These affect your brain and spine, as well as the nerves that link them together. Epilepsy is one, but others may be helped by a ketogenic diet as well, including Alzheimer’s disease, Parkinson’s disease, and sleep disorders. Scientists aren’t sure why, but it may be that the ketones your body makes when it breaks down fat for energy help protect your brain cells from damage.
In Asia, the normal diet includes rice and noodles as the main energy source, making their elimination difficult. Therefore, the MCT-oil form of the diet, which allows more carbohydrate, has proved useful. In India, religious beliefs commonly affect the diet: some patients are vegetarians, will not eat root vegetables or avoid beef. The Indian ketogenic diet is started without a fast due to cultural opposition towards fasting in children. The low-fat, high-carbohydrate nature of the normal Indian and Asian diet means that their ketogenic diets typically have a lower ketogenic ratio (1:1) than in America and Europe. However, they appear to be just as effective.[54]
A survey of 1,580 low-carb consumers published in late 2017 by the Journal of Insulin Resistance45 found that while more than 11% of respondents reported using sleep-aids before beginning their low-carb diet, less than 5% reported using them after their diet. Moreover, nearly seven in 10 reported improved quality of sleep after dieting while only 3.4% said their sleep quality had worsened.
Around this time, Bernarr Macfadden, an American exponent of physical culture, popularised the use of fasting to restore health. His disciple, the osteopathic physician Dr. Hugh William Conklin of Battle Creek, Michigan, began to treat his epilepsy patients by recommending fasting. Conklin conjectured that epileptic seizures were caused when a toxin, secreted from the Peyer's patches in the intestines, was discharged into the bloodstream. He recommended a fast lasting 18 to 25 days to allow this toxin to dissipate. Conklin probably treated hundreds of epilepsy patients with his "water diet" and boasted of a 90% cure rate in children, falling to 50% in adults. Later analysis of Conklin's case records showed 20% of his patients achieved freedom from seizures and 50% had some improvement.[10]
Because it lacks carbohydrates, a ketogenic diet is rich in proteins and fats. It typically includes plenty of meats, eggs, processed meats, sausages, cheeses, fish, nuts, butter, oils, seeds, and fibrous vegetables. Because it is so restrictive, it is really hard to follow over the long run. Carbohydrates normally account for at least 50% of the typical American diet. One of the main criticisms of this diet is that many people tend to eat too much protein and poor-quality fats from processed foods, with very few fruits and vegetables. Patients with kidney disease need to be cautious because this diet could worsen their condition. Additionally, some patients may feel a little tired in the beginning, while some may have bad breath, nausea, vomiting, constipation, and sleep problems.
For many people, one of the more surprising side effects of starting a ketogenic diet is a bout with the “keto flu.” How so? “When you go on this diet, your kidneys don’t retain as much salt or water, which can lead to flu-like symptoms, such as fatigue and headache, or constipation,” says Laura Saslow, PhD, an assistant professor at the University of Michigan School of Nursing. “But these are typically short-lived symptoms that can be prevented or treated by increasing your salt and water intake.” However, if you have high blood pressure, speak with your doctor before adding more sodium to your diet. And know that the keto flu only lasts a week or two; symptoms typically subside once the body adjusts to the diet.
Of the 1,580 survey participants, more than half reported staying on a low-carb diet for at least one year, and 34% reported more than two years. Further, those on the diet for two years or more said that they had largely maintained their weight loss. This is a self-selected sample, with an obvious bias for people who are experiencing success (dieters are less inclined to report on their failures). However, this data does show that long-term adherence is possible.
A survey in 2005 of 88 paediatric neurologists in the US found that 36% regularly prescribed the diet after three or more drugs had failed, 24% occasionally prescribed the diet as a last resort, 24% had only prescribed the diet in a few rare cases, and 16% had never prescribed the diet. Several possible explanations exist for this gap between evidence and clinical practice.[34] One major factor may be the lack of adequately trained dietitians, who are needed to administer a ketogenic diet programme.[31]

I was a Corpsman (not a corpse-man as some recent somewhat fanatical president would say), and I can tell you many stories of Marines and Sailors who maintained restrictive diets (aka picky eaters). Most obvious was lack of sustaining energy (hypoglycemia) at mile 15 (with 80lbs of gear including a 6.5lb rifle and 200 rnds of ammo, etc.) and depletion of essential vitamins, electrolyte imbalance. They were always the first to collapse and have to hear me scold “see I told you so.” An IV of D5W usually does the trick (D is for dextrose, OMG!)

