The diet suggests a specific number of servings of the recommended foods listed above. The sample plans provided by the National Heart Lung and Blood Institute (NHLBI) are based on 1600, 2000, or 2600 calories daily. For 2000 calories a day, this translates to about 6-8 servings of grains or grain products (whole grains recommended), 4-5 servings vegetables, 4-5 fruits, 2-3 low fat dairy foods, 2 or fewer 3-ounce servings of meat, poultry, or fish, 2-3 servings of fats and oils, and 4-5 servings of nuts, seeds, or dry beans per week. It advises limiting sweets and added sugars to 5 servings or less per week. The plan defines the serving sizes of each these food groups.
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. There is some evidence of synergistic benefits 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.
At the end of this 12 week study, scientists observed similar loss in body fat and overall body weight in all three diets. However, they noted that the VLCARB ketogenic diet was “more effective in improving tracylglycerols, HDL cholesterol, fasting and post-meal glucose and insulin concentrations. More specifically, triacylglycerols decreased by 39.9% in VLCARB subjects, 4.0% in VLF subjects, and 9.6% in HUF subjects. 
What the diet advocate says: Controversial Canadian psychologist Jordan Peterson is a fan, crediting the diet for curing his daughter’s various ailments, from juvenile arthritis to depression. But it was popularised by Shawn Baker, author of the aptly titled ‘The Carnivore Diet’ – in which he describes the diet as ‘a revolutionary, paradigm-breaking nutritional strategy that takes contemporary dietary theory and dumps it on its head’.
It is possible to combine the results of several small studies to produce evidence that is stronger than that available from each study alone—a statistical method known as meta-analysis. One of four such analyses, conducted in 2006, looked at 19 studies on a total of 1,084 patients. It concluded that a third achieved an excellent reduction in seizure frequency and half the patients achieved a good reduction.
The idea is that the fasting induces mild stress to the cells in your body, helping them become better at coping with such stress and possibly helping your body grow stronger. The verdict is still out regarding the diet’s long-term effectiveness with weight loss, according to a review of preliminary animal research published in January 2017 in Behavioral Sciences. (17)
First reported in 2003, the idea of using a form of the Atkins diet to treat epilepsy came about after parents and patients discovered that the induction phase of the Atkins diet controlled seizures. The ketogenic diet team at Johns Hopkins Hospital modified the Atkins diet by removing the aim of achieving weight loss, extending the induction phase indefinitely, and specifically encouraging fat consumption. Compared with the ketogenic diet, the modified Atkins diet (MAD) places no limit on calories or protein, and the lower overall ketogenic ratio (approximately 1:1) does not need to be consistently maintained by all meals of the day. The MAD does not begin with a fast or with a stay in hospital and requires less dietitian support than the ketogenic diet. Carbohydrates are initially limited to 10 g per day in children or 20 g per day in adults, and are increased to 20–30 g per day after a month or so, depending on the effect on seizure control or tolerance of the restrictions. Like the ketogenic diet, the MAD requires vitamin and mineral supplements and children are carefully and periodically monitored at outpatient clinics.
WH Verdict: Not all lectins are created equal and research into their impact on the body is ongoing. In fact, to date, there are no human studies linking the dietary lectins with a harmful immune response in healthy people. A lectin-free diet is also incredibly restrictive, with the list of foods you can’t eat reading like a typical shopping list for your average nutrition-conscious foodie, making it unsustainable and putting you at risk of nutritional deficiencies.
Many diets, including Atkins and the keto diet, fit into this umbrella. A typical low-carb diet limits carbs to less than 60 g daily, but this can vary, according to the Mayo Clinic. (15) In a September 2015 review published in PLoS One, people following low-carb diets saw modest weight loss — although study authors note that long-term effects of the diet require further research. (16)
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.
When you’re eating the foods that get you there (more on that in a minute), your body can enter a state of ketosis in one to three days, she adds. During the diet, the majority of calories you consume come from fat, with a little protein and very little carbohydrates. Ketosis also happens if you eat a very low-calorie diet — think doctor-supervised, only when medically recommended diets of 600 to 800 total calories.