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The ketogenic (“keto”) diet is a high-fat, low-carbohydrate eating strategy designed to promote weight loss, as well as improve mental clarity, and enhance energy levels. By drastically cutting down on carbohydrates and increasing fat and protein intake, the body enters a metabolic state that is referred to as “ketosis”, where fat is used as the primary energy source instead of carbohydrates. The main aim of the keto diet is to reduce body fat and improve overall metabolic health. 

In a typical keto diet, macronutrient distribution is about 55% to 60% fat, 30% to 35% protein, and 5% to 10% carbohydrates, equating to 20 to 50 grams of carbs per day on a 2000-calorie diet. Avoiding sugars and starches is crucial for maintaining ketosis and achieving the diet’s benefits.

Proteins

Protein intake should be moderate to support muscle maintenance without disrupting ketosis.

Examples:

  • Beef: Provides high-quality protein and essential nutrients like iron and B vitamins.
  • Pork: A versatile protein source with cuts like bacon, pork chops, and ribs.
  • Poultry: Chicken and turkey are lean protein sources rich in vitamins and minerals.
  • Fish: Fatty fish like salmon and mackerel are excellent sources of omega-3 fatty acids.
  • Eggs: Packed with protein and healthy fats, they are versatile and nutrient-dense.

Fats

Fats are the primary energy source on a ketogenic diet. They help keep you full and provide the necessary fuel for ketosis. Examples:

  • Coconut Oil: Rich in medium-chain triglycerides (MCTs), which are quickly converted into ketones.
  • Avocado: High in healthy monounsaturated fats and fiber.
  • Olive oil: Contains antioxidants and healthy fats.
  • Dark chocolate: Choose varieties with high cocoa content and low sugar.
  • Nuts and seeds: Almonds, walnuts, chia seeds, and flaxseeds provide healthy fats and fiber.

Low-carb vegetables

These vegetables are low in carbohydrates and high in fiber, vitamins, and minerals.

Examples:

  • Lettuce: Ideal for salads and wraps, providing vitamins A and K.
  • Cucumber: Hydrating and low in carbs, perfect for snacking.
  • Tomato: Rich in antioxidants and low in carbohydrates.
  • Watercress: A nutrient-dense leafy green.
  • Endive: Crisp and low in carbs, great for salads and appetizers

High-carb vegetables (in moderation)

These vegetables have more carbohydrates and should be consumed in limited quantities.

Examples:

  • Yam: A good source of fiber and vitamins, but higher in carbs.
  • Zucchini: Lower in carbs than other high-carb vegetables, versatile in recipes.
  • Chayote: Low in carbs and can be used in various dishes.
  • Collard greens: Nutrient-rich and high in fiber.
  • Spinach: Nutrient-dense, with more carbs than low-carb vegetables.

Foods to avoid

Foods high in sugars and starches can disrupt ketosis and should be avoided.

Examples:

  • Sugary foods: Ice cream, cakes, candies.
  • Starches: Rice, pasta, potatoes.
  • Low-fat products: Often contain added sugars and lack healthy fats.
  • Bubble tea: High in sugar and carbs.

The keto diet’s impact on mental health is noteworthy. Ketosis provides a steady energy supply to the brain, potentially enhancing cognitive function and mental clarity. Some research suggests that the diet may help stabilize mood and reduce symptoms of anxiety and depression, thanks to its anti-inflammatory effects and consistent energy delivery. 

Comparison of before and after keto diets among hospitalized patients:

Outcome MeasureBefore KDAfter KDImprovement
Schizophrenia Symptoms91.4 (PANSS)49.3 (PANSS)100% improvement
Depression Symptoms (HAM-D)25.47.7100% improvement
Depression Symptoms (MADRS)29.610.1100% improvement
Illness Severity (CGI-S)4.92.043% remission

The table demonstrates that a ketogenic diet led to significant improvements in depression and psychosis symptoms among hospitalized patients. Additionally, the diet showed potential in reducing illness severity, as indicated by improvements in CGI-S scores.

The ketogenic diet, renowned for its high-fat, low-carbohydrate approach, not only offers substantial physical health benefits such as weight loss and improved metabolic health but also positively impacts mental well-being. 