In fact, patients with gastroesophageal reflux disease (GERD) have been shown to improve after eating very low carbohydrate diets.31, 32 Another study found increased carb-intake worsened GERD, while a high-fat, low-carbohydrate diet reduced symptoms.33 And two studies have linked esophageal diseases, including Barrett’s esophagus (BE)34 and GERD,35 to sugar and carbohydrate intake.


The ketogenic diet is usually initiated in combination with the patient's existing anticonvulsant regimen, though patients may be weaned off anticonvulsants if the diet is successful. Some evidence of synergistic benefits is seen when the diet is combined with the vagus nerve stimulator or with the drug zonisamide, and that the diet may be less successful in children receiving phenobarbital.[18]
Still, the headlines keep coming. Men’s Health declared, “Ketogenic Diet Side Effects: How the Trendy Low-Carb Diet Can Give You Acne.” The health and fitness website Livestrong.com warned about “The Ketogenic Diet and Insomnia.” Other articles raised fears of bloat and constipation or cautioned that the regimen requires inhuman willpower from its followers.
On the ketogenic diet, carbohydrates are restricted and so cannot provide for all the metabolic needs of the body. Instead, fatty acids are used as the major source of fuel. These are used through fatty-acid oxidation in the cell's mitochondria (the energy-producing parts of the cell). Humans can convert some amino acids into glucose by a process called gluconeogenesis, but cannot do this by using fatty acids.[57] Since amino acids are needed to make proteins, which are essential for growth and repair of body tissues, these cannot be used only to produce glucose. This could pose a problem for the brain, since it is normally fuelled solely by glucose, and most fatty acids do not cross the blood–brain barrier. However, the liver can use long-chain fatty acids to synthesise the three ketone bodies β-hydroxybutyrate, acetoacetate and acetone. These ketone bodies enter the brain and partially substitute for blood glucose as a source of energy.[56]
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The ketogenic diet is a mainstream dietary therapy that was developed to reproduce the success and remove the limitations of the non-mainstream use of fasting to treat epilepsy.[Note 2] Although popular in the 1920s and '30s, it was largely abandoned in favour of new anticonvulsant drugs.[1] Most individuals with epilepsy can successfully control their seizures with medication. However, 20–30% fail to achieve such control despite trying a number of different drugs.[9] For this group, and for children in particular, the diet has once again found a role in epilepsy management.[1][10]


Physicians of ancient Greece treated diseases, including epilepsy, by altering their patients' diet. An early treatise in the Hippocratic Corpus, On the Sacred Disease, covers the disease; it dates from c. 400 BC. Its author argued against the prevailing view that epilepsy was supernatural in origin and cure, and proposed that dietary therapy had a rational and physical basis.[Note 3] In the same collection, the author of Epidemics describes the case of a man whose epilepsy is cured as quickly as it had appeared, through complete abstinence of food and drink.[Note 4] The royal physician Erasistratus declared, "One inclining to epilepsy should be made to fast without mercy and be put on short rations."[Note 5] Galen believed an "attenuating diet"[Note 6] might afford a cure in mild cases and be helpful in others.[11]
The modified Atkins diet reduces seizure frequency by more than 50% in 43% of patients who try it and by more than 90% in 27% of patients.[18] Few adverse effects have been reported, though cholesterol is increased and the diet has not been studied long term.[48] Although based on a smaller data set (126 adults and children from 11 studies over five centres), these results from 2009 compare favourably with the traditional ketogenic diet.[18]

Still, the headlines keep coming. Men’s Health declared, “Ketogenic Diet Side Effects: How the Trendy Low-Carb Diet Can Give You Acne.” The health and fitness website Livestrong.com warned about “The Ketogenic Diet and Insomnia.” Other articles raised fears of bloat and constipation or cautioned that the regimen requires inhuman willpower from its followers.
Achieving ketosis is a pretty straightforward, but it can seem complicated and confusing with all of the information out there.4If you want to learn more about ketosis and the scientific process around it, you can visit a very in-depth discussion about on Dr. Peter Attia’s website. Here’s the bottom line on what you need to do, ordered in levels of importance:
People use a ketogenic diet most often to lose weight, but it can help manage certain medical conditions, like epilepsy, too. It also may help people with heart disease, certain brain diseases, and even acne, but there needs to be more research in those areas. Talk with your doctor first to find out if it’s safe for you to try a ketogenic diet, especially if you have type 1 diabetes.
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