The ketogenic (or “keto”) diet is a low-carbohydrate, high-fat eating regimen that has been used to treat various medical problems for millennia. The ketogenic diet was widely utilised to help manage diabetes in the nineteenth century. It was launched in 1920 as a successful therapy for epilepsy in children who had failed to respond to medicines. The ketogenic diet has also been used to treat cancer, diabetes, polycystic ovarian syndrome, and Alzheimer’s disease in carefully supervised conditions.
Due to the low-carb diet fad that began in the 1970s with the Atkins diet, this diet is receiving a lot of interest as a possible weight-loss approach (a very low-carbohydrate, high-protein diet, which was a commercial success and popularised low-carb diets to a new level). Other low-carb diets, including as the Paleo, South Beach, and Dukan, are rich in protein but low in fat today. The ketogenic diet, on the other hand, is distinguished by its extraordinarily high fat content, generally 70 percent to 80 percent, despite just a moderate protein consumption.
How Does It Work?
The ketogenic diet for weight reduction is based on the idea that by depriving the body of glucose, which is the major source of energy for all cells in the body and is obtained by ingesting carbohydrate meals, an alternative fuel called ketones is generated from stored fat (thus the name “keto”-genic). Because it cannot retain glucose, the brain requires the most glucose in a consistent supply, around 120 grammes per day. The body initially draws stored glucose from the liver and briefly breaks down muscle to release glucose while fasting or eating very little carbohydrate. If this goes on for 3-4 days and the body’s stored glucose is depleted, blood levels of an insulin-like hormone drop, and the body switches to fat as its major fuel. Ketone bodies are produced by the liver from fat and may be utilised in the absence of glucose.
Ketosis occurs when ketone bodies build in the blood. During periods of fasting (e.g., sleeping overnight) and highly vigorous activity, healthy people naturally experience moderate ketosis. The brain will use ketones for fuel, and healthy individuals will typically produce enough insulin to prevent excessive ketones from forming, according to proponents of the ketogenic diet. If the diet is carefully followed, blood levels of ketones should not reach a harmful level (known as “ketoacidosis”). The length of time it takes to enter ketosis and the quantity of ketone bodies that build in the blood depends on a variety of parameters, including body fat percentage and resting metabolic rate.
There is no such thing as a “standard” ketogenic diet with a set macronutrient ratio (carbohydrates, protein, fat). The ketogenic diet limits total carbohydrate intake to less than 50 grammes per day, which is less than a medium plain bagel, and can be as low as 20 grammes per day. Popular ketogenic publications recommend a total daily calorie intake of 70-80 percent fat, 5-10 percent carbohydrate, and 10-20 percent protein. This equates to roughly 165 grammes of fat, 40 grammes of carbohydrate, and 75 grammes of protein in a 2000-calorie diet. Because consuming too much protein might impede ketosis, the protein quantity on the ketogenic diet is maintained moderate in compared to other low-carb high-protein diets. Because protein’s amino acids may be converted to glucose, a ketogenic diet must include enough protein to maintain lean body mass, including muscle, while still causing ketosis.
There are many different types of ketogenic diets, but they all prohibit carbohydrate-rich meals. Starches from both refined and whole grains, such as breads, cereals, pasta, rice, and cookies; potatoes, maize, and other starchy vegetables; and fruit juices, to name a few. Beans, legumes, and most fruits are among the less obvious. Most ketogenic diets allow saturated fat-rich foods like fatty cuts of meat, processed meats, lard, and butter, as well as unsaturated fat-rich foods like nuts, seeds, avocados, plant oils, and oily fish. Ketogenic meal lists might differ and even clash depending on where you get your information.
According to the programmes, a ketogenic diet should be followed until the target weight loss is achieved. When this is accomplished, the diet can be followed for a few days a week or a few weeks each month, with alternate days allowing for a larger carbohydrate consumption.
The Research So Far
In the short term, the ketogenic diet has been proven to cause favourable metabolic alterations. Along with weight reduction, health indicators associated with obesity, such as insulin resistance, high blood pressure, and increased cholesterol and triglycerides, have improved. Low-carbohydrate diets, such as the ketogenic diet, are also gaining popularity as a treatment for type 2 diabetes. There are several ideas as to why the ketogenic diet helps weight reduction, however none have been proven in research:
- The high fat component of the diet has a satiating impact, resulting in less food cravings.
- A reduction in appetite-stimulating hormones like insulin and ghrelin when carbohydrate intake is limited.
- Ketone bodies, the body’s principal fuel source on a diet, have a direct hunger-reducing effect.
- Increased calorie expenditure as a result of the metabolic consequences of fat and protein conversion to glucose.
- Fat loss vs lean body mass is promoted, possibly due to lower insulin levels.
It may be difficult to stick to a particularly high-fat diet. Hunger, exhaustion, poor mood, irritability, constipation, migraines, and brain fog are all possible symptoms of severe carbohydrate restriction, which can last days to weeks. Though these unpleasant sensations may pass, being pleased with the limited range of foods available and being prohibited from normally delicious items such as a crisp apple or creamy sweet potato may bring new problems.
Long-term ketogenic diets have been linked to an increased risk of kidney stones and osteoporosis, as well as higher uric acid levels in the bloodstream (a risk factor for gout). If the ketogenic diet does not contain a range of suggested foods, nutritional shortages may occur. To maintain appropriate intakes of fibre, B vitamins, and minerals (iron, magnesium, zinc)—nutrients generally found in foods like whole grains that are banned from the diet—it is necessary to incorporate a daily variety of the authorised meats, fish, vegetables, fruits, nuts, and seeds in the diet.
There is currently a scarcity of studies on the ketogenic diet for weight loss. The majority of previous research had a limited number of participants, were short-term (12 weeks or less), and did not include control groups. A ketogenic diet has been proven to provide short-term weight reduction and improvements in total cholesterol, blood sugar, and blood pressure in certain persons. However, when compared to the results of traditional weight reduction regimens, these outcomes after a year are not significantly different.
Compliance may be challenging because to the elimination of numerous food categories and the possibility of unpleasant symptoms. The American Heart Association and the Dietary Guidelines for Americans both advocate avoiding foods high in saturated fat, which may have negative impacts on blood LDL cholesterol. However, you may change your diet to include more low-saturated-fat items like olive oil, avocado, nuts, seeds, and fatty fish.
Some people who have struggled to lose weight with traditional approaches may benefit from a ketogenic diet. Because of their genetic makeup and body composition, the exact ratio of fat, carbohydrate, and protein required to obtain health advantages varies by people. If one decides to begin a ketogenic diet, it is advised to consult with a physician and a dietitian to closely monitor any biochemical changes that occur after beginning the diet, as well as to develop a meal plan that is tailored to one’s current health conditions in order to avoid nutritional deficiencies or other health complications. Once you’ve lost weight, a dietician can advise you on how to reintroduce carbs.