There’s no scientific definition of keto flu, but it’s often described as flu-like symptoms that start soon after a person cuts carbohydrates largely out of their diet. (To enable “ketosis,” a sort of starvation mode in which the body burns fat rather than glucose, the ketogenic diet allows for only 2% to 5% of a person’s daily calories to come from carbohydrates.)
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.
Children who discontinue the diet after achieving seizure freedom have about a 20% risk of seizures returning. The length of time until recurrence is highly variable, but averages two years. This risk of recurrence compares with 10% for resective surgery (where part of the brain is removed) and 30–50% for anticonvulsant therapy. Of those who have a recurrence, just over half can regain freedom from seizures either with anticonvulsants or by returning to the ketogenic diet. Recurrence is more likely if, despite seizure freedom, an electroencephalogram shows epileptiform spikes, which indicate epileptic activity in the brain but are below the level that will cause a seizure. Recurrence is also likely if an MRI scan shows focal abnormalities (for example, as in children with tuberous sclerosis). Such children may remain on the diet longer than average, and children with tuberous sclerosis who achieve seizure freedom could remain on the ketogenic diet indefinitely.
In addition to keeping you adequately hydrated -- which can also help alleviate constipation -- drinking lots of water can also help offset still another low-carb diet problem: bad breath. The ketones produced during the diet can lead to what is sometimes described as a fruity odor although it is often described as having an almost "chemical" odor similar to acetone or nail polish remover.
The ketogenic diet is indicated as an adjunctive (additional) treatment in children and young people with drug-resistant epilepsy. It is approved by national clinical guidelines in Scotland, England, and Wales and reimbursed by nearly all US insurance companies. Children with a focal lesion (a single point of brain abnormality causing the epilepsy) who would make suitable candidates for surgery are more likely to become seizure-free with surgery than with the ketogenic diet. About a third of epilepsy centres that offer the ketogenic diet also offer a dietary therapy to adults. Some clinicians consider the two less restrictive dietary variants—the low glycaemic index treatment and the modified Atkins diet—to be more appropriate for adolescents and adults. A liquid form of the ketogenic diet is particularly easy to prepare for, and well tolerated by, infants on formula and children who are tube-fed.
Sleep enough and minimize stress. Most people benefit from a minimum of seven hours of sleep per night on average. And try to keep stress under control. Sleep deprivation and stress hormones raise blood sugar levels, slowing ketosis and weight loss. Plus they might make it harder to stick to a keto diet and resist temptations. So while handling sleep and stress will not get you into ketosis on their own, they are still worth thinking about.