Ketogenic diets and their rapid weight loss effects
Virtually all weight loss diets, to varying degrees, focus on reducing calories or manipulating the intake of one of the three essential macronutrients (protein, fat, or carbohydrate) to achieve their weight loss effects.
Ketogenic diets are a group of “high fat, moderate protein” or “high protein, moderate fat” but very low carbohydrate diets. The term ketogenic basically refers to the increased production of ketone bodies caused by the high rate of lipolysis (breakdown of fat). Ketones are the acidic byproducts that are formed during the intermediate breakdown of “fat” into “fatty acids” by the liver.
The first sets of ketogenic diets were developed in the early 1920s by the Johns Hopkins Pediatric Epilepsy Center and also by Dr. RM Wilder of the Mayo Clinic to treat children with difficult-to-control seizures. The diets were designed to mimic the biochemical changes that occurred during periods of fasting, namely ketosis, acidosis, and dehydration. The diets involved the consumption of about 10-15 grams of carbohydrates per day, 1 gram of protein per kilogram of the patient’s body weight, and the rest of the calories derived from fat.
Today, advocates of ketogenic diets strongly believe that carbohydrates, especially high-glycemic ones, are the main reasons why people gain weight. Carbohydrate foods are generally metabolized to produce glucose, a form of simple sugar that is generally considered the preferred energy source for the body, since it burns the fastest energy. Although the body can break down muscle glycogen (a mixture of glucose and water) and fat for energy, it prefers to get it from high-glycemic carbohydrates in the diet.
Of the macronutrients, it is argued that carbohydrates are the main cause of weight gain. This is more because increased intake of high-glycemic carbohydrate foods usually causes fluctuating blood sugar levels due to their rapid absorption into the bloodstream and which, in most cases, leads to overproduction of insulin. This is where the problem really starts.
Insulin is a hormone that regulates blood glucose levels and thus the maintenance of the body’s energy input/output equation that governs body weight. Excessive amounts of glucose in the bloodstream cause excessive insulin secretion, which leads to storage of excess glucose in the body, either as glycogen in liver and muscle cells or as fat in fat cells.
Therefore, one of the goals of ketogenic diets is to reduce insulin production to a minimum, drastically reducing carbohydrate consumption while using fat and protein to supplement the body’s energy needs.
Despite the ability of ketogenic diets to reduce insulin production, their main goal is ultimately to induce a state of ketosis. Ketosis can be thought of as a condition or state in which the rate of formation of ketones produced by the breakdown of “fat” into “fatty acids” by the liver is greater than the ability of the tissues to oxidize them. Ketosis is actually a secondary state of the lipolysis (fat breakdown) process and is a general side effect of low-carb diets. Therefore, ketogenic diets are favorably arranged to encourage and promote ketosis.
Prolonged periods of starvation can easily induce ketosis, but it can also be deliberately induced using a low-calorie or low-carb diet by eating large amounts of fat or protein and drastically reducing carbohydrates. Therefore, diets high in fat and protein are the weight loss diets that are used to deliberately induce ketosis.
Essentially, ketosis is a very efficient form of energy production that does not involve the production of insulin, as the body burns its fat stores for energy. Consequently, the idea of cutting back on carbs not only reduces insulin production, but virtually forces the body to burn its fat stores for energy, making ketogenic dieting a very powerful way to achieve rapid weight loss.
Ketogenic diets are designed in such a way that they initially force the body to deplete its supply of glucose and then eventually switch to burning its fat stores for energy. Subsequent food intakes after inducing the ketosis state are intended to keep the ketosis process going by appropriately adjusting additional carbohydrate consumption to provide only the basic amount of calories needed by the body.
For example, the Atkins diet, which is obviously the most popular ketogenic diet, aims to help dieters achieve what the diet calls the individual’s Critical Carbohydrate Level for Maintenance (CCLM), a level of carbohydrate intake at which the dieter no longer gains or loses weight.
In 2003, the Johns Hopkins Treatment Center introduced a modified version of the Atkins diet protocol to treat a group of 20 children with epilepsy. After treatment, two-thirds were seen to experience a significant reduction in their seizures, while 9 were able to reduce their medication doses and none developed kidney stones.
In addition, there are ongoing scientific studies from the National Institutes of Health (NIH) on the efficacy of the classic ketogenic diet and modified versions of the Atkins diet in helping people lose weight and also in the treatment of epilepsy. It is equally interesting to note that the National Institute of Neurological Disorders and Stroke (NINDS) is conducting studies on the effect of ketogenic diets and also formulating drugs that may produce the same effect on weight reduction.