Those issues can be part of what's known as the “keto flu,” Warren says. Other side effects of the keto diet, all of which are tied to carb withdrawal, can include lightheadedness, nausea, mental fog, cramps, and headaches, in addition to tiredness. Luckily, the keto flu doesn't usually last more than a week—which is coincidentally about when people start to see the number on the scale go down, says Warren.
Advocates for the diet recommend that it be seriously considered after two medications have failed, as the chance of other drugs succeeding is only 10%. The diet can be considered earlier for some epilepsy and genetic syndromes where it has shown particular usefulness. These include Dravet syndrome, infantile spasms, myoclonic-astatic epilepsy and tuberous sclerosis complex.
Because some cancer cells are inefficient in processing ketone bodies for energy, the ketogenic diet has also been suggested as a treatment for cancer. A 2018 review looked at the evidence from preclinical and clinical studies of ketogenic diets in cancer therapy. The clinical studies in humans are typically very small, with some providing weak evidence for anti-tumour effect, particularly for glioblastoma, but in other cancers and studies, no anti-tumour effect was seen. Taken together, results from preclinical studies, albeit sometimes contradictory, tend to support an anti-tumor effect rather than a pro-tumor effect of the KD for most solid cancers.
It is not necessary to be as strict with children as you would be for yourself. Children are generally more insulin sensitive than adults, which means their bodies can deal with sugars and carbs more efficiently. Focus on whole foods, good sources of protein, lots of good fats (essential for brain development), and getting carbs from nutrient-dense sources.
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: