Our human ancestors did not consume high-fat, low-carbohydrate diets and therefore would not have been in diet-induced ketosis. Even the most successful early hunters could not possibly have consumed enough fat to enter ketosis since african wildlife such as wildebeests, warthogs and impalas all have low body fat – well under 10%, and as low as 0.3%[6] in the dry season.
Meanwhile, more than 70 trials have examined the health effects of a low-carb diet. They attest to the benefits64 associated with ketosis and low-carb diets, including a reduction in body weight and body mass index, improved cardiovascular risk factors including blood pressure, and the reversal of Type 2 diabetes. It is virtually impossible to imagine that a diet with so many health improvements in the ‘near term’ (2 years) could ultimately shorten life—and the study authors offer no possible mechanism to explain how this might happen.
First, that study, which was reported upon widely, was on mice. Mice are not like humans in the way they fatten or contract metabolic diseases. Journalists/media should stop reporting on mice stories as if they were applicable to humans, especially when there is such a large body of clinical trial data on humans. Let’s be clear: rigorous clinical trial data on humans trumps any data on mice. Every time. And what does the rigorous data on humans say?

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]
For patients who benefit, half achieve a seizure reduction within five days (if the diet starts with an initial fast of one to two days), three-quarters achieve a reduction within two weeks, and 90% achieve a reduction within 23 days. If the diet does not begin with a fast, the time for half of the patients to achieve an improvement is longer (two weeks), but the long-term seizure reduction rates are unaffected.[44] Parents are encouraged to persist with the diet for at least three months before any final consideration is made regarding efficacy.[9]
This is one area where full keto and Bulletproof differ. Except for coconut, all nuts and legumes are suspect on the Bulletproof Diet and should be limited. All expose you to high amounts of omega-6s, inflammatory oxidized fats, mold toxins, and phytates (plant anti-nutrients). Peanuts are one of the main sources of mold toxins in our diets, and often trigger allergic responses with inflammatory polyunsaturated fats, lectins and histamines. The Bulletproof Diet also excludes all soy products due to their phytoestrogen content, which messes with your hormones and may promote cancer.
The low glycaemic index treatment (LGIT)[49] is an attempt to achieve the stable blood glucose levels seen in children on the classic ketogenic diet while using a much less restrictive regimen. The hypothesis is that stable blood glucose may be one of the mechanisms of action involved in the ketogenic diet,[9] which occurs because the absorption of the limited carbohydrates is slowed by the high fat content.[5] Although it is also a high-fat diet (with approximately 60% calories from fat),[5] the LGIT allows more carbohydrate than either the classic ketogenic diet or the modified Atkins diet, approximately 40–60 g per day.[18] However, the types of carbohydrates consumed are restricted to those that have a glycaemic index lower than 50. Like the modified Atkins diet, the LGIT is initiated and maintained at outpatient clinics and does not require precise weighing of food or intensive dietitian support. Both are offered at most centres that run ketogenic diet programmes, and in some centres they are often the primary dietary therapy for adolescents.[9]
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.”
Type 2 diabetes. One study found that being on the keto diet for one year reversed diabetes for up to 60 percent of participants. With an average weight loss of 30 pounds, they dramatically reduced or eliminated their need for insulin and no longer needed oral hypoglycemic drugs. The keto diet is also easier to sustain than the calorie-restricted diet or the protein-sparing modified fast.
Low carb diets focus on keto recipes (also known as ketogenic recipes) like the ones below to keep your blood sugar stable, helping your body regain insulin sensitivity and keeping your mood and energy levels stable. Also, since processed food has so many additives – usually sugar included – low carb diets encourage you to cook for yourself. This leads to eating more whole foods and improving your diet in that way as well.
Early studies reported high success rates; in one study in 1925, 60% of patients became seizure-free, and another 35% of patients had a 50% reduction in seizure frequency. These studies generally examined a cohort of patients recently treated by the physician (a retrospective study) and selected patients who had successfully maintained the dietary restrictions. However, these studies are difficult to compare to modern trials. One reason is that these older trials suffered from selection bias, as they excluded patients who were unable to start or maintain the diet and thereby selected from patients who would generate better results. In an attempt to control for this bias, modern study design prefers a prospective cohort (the patients in the study are chosen before therapy begins) in which the results are presented for all patients regardless of whether they started or completed the treatment (known as intent-to-treat analysis).[19]
People claiming huge benefits of these supplements – despite the lack of solid scientific support – may sometimes have a financial reason to believe in the supplements. Some of these products are sold under a multi-level marketing arrangement, where sales people are paid based on commission. For example, the company Prüvit sells drinkable ketones, called KETO//OS with a multi-level marketing structure.