The ketogenic diet is a high-fat, low-carb diet that has been trending of late. It promises to help folks lose weight, balance stubborn blood sugars, rip your abs, and help reset the body’s ability to use fats as a primary fuel supply. But is it safe?
With more than 1/3 of Americans being pre-diabetic and obese (1), shifting the body to burn fat instead of sugar and carbs for energy is an urgent need, but is the ketogenic diet the best way to do so? Let’s find out!
The ketogenic diet is different than a paleo diet. The paleo diet restricts refined and processed foods, grains, legumes and dairy, which naturally makes it a lower carb, higher protein and higher fat diet. Paleo doesn’t restrict starchy vegetables, like potatoes and tubers, while a ketogenic diet strictly restricts carbohydrates.
A classic ketogenic diet is composed of 80-90% fat, with carbohydrates and proteins constituting the remainder of the intake. The diet provides sufficient protein for growth, but insufficient amounts of carbohydrates for the body’s metabolic needs. Energy is largely derived from the utilization of body fat, and by fat delivered in the diet. These fats are converted to the ketone bodies β-hydroxybutyrate, acetoacetate, and acetone, which provide an alternative energy source to glucose or sugar. (5)
Fatty acids, in the form of ketones, are the main source of cellular energy production. Ketones can easily cross the blood-brain barrier, and can act as a powerful fuel supply for the brain and central nervous system. (5)
Shifting the body to burn fats or ketones can support the body in many ways. The ketogenic diet was first used in the 1920s for epilepsy, and is still used for that purpose today. (3) It has shown to be effective for certain cancers, as it starves the cancer cells of sugar. (4) Burning ketones from a high-fat, low-carb diet has shown to be neuro-protective for the brain, boost brain mitochondria cells, reduce inflammation, boost memory, and deliver more energy and antioxidants while protecting against Alzheimer’s and Parkinson’s. (5)
Ketogenic Diet Risks
Numerous studies have found a ketogenic diet to be successful in managing weight gain and obesity. (2) Other studies contradict the use of a ketogenic, high-fat diet for weight loss.
One study compared a low-carb, ketogenic diet with a low-carb, non-ketogenic diet. The weight loss was the same for both, but cited side effects from the low-carb ketogenic diet. (3)
Other studies have found that long-term use of a ketogenic diet can cause arterial stiffness. (6) Other side effects include dehydration, gastrointestinal disturbances, such as nausea, vomiting, diarrhea, constipation, gastritis and fat intolerance. (7) Long-term use may increase the risk of osteopenia, renal stones, cardiomyopathy, secondary hypocarnitinemia, and iron-deficiency anemia. (7)
While the ketogenic diet is generally regarded as safe, in isolated cases, the long-term complications can be life-threatening. (8,9,10,11)
The Ayurvedic Perspective
Whenever I come across conflicting scientific studies, I generally like to look to ancient wisdom to help break the tie. As a hunter-gatherer, it would be impossible to eat a ketogenic diet. Remember, it was devised as a medicinal diet for epilepsy, and not as a way-of-life diet. Think about it… How could traditional people eat a diet consisting of 80-90% fat? We only recently developed techniques to press oil out of seeds and nuts. An extreme diet such as keto would be nearly impossible for our ancestors!
The only culture that came close to eating a ketogenic diet were the Inuit people of the Arctic, who had a naturally-occurring, very high-fat, low-carb diet of mostly seal blubber and fish meat. Amazingly, they acquired a gene to block them from going into ketogenesis from their super high-fat diet. (12) The question begging to be asked here is, why would the only culture who naturally ate a ketogenic diet acquire a gene to prevent ketogenesis if the ketogenic diet was in fact a health-promoting diet?
The fact is that a ketogenic diet is a starvation diet. Yes, we have evolved to thrive in times of starvation and become ketogenic for short periods of time—like every late spring, when food stores would commonly run out and it would be too early for a harvest. However, this kind of ketogenesis was not from eating a diet of 70-80% fat. It was from fasting!
There are natural dietary shifts that take place each season: A high-protein, high-fat diet in the winter, a high-carbohydrate diet in the summer from lots of veggies, fruits and grains, and a very low-fat diet in the spring.
Traditionally, late winter into late spring represented a time of famine, when foods were scarce as a result of a long winter with no vegetation. More hunting was done, roots were dug up, but by all accounts, food in general was hard to come by. Surviving the winter and early spring was a feat in itself, followed by solstice celebrations to welcome back the sun and vegetation in late spring.
