Being in optimal ketosis for a prolonged period of time (say, a month) will ensure that you experience the maximal hormonal effect from eating a low-carb diet. If this doesn’t result in noticeable weight loss, you can be certain that too many carbs are NOT part of your weight issue and not the obstacle to your weight loss. There are, in fact, other causes of obesity and being overweight. The next three tips in this series might help you.
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Thanks for all of the great info!! I have Hashimoto’s and would really like to try a high fat/low carb diet. You mentioned that this might not be a good option for people with thyroid issues. How do you recommend I modify my diet to lose weight taking into consideration the Hashimoto’s. I take Westhroid, a non-synthetic thyroid supplement to help with my sluggish thyroid. Thanks so much for any advice you can give me. :)

Thank you for this article as it cleared up a bunch of stuff for me. I started trying to get into ketosis back in August and lost 20lbs in about 6 weeks. Then it all stopped but had another 20lbs I wanted to loose. I had a hard time staying in ketosis and gave up about a week ago with the holidays approaching. Anyways I glazed over all the technical and science facts as it makes my head spin and might of missed it but my only question is what is the food portion of the diet like? The drinks are the easy part, do you have a diet plan that is good for someone that hits the gym hard 4-5 days a week for and hour and half. 45 min weights and 30-45 min cardio? It’s what I struggle with most the food and what attracted me to a ketogenic diet in the first place is eating 1 or 2 meals a day and being satisfied.
2) I have a hard time eating real food soon after rides/workouts. I had used Hammer Recoverite (1scoop instead of suggest serving of 2 and add 1scoop whey isolate protein) in the past because I feel a significant difference the day after with less muscle fatigue. Then I read a previous posts on your opinion of post-workout supplementation ( https://bengreenfieldfitness.com/2013/07/what-to-… ) and I realized the primary ingredient in Recoverite is maltodextrin. Since the 2013 article, has anything changed in your research that you might suggest I add PWO to aid in the muscle fatigue/recovery? (In other words, Is there anything more healthy I can take to replace the Recoverite or should the aminos/electrolytes/carbs/MCT’s from the recipe in this article be sufficient?) Thanks in advance, I appreciate all of your work!
Insulin is a hormone that lets your body use or store sugar as fuel. Ketogenic diets make you burn through this fuel quickly, so you don’t need to store it. This means your body needs -- and makes -- less insulin. Those lower levels may help protect you against some kinds of cancer or even slow the growth of cancer cells. More research is needed on this, though.
When you order here, you get 1560g unflavored Glycofuse – 3.4 pound with zero nasty additives or artificial sweeteners, at only 100 calories per serving. Just pure, clean-burning highly branched cluster dextrin for that slow bleed of carbohydrates you need to support energy for a long workout or race, or for the glycogen replenishment you need after a tough day at the gym, without getting massive fluctuations in blood sugar. 
I just discovered your site and have been thoroughly enjoying many of the articles and appreciate that you get so in depth in your explanations. I’m in my late 40’s and, while not an extreme endurance athlete, I am moderately active with 18-20 mile rides 3x a week as well as some boxing and body weight resistance (push up, pull up, etc) mixed in. I’ve generally been paleo and stick to quality macros for the most part (grass fed meats/dairy, organic veg and oils) and zero supplements. I recently started following keto (after reading this article) about 10 days ago and things seem good thus far. I do, however, want to avoid any of the negative side effects you mention and also not lose any lean muscle. I’m currently about 174 lbs, 5’8″ and about 19% bodyfat – I’m taking in about 95g protein, 130g fat and <20g net carbs. I'm eating all quality – wild salmon, grass fed beef, pastured eggs, coconut oil, Brain Octane and Grass fed butter in coffee, sardines, etc. With a smattering of organic veg, but it seems real easy to bust through the carb barrier. *I'M ALSO TAKING KETOCANA PRE-WORKOUT* and I notice this is keeping me going throughout a ride or the gym.
The ketogenic diet is calculated by a dietitian for each child. Age, weight, activity levels, culture, and food preferences all affect the meal plan. First, the energy requirements are set at 80–90% of the recommended daily amounts (RDA) for the child's age (the high-fat diet requires less energy to process than a typical high-carbohydrate diet). Highly active children or those with muscle spasticity require more food energy than this; immobile children require less. The ketogenic ratio of the diet compares the weight of fat to the combined weight of carbohydrate and protein. This is typically 4:1, but children who are younger than 18 months, older than 12 years, or who are obese may be started on a 3:1 ratio. Fat is energy-rich, with 9 kcal/g (38 kJ/g) compared to 4 kcal/g (17 kJ/g) for carbohydrate or protein, so portions on the ketogenic diet are smaller than normal. The quantity of fat in the diet can be calculated from the overall energy requirements and the chosen ketogenic ratio. Next, the protein levels are set to allow for growth and body maintenance, and are around 1 g protein for each kg of body weight. Lastly, the amount of carbohydrate is set according to what allowance is left while maintaining the chosen ratio. Any carbohydrate in medications or supplements must be subtracted from this allowance. The total daily amount of fat, protein, and carbohydrate is then evenly divided across the meals.[37]
After 2 years in ketosis suddenly I find my blood glucose has risen to high levels even while in ketosis. I thought it was the dawn phenomenon, stress hormones like cortisol but now I am beginning to think I am eating too many exongenous keytones like too much MCT oil? I am not taking exogenous keytone supplements but wondering if too much oil/ fat in the diet generates exogenous keytones which inhibits the livers production of endogenous keytones. I have read if the liver is producing endogenous keytones it is not at the same time producing glucose through gluconeogenisis?
The ketogenic diet achieved national media exposure in the US in October 1994, when NBC's Dateline television programme reported the case of Charlie Abrahams, son of Hollywood producer Jim Abrahams. The two-year-old suffered from epilepsy that had remained uncontrolled by mainstream and alternative therapies. Abrahams discovered a reference to the ketogenic diet in an epilepsy guide for parents and brought Charlie to John M. Freeman at Johns Hopkins Hospital, which had continued to offer the therapy. Under the diet, Charlie's epilepsy was rapidly controlled and his developmental progress resumed. This inspired Abrahams to create the Charlie Foundation to promote the diet and fund research.[10] A multicentre prospective study began in 1994, the results were presented to the American Epilepsy Society in 1996 and were published[17] in 1998. There followed an explosion of scientific interest in the diet. In 1997, Abrahams produced a TV movie, ...First Do No Harm, starring Meryl Streep, in which a young boy's intractable epilepsy is successfully treated by the ketogenic diet.[1]
Another difference between older and newer studies is that the type of patients treated with the ketogenic diet has changed over time. When first developed and used, the ketogenic diet was not a treatment of last resort; in contrast, the children in modern studies have already tried and failed a number of anticonvulsant drugs, so may be assumed to have more difficult-to-treat epilepsy. Early and modern studies also differ because the treatment protocol has changed. In older protocols, the diet was initiated with a prolonged fast, designed to lose 5–10% body weight, and heavily restricted the calorie intake. Concerns over child health and growth led to a relaxation of the diet's restrictions.[19] Fluid restriction was once a feature of the diet, but this led to increased risk of constipation and kidney stones, and is no longer considered beneficial.[18]
A lot of changes are happening in your body and you’re going to feel it! The first five to seven days can be pretty rough, but your body is getting over its dependency on sugar. During this time of transition it is essential that you supplement electrolytes. Your body is flushing out lots of water, and with that goes electrolytes. The Keto Flu can be greatly reduced if you add sodium, potassium and magnesium to your diet. Check out our supplements page for a list of electrolyte supplements we recommend. Stay on course and you’ll start feeling better in no time!
A small Feb. 20, 2017, study looked at the impact of a six-week ketogenic diet on physical fitness and body composition in 42 healthy adults. The study, published in the journal Nutrition & Metabolism, found a mildly negative impact on physical performance in terms of endurance capacity, peak power and faster exhaustion. Overall, researchers concluded, “Our findings lead us to assume that a [ketogenic diet] does not impact physical fitness in a clinically relevant manner that would impair activities of daily living and aerobic training.” The “significant” weight loss of about 4.4 pounds, on average, did not affect muscle mass or function.