Enhanced alertness and contentedness

Individuals on a ketogenic diet often report feeling more alert and content. The steady energy supply from ketones, which are a more efficient fuel for the brain than glucose, helps prevent mental fatigue and brain fog. Enhanced alertness can improve focus and productivity, while increased contentedness contributes to overall emotional well-being.

Increased calmness

The ketogenic diet has been associated with a noticeable calming effect, which can be beneficial for managing conditions like anxiety and bipolar disorder. This effect may be related to the diet’s influence on GABA (gamma-aminobutyric acid) levels, an inhibitory neurotransmitter that helps calm the nervous system and reduce nervousness and agitation.

Reduced stress

Both cognitive and emotional stress levels tend to decrease on a ketogenic diet. Cognitive stress relates to mental tasks and problem-solving, while emotional stress involves feelings of tension and anxiety. The reduction in stress may be linked to the diet’s ability to stabilize blood sugar levels and reduce inflammation, both of which can negatively impact stress levels. 

Improved mood

Adopting a ketogenic diet can lead to significant reductions in symptoms of depression and anxiety. This improvement is likely due to several factors, including the stabilization of blood sugar levels, a reduction in inflammatory markers, and increased GABA levels. These combined effects contribute to a more stable and positive mood, offering potential benefits for those with mood disorders.

Loneliness

There is some evidence to suggest that a ketogenic diet might reduce feelings of loneliness, although this improvement is not consistent across all measures. While some individuals may experience less loneliness, it is not a universal benefit of the diet.

Enhanced cognitive function

The ketogenic diet may improve cognitive function, particularly in individuals with neurodegenerative diseases like Alzheimer’s. Its neuroprotective effects may help maintain cognitive abilities and slow the progression of cognitive decline.

The ketogenic diet offers a range of health benefits that extend beyond weight loss, showing potential as a therapeutic option for various mental health disorders, neurological conditions, and chronic diseases.

Schizoaffective disorder

The ketogenic diet shows promise in alleviating symptoms of schizoaffective disorder. Individuals following this diet have reported significant improvements in both mood and psychotic symptoms, with some achieving symptom remission within a month. Additionally, this diet has helped reduce the need for psychotropic medications, offering a potential complementary treatment option for managing this complex disorder.

Bipolar disorder

For those with bipolar disorder, the ketogenic diet has been associated with improved mood stability and reduced anxiety. Reports indicate that individuals adhering to the diet experience fewer mood swings and a decrease in anxiety symptoms. The diet’s ability to stabilize blood sugar levels and its anti-inflammatory properties are believed to contribute to these positive outcomes. 

Epilepsy

Originally developed in the 1920s to treat epilepsy, particularly in children, the ketogenic diet has been highly effective in reducing seizure frequency and severity. Many children and adults with drug-resistant epilepsy have experienced significant improvements while on the diet. The diet is believed to work by altering the brain’s energy source from glucose to ketones, which stabilizes neuronal activity and reduces seizure activity.

Heart disease

For heart disease, the ketogenic diet offers multiple benefits. By improving lipid profiles—lowering triglycerides, increasing HDL cholesterol, and potentially increasing larger, less harmful LDL particles—the diet can reduce the risk of atherosclerosis, a major contributor to heart disease. Additionally, the diet’s anti-inflammatory effects can help reduce chronic inflammation, a key factor in the development and progression of cardiovascular disease.

Diabetes

The ketogenic diet helps manage and potentially reverse type 2 diabetes by reducing carbohydrate intake, which lowers blood glucose levels and improves insulin sensitivity. This stabilization of blood sugar reduces the need for insulin and diabetes medications, while also lowering HbA1c levels, indicating better long-term blood sugar control.

Cancer

The ketogenic diet’s potential benefits for cancer are linked to its ability to lower blood glucose levels and insulin, depriving cancer cells of their primary fuel source. Cancer cells typically rely heavily on glucose for energy, and by reducing glucose availability, the ketogenic diet may slow tumor growth and proliferation. Moreover, the diet has been shown to enhance the effectiveness of traditional cancer treatments like chemotherapy and radiation therapy by making cancer cells more susceptible to these treatments while protecting normal cells. 

Alzheimer’s disease

Emerging research suggests that the ketogenic diet may improve cognitive function and slow the progression of Alzheimer’s disease. The diet’s high-fat, low-carb regimen helps reduce neuroinflammation and oxidative stress, which are key factors in Alzheimer’s. Enhanced mitochondrial function due to ketosis provides a more efficient energy supply to brain cells, potentially improving memory and cognitive abilities in Alzheimer’s patients.