This is why fasting—a popular variation of a ketogenic diet—became a part of traditional cultures. Native Americans went on fasting vision quests, and fasting religious practices, like Lent and Ramadan, are still a part of cultures today. These rituals are from times past, when the early spring was a period of scarcity. Traditional life was a balance of feast and famine, with the feast being at the end of summer, and the famine being at the end of winter and early spring. Intermittent fasting was commonplace in ancient times, not only in the spring, but a day or two without food could come at any time, year-round.
Each spring, the body was forced to burn its own fat—the goal of a ketogenic diet—as a source of fuel, as there was minimal fat available in the diet. It was a natural time of calorie restriction that forced the body to reset its ability to use fat as a primary source of fuel. This form of ketosis and fat-burning was not caused by a low-carb, super high-fat, ketogenic diet, but it was, in fact, a very ketogenic time.
The beauty here is that nature only delivers such scarcity and ketogenesis for just a couple months of the year. This is intriguing, as most of the side effects and complications of a ketogenic diet were from long-term, not short-term use. (6-11)
Dr. John’s Take
According to Ayurveda and to what we experience in nature, a ketogenic diet (as currently recommended with 70-80% fat in the diet) is extreme. It may have only been practiced by Inuit’s in Arctic regions—and even they acquired a gene to block ketogenesis! That said, seasonal ketogenesis, as I described above, does happen naturally every spring, as we experience food scarcity and often famine at that time.
The modern ketogenic diet, as outlined today, was created as a medicinal diet, and I believe it is still as such. It is in my opinion that any medicinal diet that you get on, get better and then get off the diet.
The ketogenic diet can be a great way to reset fat-burning for 2-week, maybe 3-week stints. Once fat-burning has been re-established, I suggest going back to a seasonal diet. To maintain fat-burning as a significant source of fuel and mood, detox, energy and sleep stability, we must constantly be reminded of our cultural tendency to eat too much food. We should strive to lower the amount of food we eat, as well as our frequency of eating.
The spring should be a time to eat less of everything. In particular, less carbohydrates, as they are mostly not harvested until fall. We can all do this quite naturally by following my free seasonal eating guide, where we deliver seasonal grocery lists, superfood lists, and seasonal recipes to your inbox each month.
Stay tuned this spring, as I will guide you through a natural, fat-burning ketogenic reset.
Great video on the ketogenic diet . I’m looking forward to my video on this topic
Dear Dr. John,
Around the year 2000, I was suffering from IBS. It was pretty bad. Since then, I have made huge changes per your teachings. I don’t have IBS, anymore. I have no problems in the bathroom. My digestive fire has done a 180 degree turn from what it was in 2000. That said, I still believe that I have Thyroid/hormonal issues. I have continued to eat organic wheat and dairy. Recently, I took an IgG blood panel to look at any food sensitivities as I am hanging on to weight. The results showed that I am moderately sensitive to wheat and gluten (in the yellow zone) and highly sensitive (in the low red zone) to dairy and baker’s yeast. So, even though my digestive fire is strong, is it possible that I simply have attained a sensitivity to these foods from my years of bad eating? I do feel better when I stay off wheat and diary, however, I don’t believe it’s a good idea to take the body completely off such foods because it will only heighten the sensitivity. It’s also odd to me because I am of strong European decent, Scottish/Irish/English. They ate wheat and dairy. Maybe more detoxing from my years of eating bad would help? I don’t think the body decides to be sensitive to certain foods for no reason. Something caused/is causing it.
This may sound simple minded, but if you do indeed have thyroid issues, perhaps iodine supplementation can be helpful; it has worked for some people. Just saying. Good luck to you.
Our modern dairy is essentially highly processed and no longer a natural food. Wheat has been altered to have more gluten but is also sprayed with glyphosate just before harvesting. Glyphosate is highly toxic. If you desire to eat wheat then look for an organic ancient wheat. If you desire to eat dairy then look for raw organic. Good luck there! Our governments have made those almost impossible to find.
Tina,
I went through something similar! I did various things to get my liver/ stomach working so much better, and went back on organic sprouted gluten, for almost 9 months! It was a miracle as I had been almost celiac level responsive (but not celiac) for 4 years, and now I had No symptoms! The first few months I felt fine! The next few I was exhausted and had hip arthritis, but didn’t have any stomach pain from gluten, so I didn’t know why. The next few months my stomach symptoms returned, all while doing ayruvedic things to support stomach/ intestines/ liver. I went off gluten again and felt infinitely better! I’d look at gluten expert Dr Tom Obryan who gives the advice that we’re all so messed up with toxins and messed up hormones, now a days, that no human can fully break it down. He cites various studies showing 100% of people had tears in their GI lining from it. It causes tears and leaky gut and some just heal quicker than others. Some heal within 24 hours, but the ones who take any longer to heal are the ones with problems. It’s a different world we live in now a days and I think we’d be better if we kept the trend to 98-100% avoid it. Also, just because one isn’t having stomach issues, doesn’t mean gluten isn’t drastically affecting other parts of the body!! And sometimes you have no idea they are related.
