the neurons receiving greater fuel reserves through ketones, less oxidative stress, and less inflammation . Even when glucose uptake by the brain is impaired, as it is in people with Alzheimer’s, traumatic brain injury, and Parkinson’s, ketones can still be utilized.
Ketones are produced during the breakdown of fat by the liver. Fat is primarily broken down for fuel when carbohydrate consumption (and insulin) is low.
Below are actions to consider taking to continue losing fat:
There are plenty of studies demonstrating improvements in body composition (i.e., reduced fat mass and maintained or increased lean muscle mass) and blood lipids (i.e., reduced triglyceride and total cholesterol levels and increased HDL cholesterol levels) on a ketogenic diet without exercise . However, exercise is a key component of a healthy lifestyle and can dramatically improve your results on a ketogenic diet. For this reason, we highly recommend some type of physical activity or exercise on a ketogenic diet, even if it is just walking ten thousand steps per day (about 5 miles). Additionally, research shows that even moderate walking increased brain ketone uptake so get get out and move.
Ketogenic.com suggests tracking total carbohydrates (fiber + non-fiber carbohydrates) in the initial stages of “keto-adaptation;” however, once adapted, one may be able to track “net” carbs (non-fiber carbohydrates – fiber).
For more information on the difference between total and net carbohydrates check out this article here.
In most cases, a carbohydrate refeed is not necessary on a ketogenic diet, as the keto-adapted biological and metabolic changes do not require dietary carbohydrates. There are certain circumstances, however, in which an increase in small carbohydrate influx may be beneficial (i.e. high intensity activity/sports or even during a menstrual cycle for females); however, more research is needed on this topic, specifically with respect to variations of ketogenic diet including “cyclic” and “targeted” ketogenic diets.
One of the many benefits of being in a ketogenic state is muscle preservation. Research has demonstrated that ketones prevent muscle catabolism/breakdown. Furthermore, recent research also suggests that ketones may actually help with muscle anabolism/building muscle anabolism as well. For these reasons alone, eating a well formulated ketogenic diet with adequate amounts of protein would still allow you to maintain or even increase muscle mass.
At first, you may experience hunger while your body adapts to switching from primarily running on carbohydrates/glucose to fat/ketones. However, if your diet is well formulated, hunger tends to subside once you are adapted and your ketones become elevated and your blood glucose stabilizes.
MCTs are fatty acids that are structurally shorter than long-chain triglycerides (LCTs). While LCT’s require processing from the gallbladder, MCTs are rapidly digested and directly used for energy, with a lower propensity for fat storage. These fats are a staple on the ketogenic diet and can be easily converted to ketones!