Keto Diet: How Does It Affect My Body?

The keto diet is a popular weight-loss strategy that involves eating a high-fat, moderate-protein, and low-carbohydrate diet. It works by forcing the body into a metabolic state called ketosis, where it burns fat for energy instead of glucose. Typically, carbohydrates in the diet provide most of the fuel the body needs, but when carb intake is very low, the body turns to fat as its main fuel source. This process can help with weight loss, increase energy, and treat chronic illnesses like epilepsy and type 2 diabetes. However, the keto diet is strict and difficult to maintain, and it may have side effects like keto breath, constipation, and keto flu, which includes symptoms like upset stomach, headache, and fatigue.

Ketosis: a metabolic state where the body burns fat for energy instead of glucose

Ketosis is a metabolic state where the body burns fat for energy instead of glucose. Typically, the body uses blood sugar (glucose) derived from carbohydrates as its primary energy source. However, when carb intake is very low, the body switches to burning fat for energy, resulting in ketosis. This metabolic state can be achieved through the ketogenic (keto) diet, which is high in fat, moderate in protein, and low in carbohydrates.

During ketosis, the body breaks down fat and produces ketones, or ketone bodies, which become the main source of energy for the body and brain. The fat used to create ketones can come from dietary sources or the body's fat stores. As the body's glucose and insulin levels decrease, the liver increases ketone production to ensure adequate energy supply for the brain, leading to high ketone levels in the blood during ketosis.

The keto diet aims to induce ketosis by reducing carbohydrate intake and teaching the body to burn fat for fuel instead. This typically involves limiting carbohydrates to less than 50 grams per day, which can be challenging as many nutrient-rich foods like whole grains, fruits, and vegetables are high in carbs. The keto diet has been associated with potential weight loss, increased energy, and the management of certain chronic illnesses.

However, it is important to note that the keto diet can be difficult to follow and may have side effects such as "keto" breath, constipation, and "keto flu," which includes symptoms like upset stomach, headache, and fatigue. Additionally, the high-fat content of the keto diet, particularly saturated fats, has been linked to an increased risk of heart disease. Therefore, it is recommended to consult a healthcare professional before starting the keto diet to ensure it is suitable for your individual needs.

Weight loss: keto can help with weight loss, but it's not sustainable

The keto diet can help with weight loss, but it is not a sustainable, long-term solution.

The keto diet is a metabolic state that occurs when your body burns fat for energy instead of glucose. Typically, your body uses blood sugar (glucose) as its key energy source, which comes from eating carbohydrates (carbs). On the keto diet, your body uses fat as its main fuel source, and you get very few carbs.

The keto diet is high in fat, moderate in protein, and low in carbs. The standard keto diet consists of 70% to 80% fats, 10% to 20% proteins, and 5% to 10% carbohydrates. To achieve ketosis, the diet requires you to eat 75% of your calories from fat, compared to 20-35% on a normal diet. It also restricts carbs to 5% of your calories, which is about 20-50 grams per day, and 15% of calories from protein.

The keto diet can help with weight loss because it reduces your hunger. When you eat a lot of carbohydrates, your insulin levels rise and then fall quickly. This decrease in insulin tells your brain to ask for more food. On the keto diet, your insulin levels stay pretty level, so you don't get those hunger pangs. Also, because fats and proteins take longer to digest, you feel fuller for longer.

However, the keto diet is not a sustainable way to lose weight. It is extremely strict and difficult to maintain. It can be hard to get enough of the right kinds of fat, and it is easy to fall back on saturated fats like lard, butter, and coconut oil, which can increase your risk of heart disease. It also restricts healthy foods like fruits, vegetables, whole grains, and low-fat dairy, which can help with long-term weight loss and overall health.

The keto diet can also have some unpleasant side effects, like "keto flu," which includes symptoms such as an upset stomach, headache, fatigue, and constipation. It can also cause bad breath, high cholesterol, and fuzzy thinking and mood swings.

Overall, while the keto diet may help with short-term weight loss, it is not a sustainable or healthy way to lose weight and keep it off. It is always best to consult your doctor or a registered dietitian before starting any new diet.

Increased energy: keto can increase focus and energy

The keto diet can increase your energy and focus by changing the way your body uses food. Typically, carbohydrates in your diet provide most of the fuel your body needs. The keto diet, however, reduces the number of carbs you eat and teaches your body to burn fat for fuel instead.

