Keto Body: Does The Science Add Up?

The keto diet is a low-carb, high-fat diet that aims to force the body into using a different type of fuel. Instead of relying on glucose from carbohydrates, the keto diet relies on ketone bodies – a type of fuel that the liver produces from stored fat. The diet is advertised as a weight-loss solution, but it is actually a medical diet that comes with serious risks and should not be treated as an experiment. While it can be beneficial for short-term weight loss, it is not suitable for everyone and can lead to nutrient deficiencies, liver and kidney problems, constipation, and fuzzy thinking and mood swings.

Ketogenic diet and weight loss

The ketogenic diet is a low-carb, high-fat diet that has gained popularity for its potential to promote weight loss. It involves drastically reducing carbohydrate intake and replacing it with fat. This reduction in carbs puts the body into a metabolic state called ketosis, where it burns fat for energy instead of glucose.

When following a ketogenic diet, the body enters a state of ketosis, which is an elevation of ketone levels in the body. Normally, the body uses blood sugar (glucose) derived from carbohydrates for energy. However, during ketosis, the body relies on ketones produced from burning fat in the liver as its main energy source.

Weight Loss

The ketogenic diet is an effective way to lose weight and lower risk factors for disease. Research shows that the ketogenic diet may be as effective for weight loss as a low-fat diet. A review of 13 studies found that a ketogenic diet was slightly more effective for long-term weight loss compared to a low-fat diet. People on the keto diet lost an average of 2 pounds (0.9 kg) more than those on a low-fat diet.

Additionally, the ketogenic diet is very filling, so weight loss can occur without intentionally restricting calories. The high fat and moderate protein content of the diet help reduce appetite, leading to a natural reduction in food intake.

Other Health Benefits

The ketogenic diet has been associated with various health benefits beyond weight loss. These include:

• Improved blood sugar management: The diet can help lower blood sugar and improve insulin sensitivity, which is especially beneficial for people with type 2 diabetes or prediabetes.
• Neurological benefits: The diet was originally introduced to treat epilepsy and reduce seizures. It has also been studied for its potential benefits in Alzheimer's disease, Parkinson's disease, and brain injuries.
• Heart health: The keto diet may improve risk factors for heart disease, including lowering blood pressure, improving HDL ("good") cholesterol, and reducing triglycerides.
• Cancer treatment: The diet is being explored as a potential additional treatment for cancer, as it may help slow tumour growth.

Side Effects and Risks

While the ketogenic diet offers several potential benefits, it also has some side effects and risks. These include:

• "Keto flu": In the initial stages of the diet, people may experience fatigue, weakness, nausea, digestive issues, and headaches. These symptoms typically resolve within a few days to a week.
• Dehydration and electrolyte imbalances: The keto diet can lead to increased thirst and dehydration, especially during the early stages. It may also cause electrolyte imbalances, which can result in muscle cramps and spasms.
• Constipation: The low fibre content of the diet can lead to constipation.
• Nutrient deficiencies: The restrictive nature of the diet may lead to deficiencies in micronutrients, including selenium, magnesium, phosphorus, and vitamins B and C.
• High cholesterol: The diet is associated with an increase in "bad" LDL cholesterol, which is a risk factor for heart disease.
• Kidney problems: The high protein content of the diet may overload the kidneys, leading to potential kidney issues.
• Liver problems: The high amount of fat metabolized on the keto diet can worsen existing liver conditions.

The ketogenic diet can be an effective tool for weight loss and improving certain health markers. However, it should be approached with caution and preferably under medical supervision due to its potential side effects and risks. It is not a sustainable or suitable diet for everyone, and long-term adherence may be challenging.

Ketogenic diet and diabetes

The ketogenic diet has been shown to be effective in managing type 2 diabetes. It can help improve blood glucose (sugar) levels and reduce the need for insulin. However, it is important to note that the ketogenic diet is high in fat, and people with type 2 diabetes are often overweight, so it may seem counterintuitive to recommend a high-fat diet.

The key to the ketogenic diet is that it aims to have the body use fat for energy instead of carbohydrates or glucose. This means that most of the energy comes from fat, with very little coming from carbohydrates. It is important to note that this does not mean increasing your consumption of saturated fats. Heart-healthy fats are crucial to sustaining overall health. Some healthy foods that are commonly eaten on the ketogenic diet include olives, olive oil, nuts, and nut butters.

