The VLCK diet was used because of its ability to produce a rapid and well-tolerated weight loss with a ketogenic phase that lasts 60-90 days and a final result of 20 kg of weight reduction at 4 months. The rapid reduction in weight is the probable explanation of the positive effects of this dieting approach, which are evident 1 and 2 years later (12, 13). Four different stages occurred with the VLCK diet used: a basal stage with obese body weight and no ketosis, a second stage with extreme ketosis and marked body weight loss, a third stage with body weight loss and declining ketosis, and a fourth stage with weight loss and no ketosis. Body composition was studied with the 3 techniques at each of these stages.
When following a low carbohydrate diet, for the first few days, there is an adaptation period during which most people report feeling run-down or tired. Some people report feeling irritable, out of sorts, and unable to make decisions. For most people, these feelings disappear after the adaptation period, however, and are replaced with feelings of calm and balance and more consistent energy.[1]
A systematic review of 26 short-term intervention trials (varying from 4-12 weeks) evaluated the appetites of overweight and obese individuals on either a very low calorie (~800 calories daily) or ketogenic diet (no calorie restriction but ≤50 gm carbohydrate daily) using a standardized and validated appetite scale. None of the studies compared the two diets with each other; rather, the participants’ appetites were compared at baseline before starting the diet and at the end. Despite losing a significant amount of weight on both diets, participants reported less hunger and a reduced desire to eat compared with baseline measures. The authors noted the lack of increased hunger despite extreme restrictions of both diets, which they theorized were due to changes in appetite hormones such as ghrelin and leptin, ketone bodies, and increased fat and protein intakes. The authors suggested further studies exploring a threshold of ketone levels needed to suppress appetite; in other words, can a higher amount of carbohydrate be eaten with a milder level of ketosis that might still produce a satiating effect? This could allow inclusion of healthful higher carbohydrate foods like whole grains, legumes, and fruit. [9]
The ADA say low-carbohydrate diets can be useful to help people with type 2 diabetes lose weight, but that these diets were poorly defined, difficult to sustain, unsuitable for certain groups of people and that, for diet composition in general, "no single approach has been proven to be consistently superior".[13] Overall, the ADA recommend people with diabetes should be "developing healthy eating patterns rather than focusing on individual macronutrients, micronutrients, or single foods". They recommended that the carbohydrate in a diet should come from "vegetables, legumes, fruits, dairy (milk and yogurt), and whole grains"; highly-refined foods and sugary drinks should be avoided.[13]
I prescribe nutritional ketosis for my patients with brain and focus issues, such as: epilepsy, attention deficit, brain fog, traumatic brain injury, memory issues, mild cognitive impairment, Parkinson’s disease, and Alzheimer’s disease (including patients with one or two copies of the genes for Alzheimer’s, called ApoE4). Most of my patients on keto say they feel smarter, sharper, and more focused—and some may lose weight (fat) as a result of using ketones as fuel.
In steps 4 or 5, the ketogenic phases were ended by the physician in charge of the patient based on the amount of weight lost, and the patient started a low-calorie diet (800–1500 kcal/day). At this point, the patients underwent a progressive incorporation of different food groups and participated in a program of alimentary re-education to guarantee the long-term maintenance of the weight loss. The maintenance diet consisted of an eating plan balanced in carbohydrates, protein, and fat. Depending on the individual, the calories consumed ranged between 1500 and 2000 kcal/day, and the target was to maintain the weight lost and promote a healthy lifestyle.