Hyperlipidemia

Hyperlipidemia, characterized by high levels of lipids in the blood, is a significant risk factor for cardiovascular disease. The ketogenic diet can positively impact lipid profiles by lowering triglycerides and increasing high-density lipoprotein (HDL) cholesterol, often referred to as “good” cholesterol. Although some concerns exist about the diet’s potential to raise low-density lipoprotein (LDL) cholesterol, many studies suggest that the increase primarily affects larger, less harmful LDL particles. 

While the ketogenic diet can offer significant health benefits, it is important to be aware of its potential risks. 

Short-term risks

  1. Flu-like symptoms (“Keto Flu”): The body undergoes a significant metabolic shift when transitioning from burning carbohydrates to fats, leading to flu-like symptoms such as fatigue, headache, dizziness, nausea, and irritability. These symptoms, often referred to as “keto flu,” typically last for a few days to a week. 
  2. Nutrient deficiencies: The restrictive nature of the ketogenic diet can lead to insufficient intake of essential vitamins and minerals, including vitamins A, C, K, and folate, as well as minerals like magnesium, potassium, and calcium.
  3. Electrolyte imbalance: The ketogenic diet promotes diuresis, leading to increased urine production and potential loss of electrolytes such as sodium, potassium, and magnesium. This imbalance can cause symptoms like muscle cramps, fatigue, and dizziness. 
  4. Digestive issues: The ketogenic diet can lead to digestive problems, such as constipation or diarrhea, due to changes in dietary fiber intake. This often results from reducing high-fiber fruits, vegetables, and grains.
  5. Ketoacidosis: Although rare, ketoacidosis is a serious condition where the body produces dangerously high levels of ketones, leading to acidic blood. This is more common in individuals with type 1 diabetes. 

Risks for specific conditions

  1. Heart disease: While the ketogenic diet can improve some cardiovascular markers, it may initially increase LDL cholesterol levels in some individuals, which could pose a risk for heart disease.
  2. Liver disease: Since the liver processes fats, a high-fat ketogenic diet can strain liver function, especially in individuals with pre-existing liver conditions. 
  3. Diabetes: The ketogenic diet can significantly affect blood sugar levels and insulin requirements, posing a risk of hypoglycemia (low blood sugar) if medications are not adjusted accordingly, especially for individuals with type 1 diabetes. 
  4. Kidney stones: The ketogenic diet increases the risk of kidney stones due to higher levels of ketones and potential dehydration, which can increase calcium excretion in the urine. 
  5. Pregnancy: The ketogenic diet is generally not recommended during pregnancy due to potential risks for both the mother and the developing baby. Nutritional needs are higher during pregnancy, and the restrictive nature of the diet may lead to deficiencies. 
  6. Bone health: This risk is primarily due to changes in calcium and vitamin D levels, which are crucial for maintaining strong bones. The diet’s restrictive nature can limit the intake of foods rich in these nutrients, and the increased excretion of calcium in urine, a common side effect of ketosis, can further exacerbate this issue.
  7. Menstrual irregularities: The ketogenic diet can cause significant changes in a woman’s hormonal balances. The reduction in carbohydrate intake can influence insulin levels and lead to alterations in the production of reproductive hormones like estrogen and progesterone. These hormonal changes can result in irregular menstrual cycles, amenorrhea (absence of menstruation), or changes in menstrual flow and duration.

