Dr. Campos, it is unfortunate that you retain the medical community’s negative stance on the ketogenic diet, probably picked up in medical school when you studied ketoacidosis, in the midst of an obesity and type II diabetes epidemic that is growing every year, especially among populations who will never see the Harvard Health Letter. The medical community has failed in reversing this trend, especially among children, and the public is picking up the tab, in the form of higher health insurance premiums to treat chronic metabolic diseases which doctors cannot cure. The ketogenic diet does not bid its adherents to eat unhealthy processed meats, and the green leafy vegetables that it emphasizes are important in a number of nutritional deficiencies. People lose weight on the ketogenic diet, they lose their craving for sugar, they feel more satiety, they may become less depressed, their insulin receptors sensitivity is improved, and these are all the good outcomes you fail to mention. There is a growing body of research which demonstrates the neuroprotective effects of the ketogenic diet to slow cancer progression, as well as diseases like Parkinson’s and Alzheimer’s, for which there are no effective medical treatments. Please respect your patients by providing them with evidence-based medical outcomes, not opinions.

Traditionally, in the sports nutrition field, we talk about the importance of timing carbohydrate and fluid intake on improving sports performance. For some time now, research has been looking at the role of very low carbohydrate diets on sports performance. Trailblazers in keto and sports performance research like Dr. Stephen Phinney have been conducting studies in this area since the 80s. In one of his studies, the glycogen stores of cyclists on a keto diet were not completely depleted and lipid oxidation was increased. Researchers concluded that the body was able to adapt to the lack of carbohydrates and preserve what was needed to use the fat as fuel.  However, based on the VO2 max breath test, since the body was attempting to preserve the carbohydrate during the exercise, it appears that the intensity of the exercise was limited. In a more recent study, off-road cyclists following a keto diet experienced small improvements, but still not significant enough to make strong conclusions.


We have solid evidence showing that a ketogenic diet reduces seizures in children, sometimes as effectively as medication. Because of these neuroprotective effects, questions have been raised about the possible benefits for other brain disorders such as Parkinson’s, Alzheimer’s, multiple sclerosis, sleep disorders, autism, and even brain cancer. However, there are no human studies to support recommending ketosis to treat these conditions.
To minimize the risk of hypoglycemia, Yancy and his team decrease medication as soon as a patient starts the diet. While drugs like metformin and liraglutide (Victoza) are less of a concern, there are others that pose a substantial hypoglycemia threat. In addition to insulin, the sulfonylurea drugs glipizide and glyburide require a watchful eye, as they work by stimulating the pancreas to make more insulin, increasing the risk of dangerous lows in the face of insufficient carbohydrate intake. “People on this diet need to be prepared to check their blood glucose any time they feel like it could be getting too low,” says Urbanski. “I would say a minimum of twice a day, but ideally three to four times a day, at least in the beginning in order to see the effect of the diet on their blood glucose readings.”
The longer you’re in ketosis, the more fat you burn. Unfortunately, you may also start to lose muscle tissue, too. While protein is considered the powerhouse muscle builder, your muscles need carbs for adequate formation and maintenance. Without those carbs, your body may start breaking down muscle. “Since your body starts to eat away at muscles as it enters ketosis, your heart, being a muscle, may also be damaged in the process,” Derocha says.
"Most people who wind up trying a ketogenic diet and then deciding not to continue do so because of the emotional and lifestyle consequences," Turoff says. To put it simply, people miss eating carbohydrates. "That doesn't mean that you should be eating pizza or cupcakes every day, but what about having a sweet potato with a meal, or beans in a chili? Or fresh watermelon in the summer?" Turoff asks. "Whether or not we want to admit it, food plays much more than just a physical role in our lives and having such restrictions on the types of foods you can and can't eat can really take a toll. It might be easy in the short-term to go for carb-free foods but at a certain point, the thought of not being able to eat your favorite foods again can become daunting."

Ketosis is different, because, when in the state of ketosis, the brain will prefer ketones over glucose. For the dieter this is good! The body will not have to break down protein for energy. In turn the body will be forced to use its fat reserves, a.k.a. your love handles, for its energy. This is why a low-carb diet is such a good method of dieting.