When you eat a diet high in carbohydrates, your insulin levels rise after you eat, but then quickly fall. This decrease in insulin alerts the hunger centre of your brain to provide more food. Your body will often “crave” something to bring those insulin levels back up, and that choice feeds into a cycle of high carbohydrates as the major source of calories in a Western diet.

On the keto diet, your insulin levels stay pretty level, at a steady, low level. So, you don't get the fluctuations in insulin. And when you're not getting the fluctuations in insulin, that can reduce your hunger.

Because fats and proteins take the body longer to digest, you may feel fuller for longer. “The food sits in the stomach; it doesn't empty out of the stomach as quickly, so you feel fuller,” said Russell H. Swerdlow, M.D., professor of neurology, biochemistry and physiology in the KU School of Medicine and director of the University of Kansas Alzheimer’s Disease Research Center.

Ketosis, the metabolic state that occurs when your body burns fat for energy instead of glucose, has been shown to increase your focus and energy. Research suggests your brain works more efficiently on ketones than on glucose.

However, the keto diet is not without its drawbacks. It can be difficult to follow and can produce side effects including “keto” breath, constipation, and "keto flu", which includes symptoms such as an upset stomach, headache, and fatigue.

Treating chronic illness: keto can help treat chronic illnesses like epilepsy and type 2 diabetes

The ketogenic diet can be used to treat chronic illnesses like epilepsy and type 2 diabetes.

Epilepsy

The ketogenic diet has been used to treat epilepsy since the 1920s. It is usually recommended for children whose seizures have not responded to medication. The diet is high in fat and low in carbohydrates, which causes the body to produce ketones, which are used for energy instead of glucose. The diet can reduce or even prevent seizures by altering the "excitability" of the brain. 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 usually started in the hospital, with the child fasting under medical supervision for 18-24 hours before slowly introducing the diet. The ketogenic diet has been shown to reduce seizures in many children, with over half experiencing at least a 50% reduction in seizure frequency. Some children, around 10-15%, even become seizure-free.

Type 2 Diabetes

The ketogenic diet can also be used to treat type 2 diabetes. The diet can potentially change the way the body stores and uses energy, easing diabetes symptoms. It may improve blood glucose (sugar) levels while also reducing the need for insulin. A 2008 study found that participants who followed the ketogenic diet saw greater improvements in glycemic control and medication reduction compared to those who followed a low-glycemic diet. Another study found that a ketogenic diet can lead to more significant improvements in blood sugar control, A1C, weight loss, and discontinued insulin requirements than other diets. The ketogenic diet may be particularly beneficial for people with type 2 diabetes who are overweight, as it can help with weight loss. However, it is important to note that the diet can also lead to an increase in "bad" LDL cholesterol, which is linked to heart disease. Therefore, it is important to speak with a doctor before starting the ketogenic diet to ensure it is a safe and appropriate treatment option.

Potential side effects: keto flu, bad breath, constipation, and high cholesterol

The keto diet can cause a range of side effects, including keto flu, bad breath, constipation, and high cholesterol.

Keto flu is a group of symptoms that may appear two to seven days after starting a ketogenic diet. Symptoms can include headache, foggy brain, fatigue, irritability, nausea, upset stomach, difficulty sleeping, and constipation. While not a medically recognised condition, it can be unpleasant and affect your day-to-day life. Staying hydrated and eating more vegetables can help alleviate these symptoms.

Bad breath, or "keto breath", is another common side effect of the keto diet. This is caused by the production of ketones, specifically acetone, which is also an ingredient in nail polish remover. Increasing water intake and lowering protein consumption may help reduce the taste and smell of keto breath.

Constipation is also a frequent side effect of the keto diet, as the reduction in carbohydrate intake can lead to digestive issues. The keto diet restricts high-carb, fibre-rich foods like fruits, whole grains, and starchy vegetables, which can result in hard and lumpy stools that are difficult to pass. To prevent constipation, it is recommended to introduce the keto diet gradually and ensure adequate hydration.

Finally, the keto diet has been associated with an increase in "bad" LDL cholesterol, which is a risk factor for heart disease. This is due to the high content of saturated fats encouraged on the keto diet.

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