Solutions and preventions

  1. Gradual transition: Transitioning to a ketogenic diet gradually, rather than abruptly, can help the body adjust more comfortably to the significant changes in macronutrient intake. By slowly reducing carbohydrate consumption and incrementally increasing fat intake over a period of weeks, the body can adapt to the new energy source (ketones) without experiencing severe “keto flu” symptoms. 
  2. Balanced nutrition: Ensuring a well-rounded intake of nutrients is crucial for maintaining overall health while on the ketogenic diet. The restrictive nature of the diet can lead to nutrient deficiencies if not carefully managed. To prevent this, it is important to include a variety of nutrient-dense, low-carb foods in the diet, such as leafy greens, nuts, seeds, fatty fish, and avocados. These foods provide essential vitamins and minerals like magnesium, potassium, calcium, and vitamins A, C, and K.
  3. Medical supervision: Regular monitoring by healthcare professionals is essential for individuals on the ketogenic diet, especially those with existing health conditions. Medical supervision helps ensure that the diet is tailored to meet individual health needs and that any necessary adjustments to medications or health markers are made promptly. Regular check-ups allow for monitoring of blood glucose levels, lipid profiles, liver and kidney function, and nutrient levels. 
  4. Lifestyle integration: Incorporating the ketogenic diet into a sustainable lifestyle is key to long-term success. This involves adapting the diet to fit individual health needs, preferences, and daily routines. Planning and preparing meals ahead of time can help maintain consistency and avoid the temptation of high-carb foods. Finding suitable keto-friendly alternatives for favorite foods can make the diet more enjoyable and easier to stick with. 
  5. Hydration and electrolytes: Proper hydration and electrolyte balance are critical when following a ketogenic diet. The diet’s diuretic effect increases urine production, which can lead to dehydration and the loss of essential electrolytes such as sodium, potassium, and magnesium. To mitigate this risk, it is essential to drink plenty of water throughout the day. Including electrolyte-rich foods in the diet, such as avocados, nuts, seeds, and leafy greens, can help maintain electrolyte balance. 

  1. Masood W, Annamaraju P, Khan Suheb MZ, et al. Ketogenic Diet. [Updated 2023 Jun 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499830/
  2. Garner S, Davies E, Barkus E, Kraeuter AK. Ketogenic diet has a positive association with mental and emotional well-being in the general population. Nutrition. 2024;124:112420. doi:10.1016/j.nut.2024.112420 Available from: https://www.sciencedirect.com/science/article/pii/S0899900724000704
  3. Masood W, Annamaraju P, Khan Suheb MZ, Uppaluri KR. Ketogenic Diet. In: StatPearls. Treasure Island (FL): StatPearls Publishing; June 16, 2023.Available from: https://pubmed.ncbi.nlm.nih.gov/38669832/
  4. Danan A, Westman EC, Saslow LR, Ede G. The Ketogenic Diet for Refractory Mental Illness: A Retrospective Analysis of 31 Inpatients. Front Psychiatry. 2022;13:951376. Published 2022 Jul 6. doi:10.3389/fpsyt.2022.951376 Available from: https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2022.951376/full
  5. Zhou C, Wang M, Liang J, He G, Chen N. Ketogenic Diet Benefits to Weight Loss, Glycemic Control, and Lipid Profiles in Overweight Patients with Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trails. Int J Environ Res Public Health. 2022;19(16):10429. Published 2022 Aug 22. doi:10.3390/ijerph191610429 Available from:  https://pubmed.ncbi.nlm.nih.gov/36012064/
  6. Dietch DM, Kerr-Gaffney J, Hockey M, et al. Efficacy of low carbohydrate and ketogenic diets in treating mood and anxiety disorders: systematic review and implications for clinical practice. BJPsych Open. 2023;9(3):e70. Published 2023 Apr 17. doi:10.1192/bjo.2023.36 Available from:  https://pubmed.ncbi.nlm.nih.gov/37066662/
  7. D’Andrea Meira I, Romão TT, Pires do Prado HJ, Krüger LT, Pires MEP, da Conceição PO. Ketogenic Diet and Epilepsy: What We Know So Far. Front Neurosci. 2019;13:5. Published 2019 Jan 29. doi:10.3389/fnins.2019.00005 Available from:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6361831/
  8. Garner S, Davies E, Barkus E, Kraeuter AK. Ketogenic diet has a positive association with mental and emotional well-being in the general population. Nutrition. 2024;124:112420. doi:10.1016/j.nut.2024.112420Available from:  https://www.jmir.org/2017/2/e36/
  9. Saslow LR, Mason AE, Kim S, et al. An Online Intervention Comparing a Very Low-Carbohydrate Ketogenic Diet and Lifestyle Recommendations Versus a Plate Method Diet in Overweight Individuals With Type 2 Diabetes: A Randomized Controlled Trial. J Med Internet Res. 2017;19(2):e36. Published 2017 Feb 13. doi:10.2196/jmir.5806 Available from:  https://pubmed.ncbi.nlm.nih.gov/29763005/
  10. 7+ Potential Risks & Dangers of The Keto Diet Available at:  https://www.ruled.me/ketogenic-diet-risks/