A keto diet is well known for being a low carb diet, where the body produces ketones in the liver to be used as energy. It’s referred to as many different names – ketogenic diet, low carb diet, low carb high fat (LCHF), etc.
A ketogenic diet plan improves your health through a metabolic switch in the primary cellular fuel source to which your body and brain are adapted. When your metabolism switches from relying on carbohydrate-based fuels (glucose from starch and sugar) to fat-based fuels and fat metabolism products called ketones, positive changes in the health of your cells occur, and this translates into better overall health.
A metabolic process called ketogenesis and a body state called ketosis are responsible. Ketosis is simply a normal metabolic pathway in which body and brain cells utilize ketones to make energy, instead of relying on only sugar (i.e., carbohydrate). In fact, humans developed an evolutionary ability to burn ketones as an adaptation to periods of time when food was unavailable, and being in nutritional ketosis is a beneficial body state.
A great deal of research is being done on ketosis as it relates to disease. Ketone bodies have some very beneficial effects on the human body, and elevating one's blood levels of ketone bodies is an effective treatment for many disease conditions because it improves the function of cellular energy pathways and mitochondrial health. Ketogenic diets are now being used to treat medical conditions such as diabetes, epilepsy, autism, Alzheimer's, cancer and others and much of the success of these treatments is rooted in these cellular effects.
Note of Caution
You should check with your physician if you have any concerns about starting a ketogenic diet plan with pre-existing health conditions, especially if those conditions involve kidney or heart problems. People with kidney disease should definitely consult with their physician about starting a ketogenic diet.
When you eat something high in carbs, your body will produce glucose and insulin.
- Glucose is the easiest molecule for your body to convert and use as energy so that it will be chosen over any other energy source.
- Insulin is produced to process the glucose in your bloodstream by taking it around the body.
FAT VS CARBORHYDRATES
Since the glucose is being used as a primary energy, your fats are not needed and are therefore stored. Typically on a normal, higher carbohydrate diet, the body will use glucose as the main form of energy. By lowering the intake of carbs, the body is induced into a state known as ketosis.
Ketosis is a natural process the body initiates to help us survive when food intake is low. During this state, we produce ketones, which are produced from the breakdown of fats in the liver.
The end goal of a properly maintained keto diet is to force your body into this metabolic state. We don’t do this through starvation of calories but starvation of carbohydrates.
Our bodies are incredibly adaptive to what you put into it – when you overload it with fats and take away carbohydrates, it will begin to burn ketones as the primary energy source. Optimal ketone levels offer many health, weight loss, physical and mental performance benefits.
Different Types of Ketogenic Diets
There are several versions of the ketogenic diet, including:
- Standard ketogenic diet (SKD): This is a very low-carb, moderate-protein and high-fat diet. It typically contains 75% fat, 20% protein and only 5% carbs (1).
- Cyclical ketogenic diet (CKD): This diet involves periods of higher-carb refeeds, such as 5 ketogenic days followed by 2 high-carb days.
- Targeted ketogenic diet (TKD): This diet allows you to add carbs around workouts.
- High-protein ketogenic diet: This is similar to a standard ketogenic diet, but includes more protein. The ratio is often 60% fat, 35% protein and 5% carbs.
However, only the standard and high-protein ketogenic diets have been studied extensively. Cyclical or targeted ketogenic diets are more advanced methods, and primarily used by bodybuilders or athletes.
Other Health Benefits of the Ketogenic Diet
The ketogenic diet actually originated as a tool for treating neurological diseases, such as epilepsy.
Studies have now shown that the diet can have benefits for a wide variety of different health conditions:
- Heart disease: The ketogenic diet can improve risk factors like body fat, HDL levels, blood pressure and blood sugar (32, 33).
- Cancer: The diet is currently being used to treat several types of cancer and slow tumor growth (4, 34, 35, 36).
- Alzheimer's disease: The diet may reduce symptoms of Alzheimer's and slow down the disease's progression (5, 37, 38).
- Epilepsy: Research has shown that the ketogenic diet can cause massive reductions in seizures in epileptic children (3).
- Parkinson's disease: One study found that the diet helped improve symptoms of Parkinson's disease (39).
- Polycystic ovary syndrome: The ketogenic diet can help reduce insulin levels, which may play a key role in polycystic ovary syndrome (40).
- Brain injuries: One animal study found that the diet can reduce concussions and aid recovery after brain injury (41).
- Acne: Lower insulin levels and eating less sugar or processed foods may help improve acne (42).
However, keep in mind that research into many of these areas is far from conclusive.