Keto And Calories: What's The Real Science?

The keto diet is a high-fat, low-carbohydrate, and moderate-protein diet. It works by creating a negative energy balance, forcing the body to use stored fat as an energy source. However, the keto diet only leads to weight loss when coupled with a calorie deficit. The body will only shed fat when it has a calorie deficit, regardless of whether carbohydrates are consumed or not. Therefore, keto works because of a calorie deficit.

Ketogenic diets are high-fat, low-carbohydrate and moderate-protein diets

The ketogenic diet is a high-fat, low-carbohydrate, and moderate-protein diet. It is designed to increase insulin sensitivity and promote weight loss. Insulin sensitivity refers to how responsive the body is to glucose from food. The body can efficiently use insulin to redistribute glucose from the blood with high insulin sensitivity. Conversely, low insulin sensitivity (insulin resistance) impairs the body's ability to utilise glucose for energy effectively.

When carbohydrates are consumed, the body processes them with insulin, which transports blood glucose into fat stores, leaving an individual feeling hungry. On the other hand, when very few carbohydrates are consumed, the body starts running on ketones, which the liver manufactures from fat. This results in reduced hunger and less fat accumulation.

The ketogenic diet involves replacing most of the calories from carbohydrates and protein (approximately 80%) with fat. Carbohydrates are the primary fuel source for cells, so a low-carbohydrate diet forces the body to rely on its reserves, known as glycogen. As glycogen levels deplete, the body increasingly depends on fat and its by-products, called ketone bodies, for energy.

By increasing the proportion of fats in the diet, the body enters a state of ketosis, using ketone bodies for fuel. This state of ketosis also affects hunger hormones (ghrelin and leptin), reducing appetite and leading to decreased calorie consumption. Additionally, proponents of the ketogenic diet claim that dietary fat is a more efficient energy source than carbohydrates. However, it is important to note that completely eliminating carbohydrates can negatively impact sports performance, especially at higher intensities.

The ketogenic diet has gained popularity due to its perceived benefits for weight loss and overall health. Studies have shown it to be particularly effective for obese patients. One of the key advantages of the keto diet is its ability to suppress appetite, making it easier to consume less energy without feeling excessively hungry. This effect, combined with stable blood sugar levels due to reduced carbohydrate intake, helps individuals adhere to a calorie deficit, which is necessary for weight loss.

In conclusion, the ketogenic diet, with its high-fat, low-carbohydrate, and moderate-protein composition, promotes weight loss by enhancing insulin sensitivity, reducing hunger, and stabilising blood sugar levels. However, it is important to consult with a healthcare professional before starting any diet, especially one as restrictive as the ketogenic diet.

The keto diet restricts carbohydrates, while a calorie deficit works with any food group

The keto diet and a calorie deficit approach are two distinct methods for achieving weight loss. They differ in the specific mechanisms they employ, but ultimately, both aim to create a negative energy balance, prioritising the consumption of nutrient-dense and minimally processed foods.

The ketogenic diet, or keto, is a high-fat, low-carbohydrate, and moderate-protein diet. It restricts carbohydrates, forcing the body to rely on fat reserves and by-products called ketone bodies for energy. This state of relying on ketone bodies is known as ketosis. Keto can lead to reduced appetite and increased insulin sensitivity, making it an effective tool for weight loss and managing conditions like Type 2 diabetes and Non-alcoholic Fatty Liver Disease. However, it may not be suitable for everyone due to potential drawbacks such as dehydration, bad breath, and impaired sports performance.

On the other hand, a calorie deficit approach focuses on the number of calories consumed, regardless of the food group. It is based on the principle of creating a negative energy balance by consuming fewer calories than the body requires. This approach is more flexible and allows for a greater variety of food choices, making it easier to sustain in the long term.

While keto can be effective for weight loss, it is important to understand that it is the calorie deficit created by the diet that leads to weight loss, not the state of ketosis alone. Even when following a keto diet, maintaining a calorie deficit is crucial for shedding fat. Combining keto with a calorie deficit can enhance weight loss efforts, as keto may make it easier to sustain a deficit due to its appetite-suppressing effects.

In summary, the keto diet restricts carbohydrates, while a calorie deficit approach can be applied to any food group. Both methods aim to create a negative energy balance but differ in their specific mechanisms. The calorie deficit approach offers more flexibility and variety in food choices, while keto may provide additional health benefits beyond weight loss for certain individuals. Ultimately, the choice between the two depends on individual preferences, health goals, and sustainability.

