Ketogenic Diet: Does It Work For Weight Loss?

The ketogenic diet, or keto diet, is a low-carbohydrate, high-fat eating plan that has been used for centuries to treat specific medical conditions. In the 1920s, the ketogenic diet was introduced as an effective treatment for epilepsy in children. The diet has also been tested and used in closely monitored settings for cancer, diabetes, polycystic ovary syndrome, and Alzheimer's disease. More recently, the keto diet has gained attention as a potential weight-loss strategy. The premise of the diet is that by depriving the body of glucose, its main source of energy, an alternative fuel called ketones is produced from stored fat. This state is called ketosis. While the keto diet has been shown to be effective for short-term weight loss, there is little evidence to support its use for long-term weight loss. Additionally, the keto diet can be challenging to maintain and may have negative side effects, including an increased risk of kidney stones and constipation.

Weight loss

The ketogenic diet is a popular approach to losing weight. It involves eating a very low amount of carbohydrates and replacing them with fat, which puts your body into a metabolic state called ketosis. In this state, your body becomes very efficient at burning fat for energy.

How it works

Ketogenic diets can cause a significant reduction in blood sugar and insulin levels. When you eat less than 50 grams of carbohydrates a day, your body eventually runs out of fuel (blood sugar) and starts to break down protein and fat for energy, which can lead to weight loss.

Effectiveness

The effectiveness of the ketogenic diet for weight loss has been demonstrated in several studies. One review of 13 studies found that people who followed a ketogenic diet lost 2 pounds more than those who followed a low-fat diet over one year. Another review of 11 studies showed that the ketogenic diet group lost 5 pounds more than the low-fat diet group after six months.

Comparison with other diets

The ketogenic diet may help you lose more weight in the first 3 to 6 months compared to some other diets. This could be because it takes more calories to change fat into energy than carbohydrates. It is also possible that the high-fat and high-protein content of the ketogenic diet makes people feel fuller, leading to reduced calorie intake.

Considerations

While the ketogenic diet can be effective for weight loss, it may not be suitable for everyone. It is important to consult with a healthcare professional before starting this or any other diet, especially if you have a health condition or are taking medication.

Additionally, the ketogenic diet can be challenging to follow due to its restrictive nature. It is important to plan meals in advance and ensure adequate fluid and electrolyte intake to counter potential side effects, such as the "`keto flu," which may include symptoms like nausea, fatigue, and dizziness.

Furthermore, while the ketogenic diet can lead to rapid weight loss, it may not be sustainable for everyone. Some people may find it difficult to maintain the diet long-term due to the limited food options and the potential for nutrient deficiencies.

The ketogenic diet can be an effective approach to weight loss, especially in the short term. However, it is important to consider the potential challenges and side effects and consult with a healthcare professional before starting this or any other diet.

Ketogenic diet and diabetes

The ketogenic diet has been used to help control diabetes since the 19th century. It is a low-carbohydrate, fat-rich eating plan that can change the way the body stores and uses energy, easing diabetes symptoms. The diet can improve blood glucose (sugar) levels while also reducing the need for insulin.

The ketogenic diet may be an option for people with type 2 diabetes who have difficulty controlling their symptoms. Many people feel better with fewer diabetic symptoms, and they may also be less dependent on medications. However, not everyone has success on this diet, as some may find the restrictions too difficult to follow over the long term.

There is also a risk of diabetic ketoacidosis (DKA) for people with type 1 or type 2 diabetes on the ketogenic diet. DKA is a medical emergency that can cause a diabetic coma. It is most prevalent in type 1 diabetes when blood glucose is too high and can arise from a lack of insulin. Although rare, DKA is possible in type 2 diabetes if ketones are too high.

The ketogenic diet is not suitable for everyone with diabetes. It is not recommended for women who are pregnant or lactating, people with or at risk for eating disorders, or people with renal disease.

The Mediterranean diet, a low-carb, moderately high-fat diet, has been found to be as effective as the ketogenic diet in controlling blood glucose in people with type 2 diabetes. The Mediterranean diet emphasizes vegetables, legumes, fruits, whole grains, olive oil, and fish. It may be a more sustainable option for people with diabetes or prediabetes.

Overall, the ketogenic diet may be beneficial for people with diabetes, but it is important to speak with a doctor before making any drastic dietary changes.

Ketogenic diet and epilepsy

The ketogenic diet has been used to control seizures in people with epilepsy since the 1920s. It is a high-fat, low-carbohydrate diet that is typically used for children whose seizures have not responded to medication. The diet is carefully monitored by a physician and a dietitian and is usually started in the hospital. The diet works by producing ketones in the body, which are formed when the body uses fat for energy instead of carbohydrates. Ketones can be detected in the urine, blood, and breath, and higher levels of ketones often lead to improved seizure control.

Several studies have shown that the ketogenic diet can reduce or prevent seizures in children whose seizures could not be controlled by medication. Over half of the children who go on the diet experience at least a 50% reduction in the number of seizures, and some children become seizure-free. The diet has been shown to be particularly helpful for certain types of epilepsy, including infantile spasms, Rett syndrome, tuberous sclerosis complex, and Dravet syndrome.