The ketogenic diet can help decrease blood glucose levels, which is important for managing type 2 diabetes. Carbohydrates turn into sugar, and consuming large quantities can cause blood sugar spikes. By switching the focus to fat, some people with type 2 diabetes experience reduced blood sugar.

It is important to note that the ketogenic diet comes with risks and should be discussed with a doctor before making any drastic dietary changes. One of the risks is the possibility of low blood sugar, or hypoglycemia, which can be dangerous if not carefully managed. Additionally, the ketogenic diet can lead to an increase in ketones in the blood, which may increase the risk of developing diabetic ketoacidosis (DKA). DKA is a medical emergency and can be life-threatening.

While the ketogenic diet may be beneficial for managing type 2 diabetes, it requires careful monitoring by a doctor. Both blood glucose and ketone levels need to be regularly checked to ensure the diet is not causing any negative effects. Even if symptoms improve, regular blood glucose monitoring is still important for type 2 diabetes management.

There is also research that supports the effectiveness of other dietary approaches, such as a plant-based diet or the Mediterranean diet, in managing type 2 diabetes. These diets emphasize the consumption of vegetables, legumes, fruits, whole grains, and healthy fats. Ultimately, the best dietary approach for managing type 2 diabetes may vary depending on individual needs and should be determined in consultation with a doctor and dietitian.

Ketogenic diet and epilepsy

The ketogenic diet has been used to treat epilepsy since the 1920s. It is a high-fat, low-carbohydrate diet that helps to control seizures in some people with epilepsy, especially those whose seizures have not responded to medication. The diet is usually recommended for children, as it is stricter and harder for adults to follow.

The ketogenic diet is carefully monitored by a physician and a dietitian, and often carried out in hospital. It involves drastically reducing carbohydrate intake and replacing it with fat. This reduction in carbs puts your body into a metabolic state called ketosis, where the body uses fat for energy instead of carbohydrates. Ketones are formed when the body uses fat for energy, and higher ketone levels are often linked to improved seizure control.

Several studies have shown that the ketogenic diet does reduce or prevent seizures in many 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 their seizures, and some become seizure-free.

The ketogenic diet has been shown to be particularly helpful for some epilepsy conditions, including infantile spasms, Rett syndrome, tuberous sclerosis complex, Dravet syndrome, Doose syndrome, and GLUT-1 deficiency.

The diet is not usually recommended for adults, as it is restrictive and hard to follow. However, the Modified Atkins Diet (MAD) is a less restrictive form of the ketogenic diet that has been shown to be effective in treating epilepsy in adults and adolescents. It has a 1:1 ratio of fat to carbohydrates and protein, and contains around 65% fat, 25% protein, and 10% carbohydrates.

The ketogenic diet is not recommended as a primary anti-seizure option because patients often find it hard to stick to due to its strict requirements and potential side effects like nausea, constipation, and fatigue. However, it can be beneficial for people with epilepsy who do not respond to medication.

Ketogenic diet and cardiovascular health

The ketogenic diet is a very low-carb, high-fat diet that has been associated with several health benefits, including weight loss, improved insulin sensitivity, and reduced risk of certain diseases. However, its effects on cardiovascular health are still a subject of debate. While some studies suggest potential benefits, others indicate possible negative consequences. Here is an in-depth look at the relationship between the ketogenic diet and cardiovascular health:

Weight Loss and Cardiovascular Risk Factors

The ketogenic diet has been shown to promote weight loss, which can positively impact cardiovascular health. Obesity is a significant risk factor for cardiovascular disease, and weight loss can help reduce this risk. In both rodents and humans, the ketogenic diet has been found to increase energy expenditure, leading to decreased weight gain or weight loss. This effect is particularly beneficial for individuals who are overweight or obese, as even moderate weight loss can have metabolic benefits.

However, it is important to note that long-term studies are needed to fully understand the sustainability of weight loss on the ketogenic diet. Some studies suggest that weight loss may not be maintained over time, and yo-yo dieting can have negative consequences for heart health.