But wait, there’s one loophole. Have polycystic ovary syndrome (PCOS)? Then the keto diet may help regulate your periods. “Women with PCOS have high insulin levels, which cause sex hormone imbalances,” notes Yawitz. In a small study published in the journal Nutrition & Metabolism, subjects with PCOS following a ketogenic diet for six months noted improvements in their menstrual cycles — and a small number of women became pregnant, overcoming previous infertility obstacles. “This study was very small, so we can’t make recommendations for all women with PCOS based on its findings,” says Yawitz. “And really, any diet that leads to weight loss should help in PCOS.”
Ideally, you combine supplemental ketones with a relatively low carb diet, especially if metabolic efficeincy is important to you. HOWEVER, you can achieve most of the benefits of ketosis aside from the fat burning efficiency by using exogenous ketones. So it all depends on how lean you are, what's important to you from a performance vs. fat loss standpoint, etc.
The presence of abnormally high levels of KETONES in the blood. These are produced when fats are used as fuel in the absence of carbohydrate or available protein as in DIABETES or starvation. Ketosis is dangerous because high levels make the blood abnormally acid and there is loss of water, sodium and potassium and a major biochemical upset with nausea, vomiting, abdominal pain, confusion, and, if the condition is not rapidly treated, coma and death. Mild ketosis also occurs in cases of excessive morning sickness in pregnancy.
Fascinating stuff and I am quite curious how we know for certain one is actually in ketosis i.e. using ketones as primary fuel source BECAUSE we do know that glucose has a shorter metabolic pathway to burn and under most conditions, given the presence of glucose, that is what the body will default to which is why high fat and high sugar together in diet is so detrimental. So if we use one or more of the above “boosters” and show high levels of blood ketones but also highish levels of glucose (during initial transition) will be mostly burning ketones or still defaulting to glucose?