Anyways, I loved this article and I agree! I’d love to hear more on water fasting!
I have begun probiotics and twice a week i drink water that has rested in a clean copper vessel overnight (8hrs) and my swelling on my neck has reduced first time in a year. wishing you wellness.
Most of persons whoa are suffering with diabetics following ketogenic diet to overcome from the disease. they happily lived with ketogenic diet without any complications of diabetics. moreover they said” they have get rid of diabetics, because of high fat low coarbs foods.
What is your openion to follow ketogenic diet for whom suffering with type 2 diabetics and cardio vascular disease patients?
Could you sugeest the right diet for Heart Patients withtpe 2 diabetics?
Thank you for the article on the ketogenic diet! I have read about all the health problems that it could solve, but I wondered if there were any side effects. Also, I’ve wondered if any groups of people around the world have thrived on this type of restrictive diet, another one being the vegan diet. The article had the answers.
I’m still curious about how following a ketogenic diet would affect me. Now I think I might try it in early spring and limit it to one or two months.
As an aside, I did the 23 and me genetic testing and found out I’m genetically predisposed to celiac problems and lactose intolerance. I’d figured this out myself several years ago myself, but it took many decades.
I have the book Eat Wheat and am using some of its suggestions to rev up my digestive system, so thank you for the wonderful book! I probably won’t be eating wheat, but my husband is using organic whole wheat to make his bread now, and I found a local source for buying organic sprouted whole wheat and organic sprouted Khorasan flour(Lucky’s market on High St. in Columbus, Ohio)
I have been attracted to the ketogenic approach by the literature that suggests it can help fight cancer by starving cancer cells. I have been observing a vegetarian version for the past 4 or 5 weeks, with a few variations here and there. About 7 years ago i had a cancerous polyp removed from my colon, and rejected all radiation and chemo. My function in that area has been quite regular since then, but I avoid colonoscopies because I have also been through two other major abdominal surgeries and know that my colon and intestines are likely not in their normal configurations due to connective tissue growth (one of the surgeries actually had to correct this when post surgical connective tissue growth entirely blocked a section of my small intestine). I feel that colonoscopies are more than usually hazardous for me, so I just monitor my stool. I also take a number of supplements to combat/prevent cancer and try to incorporate any advice I encounter that serves that purpose. The ketogenic diet so far seems to work very well for me, giving me sustained energy and stabilizing my weight at an acceptable level. I am not particularly trying to lose weight, but also do not want to gain. It sounds like you might recommend being more strictly keto sometimes (especially in late winter and spring) and less strict about it at other times (summer and fall perhaps). How would you recommend that I vary the diet to nevertheless keep on serving my interest in starving cancer cells?
I recently embarked on a ketogenic way of eating and I’ve found it very satisfying. There’s no doubt that many thousands of people have found it to be beneficial in re-balancing their health issues. Having said that, I’ve always felt that any eating regime that excluded natural foods just didn’t seem natural. Ketogenic diets are just that. I don’t miss sugar as such but I do miss fruit, one of nature’s most glorious bounties! It’s also quite expensive. As you pointed out in your article, “keto” was designed in response to a medical issue (or issues) and I guess that means that it really shold be though of as a kind of “medicine”. As I’ve said to my marajuana toking friends, why are you taking medicine if you’re not sick?
Along this line of thinking I have been thinking about seasonal cycles of eating, which you’ve explained so well in your article. Another aspect you touch upon is how regional diets have impacted generational adaptations – Innuits with high fat, some parts of Europe and Africa with lactose, etc. I’m from the Pacific where, for thousands of generations we’ve eaten no grains or legumes, just root vegetables, fruit, seafood, birds and pigs. To this end I’m keen to try a more natural cycle of eating as you have described where seasonal changes include both fasting and ketogenic type diets. I usually grow many of my own vegetables and buy produce from the local farmers market where items are only available “in season”.
It takes a great deal more energy to maintain homeostasis in the cold. It would not benefit an animal in such an environment to efficiently burn through their most reliable energy source which they would likely not be able to survive/thrive long-term without. Wouldn’t presume that genes optimised for storing fat or using them sparingly suggests fats or associated metabolites are unhealthy. Interesting question in any case.