And, it's important to recognize that both study teams acknowledge that as exciting as their findings seem, a large, randomized controlled trial is still needed to more closely assess a variety of components that may be contributing to the successes found in both studies before the findings can be recommended to anyone outside the study groups1,2  he says.
She has found that when women stick to eating a lighter dinner, and then abstain from eating for about 13–15 hours between dinner and breakfast, they experience improvements in their weight, blood sugar control, etc. She recommends that women try avoiding eating after 8 p.m. or experiment with eating only two meals per day, with tea or broth between meals to help curb hunger. Another option is to try skipping dinner altogether on 1–2 days per week. For most women, when attempting IMF, it’s not recommended to snack between meals unless the woman is very active (such as an athlete in training) or dealing with a hormonal issue such as adrenal burnout.
There are various ways to practice intermittent fasting on keto, including some that are less likely to trigger side effects like fatigue or cravings. Crescendo fasting gives you a break from fasting throughout your week, but is still very helpful for achieving the benefits of IMF. Dr. Cabeca and other experts, such as Amy Shah, M.D., advise their patients to check their urinary ketone levels (using ketone strips) and to aim for testing positively for ketones about three days per week.
As for individuals with type 2 diabetes, Dr. Galati says, "a very low carbohydrate diet could be tolerated, albeit with extreme caution. Transitioning to a ketogenic diet will require several lifestyle changes as well as careful monitoring of both your food intake and glucose levels and adjustments to your medications. Also, you should increase your water consumption." 

3. Ketone bodies are NOT a better source of energy than glucose. Your body uses SO much more energy just to MAKE ketone bodies. Basically, your cells take in fats and turn these into Acetyl CoA in the mitochondria. In a NORMAL cell, this acetyl CoA would go through the Citric Acid Cycle and onto the Electron Transport Chain, making energy that can be used by ALL of your cells. ( In a cell that is in the state of Ketosis (AKA Starvation), the acetyl CoA is not used for the citric acid cycle, but is instead used to make the ketone bodies. The ketone bodies then make their way to the brain. Not to mention, gluconeogenesis is also occurring (at depleted rates at this point …. you know, because you’re running out of those scary glycogens.) And remember, gluconeogenesis is also energetically expensive, along with the production of ketone bodies. So all in all, you are losing energy by resorting to Ketosis.


Restricting carbohydrates.  Studies show that after three or four days without carbohydrate consumption, your body starts tapping its fat storage also known as ketosis. You’ll want to stay between 25–35 grams of carbs to get into ketosis, and that requires bucking mainstream, carb-heavy, and supposedly nutrient-rich foods like fruit and grains. There are good carbs you can eat that will help you stay in ketosis. Be sure to look over these more keto diet friendly fruit options.
Coal, on the other hand, burns evenly, and continues to burn for hours. Not only that, but it is fairly simple to adjust the amount of coal you burn to keep the house nice and warm, but not hot, for extended periods of time. The only problem is, it is kind of a hassle to get it to start burning at first (again, in the analogy we are assuming you are simply trying to light bare coal on fire, no aids). But once it is started, maintaining it is no sweat. So what is the solution? You use a tiny bit of kerosene, which lights easy and burns hot, to get the coals started (we need a few carbs, but not much).
In another study on women, researchers confirmed that the ketogenic diet resulted in favorable changes in LDL particles consistent with lower cardiovascular disease risk. However, the total LDL cholesterol did not change. This is why it is important to test the levels of different LDL particles. Looking at the LDL number itself may be misleading, especially on the ketogenic diet.

Those with mental health conditions have higher rates of physical illness and premature mortality, with life spans shortened by 13 to 30 years. People with mental health conditions also have higher rates and worse outcomes for chronic conditions such as diabetes, cardiovascular disease, and cancer. Years lived with disability for mental and substance use disorders increased 45% from 1990 to 2013 worldwide – during the same time that the incidence of obesity and the diabetes exploded.


Maria Emmerich: I struggled with my weight most of my life. I tried exactly what I was told to do – eating low fat and working out more and more. I even got to where I ran a marathon and still ended up gaining weight! I knew there had to be another way. I spent years researching all the latest science, and that led me to a ketogenic lifestyle and I have never looked back. I cured my irritable bowel syndrome (IBS), acid reflux and polycystic ovary syndrome (PCOS) and lost the extra pounds.
While sugar may be a great quick form of energy, it doesn’t keep your brain at its best. “There is a lot of evidence coming out which suggests that the brain operates more efficiently on ketones than it does on blood sugar, but the research is all fairly new,” Olin says. “Ketones are made to fuel the brain in the absence of glucose,” says Kristen Mancinelli, a registered dietitian and author of The Ketogenic Diet. “On a normal diet, the brain gets 100 percent of its energy from glucose. On a ketogenic diet, up to two-thirds of the brain’s energy comes from ketones. It’s understandable that brain function would change drastically on a ketogenic diet.” Here are 13 things doctors want you to know about the keto diet.