The ketogenic diet is not usually recommended for adults with epilepsy because the restricted food choices make it hard to follow. However, a modified version of the diet, called the modified Atkins diet, has been found to be effective and better tolerated for adults. This version of the diet has a less restrictive ratio of fat to carbohydrates and protein and does not restrict calories or fluids.

While the ketogenic diet can be effective in controlling seizures, it also has some potential side effects. These include high cholesterol levels, gastrointestinal symptoms such as constipation, diarrhea, and abdominal pain, and weight loss. It is important for individuals on the diet to be closely monitored by a healthcare team to manage any side effects and ensure adequate nutrition.

Ketogenic diet and Alzheimer's disease

Alzheimer's disease (AD) is the sixth-leading cause of death in the US, with around 6.2 million Americans living with the disease in 2021. It is characterised by a progressive cognitive and functional decline. The build-up of the protein beta-amyloid in the brain disrupts communication between neurons and ultimately kills brain cells.

The brain relies on glucose as its primary source of energy, but in people with AD, the brain is less able to use glucose for fuel. Ketogenic diets are currently being studied as a method to help reduce or prevent the onset of cognitive decline in Alzheimer's patients. The goal of a ketogenic diet is to reduce the reliance of the brain on glucose as fuel and instead use ketones.

Ketogenic Diet and Brain Function

Ketogenic diets are high-fat, low-carbohydrate diets that shift the body towards fat metabolism. Neurons cannot metabolise fats directly, but the liver converts fats into ketones, which can serve as a major energy source for neurons. During a typical Western diet, the concentration of the primary blood ketone, beta-hydroxybutyrate, supplies less than 5% of brain energy requirements. By contrast, a ketogenic diet induces a state of "physiological ketosis" in which beta-hydroxybutyrate provides a greater contribution to brain energy metabolism and its blood concentration exceeds 0.5-0.6 mmol/L.

Research has shown that a ketogenic diet can improve the cognitive abilities and quality of life of patients ranging from mild to severe AD. Several types of memory were improved as a result of the diet. The exact cause behind these improvements is still unknown and requires further research. However, the studies conducted so far mostly agree that once ketosis is reached, cognitive improvements are observed in patients ranging from mild to severe AD or mild to moderate cognitive impairment.

A pilot study, the Ketogenic Diet Retention and Feasibility Trial (KDRAFT), assessed the feasibility and cognitive effects of a ketogenic diet in individuals with AD. Ten participants with mild AD followed the ketogenic diet for three months, followed by a return to a normal diet for one month. Standard cognitive tests showed that cognitive scores significantly improved after the three-month intervention. Test scores returned to baseline after the one-month washout period.

Another randomised crossover trial examined the impact of a 12-week modified ketogenic diet in 26 patients with clinically confirmed diagnoses of AD. 21 patients (81%) completed the ketogenic diet, with only one withdrawal attributed to the diet. Patients on the ketogenic diet achieved sustained physiological ketosis and showed improvements in daily function and quality of life compared to patients on a usual diet.

Challenges and Future Directions

One challenge with the ketogenic diet is adherence, as some people may find it difficult to stick to the dietary restrictions. Additionally, the ketogenic diet may cause gastrointestinal issues, which can lead to dropout from the diet. Further research is needed to determine the long-term effects of a ketogenic diet on Alzheimer's disease and to establish the underlying mechanisms behind the observed cognitive improvements.

In conclusion, the ketogenic diet shows potential as a viable and effective treatment strategy for AD. However, larger and longer-term studies are needed to confirm its benefits and establish its role in the management of this debilitating disease.

Ketogenic diet and nutrient deficiencies

The ketogenic diet is a low-carbohydrate, high-fat eating plan that has been used to treat specific medical conditions and aid weight loss. While it has been shown to be effective for these purposes, there are associated health risks, including nutrient deficiencies.

The keto diet is very restrictive, and this can lead to an inadequate intake of essential vitamins, minerals, and phytochemicals. The diet typically reduces total carbohydrate intake to less than 50 grams a day and can be as low as 20 grams. This means that whole food groups are excluded, such as fruits, legumes, and whole grains, which are good sources of nutrients.

Potential nutrient deficiencies that can occur as a result of the keto diet include folate (B9), biotin (B7), selenium, choline, vitamins A, E, D, chromium, iodine, magnesium, and molybdenum.

To avoid nutrient deficiencies while on the keto diet, it is important to eat a variety of nutrient-dense foods, such as grass-fed meat, pastured chicken and pork, wild-caught fish, eggs, bone broth, colourful raw vegetables, and leafy greens. It is also beneficial to take supplements or choose a multivitamin that contains all the micronutrients that may be lacking in the diet.

Additionally, it is recommended to consult with a physician and a dietitian before starting the keto diet to ensure that any existing nutrient deficiencies are addressed and to create a meal plan that prevents further deficiencies.

Frequently asked questions