The keto diet can help with Type 2 diabetes, Alzheimer’s disease and Non-alcoholic Fatty Liver Disease

The keto diet is a high-fat, low-carbohydrate, and moderate-protein diet. It helps increase insulin sensitivity and promote weight loss. The diet was initially created in the 1920s as a treatment for epilepsy, but its effects are now being studied for other conditions, including Type 2 diabetes, Alzheimer's disease, and Non-alcoholic Fatty Liver Disease.

Type 2 Diabetes

People with Type 2 diabetes can benefit from the keto diet, but there are some risks associated with it. The keto diet can improve blood glucose (sugar) levels and reduce the need for insulin. However, it is important to carefully monitor blood glucose and ketone levels as there is a risk of developing diabetic ketoacidosis (DKA) if ketone levels get too high. Some studies have shown that the keto diet can lead to greater improvements in glycemic control and medication reduction compared to other diets.

Alzheimer's Disease

The keto diet may also be beneficial for Alzheimer's disease. Alzheimer's is characterised by insulin resistance in the brain, which hampers the uptake of glucose for fuel. The keto diet can increase the brain's use of ketones for fuel, which may improve cognitive function. Some studies have shown that the keto diet can lead to improvements in memory and cognitive tests in people with Alzheimer's disease or mild cognitive impairment.

Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a condition where fat accumulates in the liver due to obesity, insulin resistance, and other factors. The keto diet can help control obesity and insulin resistance, thereby reducing fat accumulation in the liver. Studies have shown that the keto diet can reduce liver fat and inflammation, which may help treat NAFLD.

Overall, the keto diet has potential benefits for Type 2 diabetes, Alzheimer's disease, and Non-alcoholic Fatty Liver Disease. However, it is important to note that the keto diet may not be suitable for everyone and should be undertaken with medical supervision.

The keto diet can be an effective appetite suppressant

Ketogenic diets have been shown to be very effective, especially for obese patients. The keto diet is a high-fat, low-carbohydrate, and moderate-protein diet, which helps to increase insulin sensitivity and promote weight loss. By increasing the amount of fat in your diet, your body will enter a state of ketosis, meaning it relies on ketone bodies for fuel.

The keto diet can also help with Type 2 diabetes, Alzheimer's disease, and Non-alcoholic Fatty Liver Disease. Additionally, it can make it easier to eat fewer calories and sustain a deficit, as it acts as an effective appetite suppressant for many people. However, it's important to note that some hunger when losing weight is normal, even on the keto diet.

Furthermore, if you're working out a lot, you may find that you get hungrier, especially if you're doing a lot of cardio. In that case, you might want to try lifting weights or a combination of resistance training and some cardio, which can help create bigger deficits and put on muscle, aiding in fat burning.

While the keto diet can be effective, it's not necessary to completely eliminate carbohydrates. Completely cutting out carbs can lead to a lack of vitamins, minerals, fiber, and phytochemicals found in fruits, vegetables, and whole grains. Additionally, research shows that a diet with little-to-no carbs can result in poor sports performance. Therefore, it's important to include some high-quality fats from whole-food sources, such as nuts, seeds, avocados, olives, fatty fish, and dairy. These foods provide higher-quality fats and deliver vitamins and minerals necessary for overall health and activity.

The keto diet can lead to reduced postprandial glycemia (lower sugar levels after meals)

The keto diet has been shown to be effective in lowering fasting blood glucose levels in people with type 2 diabetes. A meta-analysis of single-arm trials found that the keto diet decreased fasting blood glucose levels by 1.29 mmol/L and glycated hemoglobin (HbA1c) by 1.07. Another meta-analysis comparing the keto diet to any diet recommended for people with type 2 diabetes found that the keto diet produced a more significant reduction in HbA1c, body weight, and triglycerides, and a greater increase in high-density lipoprotein cholesterol (HDL-c) compared to the other diets.

The keto diet's restriction of digestible carbohydrates also decreases hepatic glycogen and de novo synthesis of fatty acids in hepatocytes, which enhances whole-body fat catabolism, resulting in reduced liver and blood lipids. The keto diet has been shown to improve the lipoprotein profile, at least over a period of about a year, independently of weight loss.

The keto diet has also been found to reduce intrahepatic triglyceride content in people with non-alcoholic fatty liver disease (NAFLD), which is associated with type 2 diabetes. A study found that a low-carbohydrate ketogenic diet (LCKD) decreased intrahepatic triglyceride content by 30% in NAFLD individuals after just six days, and markedly improved insulin sensitivity.

In addition to its effects on glycemic control, the keto diet has been found to have other beneficial effects on health. It has been shown to be effective for weight loss, at least in the short to medium term, and has been found to improve insulin sensitivity through its effects on fat and weight loss. The keto diet has also been found to reduce oxidative stress and have anti-inflammatory effects, which may also contribute to improved insulin sensitivity.

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