The keto lifestyle sounds daunting, but it really is not. One thing many fail to mention is the hormonal shifts that occur that regulate your appetite. Give this a little time, and you will be astounded at how easy it becomes to pass on the stuff you found addictive previously. There are many factors that influence one’s success or failure, and the key is to get the information and support you need, and to stick with it long enough to see the benefits. I fine this way of eating completely sustainable, and I’m in for life.


Even if you don't have a history with eating disorders, keto can still leave some people (although certainly not everyone!) with negative feelings around food. "For the vast majority of people, keto is not sustainable, meaning they don't stick with it for more than a few months," Brown says. "Not 'succeeding' with this diet and returning to one's usual eating habits can trigger feelings of guilt and failure." Those two feelings can actually trigger disordered eating in some people in the worst-case scenario, says Brown. (Also, We Seriously Need to Stop Thinking of Foods As "Good" and "Bad")
Avocados are the poster child of “good fats.” This type of fat, often found in plant-based foods, can be separated into polyunsaturated fats (found in fish and walnuts) and monounsaturated fats (found in avocados, flaxseed oils, nuts and seeds). There’s evidence that replacing saturated fats with “good” unsaturated fats can lower the risk of heart disease and help prevent insulin resistance.4
I must note here, that as a nutrition professional who has worked in pediatrics and seen children who must follow this diet, it is incredibly challenging for both the child and family. Most people who must follow this diet for therapeutic medical reasons have trouble actually reaching ketosis with diet alone, and need to drink poor-tasting formula drinks to keep their carb-to-fat ratio in tight control. Many of these individuals must follow this way of eating to survive or have any sort of quality of life.
I have great respect for Harvard Medical School. I notice that they support their readers posting comments and I am most appreciative of the article and all the many thoughtful comments by the readers. The readers seem to have the most expertise here and I hope that the doctor who wrote the article will think long and hard about the comments by readers. After 35 years of clinical practice in mental health, I notice that all issues of emotion involve medical issues, nutrition, and the gut bacteria. I would say that these issues and all of the executive brain functions seem to improve with ketogenic principles. For those that apply it in a flexible and smart manner, it appears to improve every area of their lives. I strongly encourage the author of the article to take one class via The Institute for Functional Medicine. If he is open to more learning he can take more classes and get certified. I’m sure a fine doctor, he will be an even better doctor and personally healthier, if he gets more training. Are we all open to new learning(especially us healthcare providers)?

The truth is though, her reaction is part of the problem. “I can’t believe your numbers improved so drastically without taking the medication.” THAT is the main problem with our medical community. They have been taught, and most have bought into the lie, that everything is better with medication. Medication is the go to. That is why we have so many health issues in this country. Let’s eat a crappy diet because our government/medical community recommends it…and then when that diet leads to medical complications…let’s throw drugs/medication at it. Many, if not the majority, of the medical issues we have could be done away with if we actually ate as we should. But no…we want cake.


Thank you for your objective review of the Keto Diet. I am not overweight but decided to try the Keto lifestyle because I have a lot of inflammation issues, including asthma and osteoarthritis. I had also been experiencing uncomfortable intestinal issues. I have been following the Keto lifestyle for 4 1/2 weeks, and I feel so much better- especially my stomach! I am eating a ton of leafy greens, broccoli and cauliflower. I am also enjoying Brussel sprouts, whole avacados and zucchini. I think the reason this is working well for me is because my body chemistry loves all the vegetables, good fats and protein. I also think that taking away sugar has had a big impact on how I feel. I’m just not eating grains and sugar. lots more veggies, berries, and consciously incorporating healthy fat. My stomach is flat again, and I have no more bloating or constipation. I have only lost 5 pounds, but I think my system is clean and operating better than it has in years. My point is that every person’s body chemistry is different. The Keto lifestyle seems to be what My body needed to feel my best. I did experience “the Keto flu” about a week into it, but it was short lived. I think that to be successful it is really important to eat a wide variety of veggies and good fats every day.