In addition to weight loss, the ketogenic diet has been linked to improvements in other cardiovascular risk factors. These include reduced blood pressure, lower triglyceride levels, and improved lipid profiles, including increased HDL ("good") cholesterol. These positive effects have been observed in both short-term and long-term studies.

Potential Negative Effects

Despite these potential benefits, the ketogenic diet may also have some negative consequences for cardiovascular health. One of the main concerns is the high intake of saturated fats, which are known to increase the risk of heart disease. The diet's restriction of carbohydrates and encouragement of saturated fats from oils, lard, butter, and cocoa butter can be detrimental to heart health.

In rodents, the ketogenic diet has been associated with the development of non-alcoholic fatty liver disease (NAFLD) and insulin resistance, both of which are risk factors for cardiovascular disease. While these findings have not been consistently reported in human studies, there is a need for further research to fully understand the long-term effects of the ketogenic diet on the liver and insulin sensitivity.

Additionally, the ketogenic diet has been linked to increased levels of LDL ("bad") cholesterol in about 30% of people. While the average increase in LDL-C levels is typically small to moderate, some individuals may experience a dramatic rise, which could negatively impact cardiovascular health.

Overall Impact on Cardiovascular Health

The overall impact of the ketogenic diet on cardiovascular health remains uncertain. While some studies suggest potential benefits, such as weight loss and improved lipid profiles, others indicate possible negative effects, including increased LDL-C levels and the development of NAFLD and insulin resistance in rodents. The specific foods chosen on the ketogenic diet also play a crucial role, with animal-based sources of fat and protein being associated with a higher risk of type 2 diabetes.

Due to these conflicting findings, it is essential to consult with a healthcare professional before starting the ketogenic diet, especially for those with existing heart disease or risk factors. The diet may be effective under close supervision for a select group of individuals, but it is not suitable for everyone. For optimal heart health, many cardiologists recommend less restrictive dietary approaches, such as the Mediterranean diet, which emphasizes good fats, fiber-rich whole grains, and a variety of fruits, vegetables, legumes, and healthy protein sources.

Ketogenic diet and Alzheimer's disease

The ketogenic diet has been proposed as a potential approach to treating 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. It is characterised by a progressive cognitive and functional decline.

The brain typically relies on glucose as its primary energy source, but in people with AD, the brain is less able to use glucose for fuel. Ketogenic diets are high-fat, low-carb diets that shift the body towards fat metabolism. Neurons cannot metabolise fats directly, but the liver converts fats into ketones, which can be used as an alternative energy source for the brain.

Several studies have investigated the effects of a ketogenic diet on patients with AD, with promising results. One study found that a ketogenic diet improved the cognitive abilities and quality of life of patients with mild to severe AD. Another study found that a 12-week modified ketogenic diet improved daily function and quality of life in patients with AD, compared to a usual diet. Additionally, a pilot study showed that a three-month ketogenic diet intervention significantly improved cognitive scores in participants with mild AD.

However, there are also studies that showed no cognitive improvements in patients with mild to moderate AD who followed a ketogenic diet. More research is needed to fully understand the effects of a ketogenic diet on AD and to determine the best type of ketogenic diet for improving cognitive function in these patients.

Potential Mechanisms

The build-up of the protein beta-amyloid in the brain, which disrupts communication between neurons and kills brain cells, is believed to be a cause of AD. However, Dr Russell Swerdlow's research suggests that amyloid plaques may be a result, rather than a cause, of AD, and that defects in brain energy metabolism may be the underlying cause.

Since AD may reduce the number and function of glucose transporters in the brain, ketones could provide an alternative energy source. Ketogenic diets have been found to upregulate mitochondria biogenesis and induce the expression of genes associated with the citric acid cycle and respiratory chain, increasing neuron energy production.

Practical Considerations

It is important to note that the ketogenic diet may not be suitable for everyone, and it can have some side effects. Additionally, the diet can be challenging to adhere to, especially for those with AD or cognitive impairments. Studies have reported high dropout rates, with gastrointestinal issues being a common reason for discontinuation.

Further research is needed to determine the long-term effects of the ketogenic diet and to establish its effectiveness as a treatment strategy for AD. Larger and longer-term studies are required to fully understand the potential benefits and risks of this dietary approach for patients with AD.

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