Hi Ben great science & sound advice. May I share with the group? I’m 42, in australia, have been an alcoholic for 10 yrs. In April 2016 I gave up drinking & started living strictly ketogenic. In 3 months I dropped 25 kilos. I have cheated on weekends but I go through a fast of sorts on Mondays to get back into ketosis by Tues. I work afternoon / evenings so I wake at 10.30am take a pre workout drink with raspberry ketones & a splash of mct oil & all my vitamins as well. I then do weights for an hr then get ready to go to work. I take 2 800ml protein shakes consisting of 20 ml mct & 30grm amino enhanced protein. I work in warehousing so I walk anywhere between 10 km & 5 km a nite. I feel great all the time, thanks largely to your research & advice. If have any thoughts or opinions I’d love hear them.
It seems strange that a diet that calls for more fat can raise “good” cholesterol and lower “bad” cholesterol, but ketogenic diets are linked to just that. It may be because the lower levels of insulin that result from these diets can stop your body from making more cholesterol. That means you’re less likely to have high blood pressure, hardened arteries, heart failure, and other heart conditions. It's unclear, however; how long these effects last.
But while carbohydrates can help you have a better workout, go faster, or go longer, this only applies to acute, in-the-moment performance. Once you take a look (which you’re about to do) at the long-term effects of chronic high blood sugar levels, things change drastically. If the damage that you’re above to discover is worth it to you, then you are either mildly masochistic or you value performance much more than health.
Hi Ben, I have a question about being in ketosis. So from what I understand, a serving of Keto os will keep you in ketosis for about 4-6 hours or so……my question is doesn’t your body have to be in constant ketosis in order to really experience the benefits of using the fat as fuel? Also, if someone is not following the Keto diet, what happens to the glucose they are still consuming if they are supposedly using ketones for energy? Also, do you see any benefit from using Keto os vs. Brain Octane? I ask because there is a significant difference in price. Thank you so much!!
I talk about that quite a bit here :https://bengreenfieldfitness.com/2015/09/things-your-pee-can-tell-you-about-your-body/
Ketosis is an option for many people with type 2 diabetes because they still produce insulin, which helps their body maintain a safe level of ketones in the blood. If you’re considering trying ketosis or the ketogenic diet with type 2 diabetes, be sure to consult your healthcare provider first to ensure it’s safe for you. This eating approach may interfere with some types of diabetes medication or be inappropriate for you if you have certain diabetes complications, such as kidney damage.

What are the ideal levels of blood sugar? A blood sugar or blood glucose chart identifies ideal levels throughout the day, especially before and after meals. The charts allow doctors to set targets and monitor diabetes treatment, and they help people with diabetes to self-assess. Learn more about guidelines, interpreting results, and monitoring levels here. Read now
Ketosis is the metabolic process of using fat as the primary source of energy instead of carbohydrates. This means your body is directly breaking down its fat stores as energy instead of slowly converting fat and muscle cells into glucose for energy. You enter ketosis when your body doesn’t have enough glucose (carbohydrates) available. The prime function of the ketogenic diet is to put the body in ketosis.

It seems strange that a diet that calls for more fat can raise “good” cholesterol and lower “bad” cholesterol, but ketogenic diets are linked to just that. It may be because the lower levels of insulin that result from these diets can stop your body from making more cholesterol. That means you’re less likely to have high blood pressure, hardened arteries, heart failure, and other heart conditions. It's unclear, however; how long these effects last.

Hi Ben – Great article. I had trouble at the end figuring out if you were now eating high fat (60-80% of calories), or if you went back to something closer to 50% fat calories and higher carbs and are using exogenous ketones to get int ketosis when needed. Are you doing any carbs at night or a refeed, or just having higher carbs on most days? Thanks
To encourage ketone production, the amount of insulin in your bloodstream must be low. The lower your insulin, the higher your ketone production. And when you have a well-controlled, sufficiently large amount of ketones in your blood, it’s basically proof that your insulin is very low – and therefore, that you’re enjoying the maximum effect of your low-carbohydrate diet. That’s what’s called optimal ketosis.
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