The keto diet is notorious for delivering a quick initial slim down. That’s because carbs hold on to more water than protein or fat, says Becky Kerkenbush, RD, a clinical dietitian at Watertown Regional Medical Center. So when you stop eating them, all that extra H2O gets released through urination. As a result, the scale might read a few pounds lower, and you may look a bit leaner.
Common complications of diabetic ketoacidosis include very low blood sugar, or hypoglycemia, and swelling of the brain (cerebral edema). As such, when a person is in ketoacidosis, there is such a high level of ketones produced that can push a person into cardiac arrest (heart attack) or kidney failure. Hence, the very important reason for taking occasional keto breaks go give your body a bit more nourishing carbs. 
"The keto diet is primarily used to help reduce the frequency of epileptic seizures in children. While it also has been tried for weight loss, only short-term results have been studied, and the results have been mixed. We don't know if it works in the long term, nor whether it's safe," warns registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women's Hospital.
But what I think is funny is that the keto diet has been staring us in the face forever. Look at Inuit tribes that survived off of blubber in a region that grows next to nothing most of the year. Yet their people didn’t die out or show signs of metabolic disorders or heart disease until introduced to the modern western diet that prioritizes carbohydrates over fat. Here is an interesting link, however I find the conclusion disheartening and frankly more than a little suspicious. (Basically the people in charge decided to drop the study and introduced a bunch of “what about…” questions to obfuscate a clear pattern in observation across many indigenous people from across the face of the planet and decided the outcome “wasn’t enough” to introduce into public policy…)
A ketogenic diet puts the body in a state of ketosis, where the primary fuel for the body is a broken down product of fat called ketone bodies. Ketosis can occur through reduction of carbohydrates in the diet or through fasting (or through taking an external ketone-producing product). It is the liver that produces ketone bodies by breaking down fatty acids, either from body fat or the fat that we eat.

Slightly increase carbs. If you wait a few more weeks and still have trouble with the ketone smell, you might consider eating slightly more carbs to reduce the ketosis. Try increasing to between 50 and 70 grams per day. You might also try combining this with intermittent fasting, such as only eating within an 8-hour window, to maintain the benefits of ketosis without the side effect of fruity breath.


A recent pilot study put five patients on the ketogenic diet (less than 20 grams per day of carbohydrate). At the end of six months, the average weight loss was 28 pounds (but this wasn’t the most surprising finding). Each patient underwent a liver biopsy, and four of the five patients had a reduction in liver fat, inflammation, and fibrosis. However, this is a small pilot study that also used supplements, so the results are not conclusive. What does the rest of the research say?

Of the many benefits of a keto diet, weight loss is often considered No. 1., as it can often be substantial and happen quickly (especially for those who start out very overweight or obese). The 2013 study published in the British Journal of Nutrition found that those following a keto diet “achieved better long-term body weight and cardiovascular risk factor management when compared with individuals assigned to a conventional low-fat diet (i.e. a restricted-energy diet with less than 30 percent of energy from fat).” (2)
Once you’ve stayed on keto for a couple of days, you may notice a new odor coming from your mouth that smells like overripe fruit or nail polish remover. This is an unfortunate side effect of ketosis that occurs when acetone (i.e., the primary ingredient in nail polish remover) is created as a by-product of ketone production. Unfortunately, your body can’t do much with the acetone it makes, so most of it will be excreted with each breath.
“These diets are so unsustainable and in the long term, just not worth it!” Most definitely in your opinion. I did a LOT of research on Keto before I started it in 2009. I lost 130lbs. It’s not a diet, it’s changing the way you think about food and fuel for your body. And once you do that you understand food freedom. I eat mostly Keto but if I want a beer and a piece of Watermelon I will let myself have one. True it’s not for everyone, not everyone has the willpower to control what they put in their mouth. We tend to reward ourselves with food instead of using it what its for, nourishment and fuel. It’s why our country is dying of obesity. Awesome that a size 10 women can put what she wants in her mouth everyday, exercise, and it not affect her weight but guess what, you are becoming the minority.
A great long-term benefit of the ketogenic diet is reduced cravings for sugar and other unhealthy foods. However, you might initially have stronger cravings for carbs during the transition period. This can last anywhere from one to two days to around three weeks. But stick it out! At the end, you’ll be pleased with the reduced, and often eliminated, cravings.

Cancer cells express an abnormal metabolism characterized by increased glucose consumption owing to genetic mutations and mitochondrial dysfunction. Previous studies indicate that unlike healthy tissues, cancer cells are unable to effectively use ketone bodies for energy. Furthermore, ketones inhibit the proliferation and viability of cultured tumor cells.
Eating a keto diet can have some short-term health perks. But in the long run, it also has the potential to create some serious health problems. That’s why many experts say you shouldn’t attempt it on your own. “In general, if a person follows a ketogenic diet, they should only do so for a brief time and under close medical supervision,” says Hultin.
Thanks for this article. I just started a Keto diet so found it appropriate to my current lifestyle. Though I don’t believe your bottom line is strong enough since you simply stating that the diet is “hard to follow” and food is “notoriously unhealthy” without evidence going deeper into why those “notoriously unhealthy” foods are worse than keeping carbohydrate-heavy food that are addictive and give the body a quick sugar high for energy. I believe “hard to follow” is your opinion only, since acceptable Keto foods are found at all restaurants easily and also all grocery stores. All the foods you mention: “rich in very colorful fruits and vegetables, lean meats, fish, whole grains, nuts, seeds, olive oil, and lots of water” are all Keto-friendly. Many people have been on a Keto-diet for years. A healthy lifestyle is a healthy mindset change and making right choices – it’s not going to be easy.
I’ve said many times before that keto dieters tend to eat less produce, either because they don’t like it and see keto as a free pass for near-carnivory, they worry about the carbs in produce throwing them out of ketosis, or they somehow think plants are restricted on keto. These are mistakes. Common ones. You can eat plenty of produce on keto. You should eat plenty of produce on keto. Mushrooms of all kinds. Leafy greens. Cruciferous veggies like broccoli, cauliflower, bok choy. Low-carb fruits like berries. Anything fibrous.
Now, there’s even evidence that a low-carb, high-fat regimen (as the keto diet is) helps you live longer, compared to a low-fat diet. In a study by the medical journal The Lancet that studied more than 135,000 adults from 18 countries, high carbohydrate intake was associated with higher risk of total mortality, whereas total fat and individual types of fat were related to lower total mortality. Total fat and types of fat were not associated with cardiovascular disease, myocardial infarction or cardiovascular disease mortality.
You sound weak I have given up all carbohydrates and fast acting insulin and had no issue with it ( real food is so delicious and satisfying)… and I don’t miss bread pasta and sugar at all… your mind is poisoned. It also has an added side effect , I now have no fat on my body. You uneducated money grubbing doctors and the sugar industry are the real problem here. My endocrinologist didn’t even bother to tell me about nutritional ketosis at all. I eat 80 to 85% good saturated fats out the 4000 calories I consume each day… not that difficult getting rid of crap sugar and carbs… these “doctors “ are lying to us and no one cares! It’s really disgusting …. I have no problem living without sugar…. and no studies done at all.. what the hell are these doctors doing, it seems pretty obvious to me$$$$.
In fact, the diet first gained popularity in the 1920s when it was discovered to have benefits for children suffering from extreme epilepsy. Now, researchers are conducting studies to determine whether it could have benefits for any number of disorders, including the treatment of ALS, Alzheimer’s disease, brain tumors, traumatic brain injury, diabetes, weight loss, polycystic ovary syndrome, glaucoma, Parkinson’s disease, narcolepsy, and some cancers.
Here’s the thing, the Keto diet can be executed in many different ways.  The only requirement for achieving ketosis is to restrict carbs and limit protein so that the bodies glycogen reserves are depleted to the point that ketosis kicks in.  If you do that by eating hot dogs and margarine then I agree with this claim, you are on a dangerous nutrient-deficient diet.  However, if one chooses to achieve ketosis by eating fatty cuts of quality meat, dairy, nuts and plenty green leaves and fibrous vegetables-they are on a nutrient dense, complete diet.
The low-carb diet induces ''nutritional ketosis," Dr. Saslow tells EndocrineWeb, which is not the same as ketoacidosis. Ketones are a chemical your body produces when you burn stored fat; if you are on a low-carb diet you may be ''in ketosis.'' Ketoacidosis is different; it is a life-threatening condition in which levels of ketones and blood sugar are dangerously high, which may occur in people who have poorly controlled diabetes.
Of the 28 participants enrolled in the study, 21 completed the 16 weeks of follow-up. Reasons for discontinuing the study included unable to adhere to study meetings and unable to adhere to the diet; no participant reported discontinuing as a result of adverse effects associated with the intervention. All but one of the 21 participants were men; 62% (n = 13) were Caucasian, 38% (n = 8) were African-American (Table ​(Table1).1). The mean age was 56.0 ± 7.9 years.
The keto diet also appears to help induce autophagy, which helps clear damaged cells from the body, including senescent cells that serve no functional purpose but still linger inside tissues and organs. In animal studies when rats are put on the ketogenic diet, autophagic pathways are created that reduce brain injury during and after seizures. (21)
According to Dr. Cabeca, “Fasting is a key aspect of a healthy diet and has many anti-aging effects.” In particular Dr. Cabeca recommends fasting to women during or after menopause due to it’s anti-aging effects. For example, a 2016 study published in the Journal of the American Medical Association found that when women went 12.5 hours between dinner and breakfast (a common form of fasting), the overnight fast seemed to help improve immune system functioning to the point that it reduced their risk for breast cancer. (03) 
Certain Cancers Keto may be used in combination with chemotherapy and radiation, some studies have suggested, including one published in November 2018 in the journal Oncology. (12) But ultimately more studies are needed to determine if keto can play a role in cancer therapy, and patients should not use it as a stand-alone treatment or without a doctor’s consent.
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