“Ketogenic” is a term for a low-carb diet (like the Atkins diet). The idea is for you to get more calories from protein and fat and less from carbohydrates. You cut back most on the carbs that are easy to digest, like sugar, soda, pastries, and white bread.
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.
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.
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.
You want to keep your carbohydrates limited, coming mostly from vegetables, nuts, and dairy. Don’t eat any refined carbohydrates such as wheat (bread, pasta, cereals), starch (potatoes, beans, legumes) or fruit. The small exceptions to this are avocado, star fruit, and berries which can be consumed in moderation.
Do Not Eat
- Grains – wheat, corn, rice, cereal, etc.
- Sugar – honey, agave, maple syrup, etc.
- Fruit – apples, bananas, oranges, etc.
- Tubers – potato, yams, etc.
- Meats – fish, beef, lamb, poultry, eggs, etc.
- Leafy Greens – spinach, kale, etc.
- Above ground vegetables – broccoli, cauliflower, etc.
- High Fat Dairy – hard cheeses, high fat cream, butter, etc.
- Nuts and seeds – macadamias, walnuts, sunflower seeds, etc.
- Avocado and berries – raspberries, blackberries, and other low glycemic impact berries
- Sweeteners – stevia, erythritol, monk fruit, and other low-carb sweeteners
- Other fats – coconut oil, high-fat salad dressing, saturated fats, etc.
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
- 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.
The information in this article mostly applies to the standard ketogenic diet (SKD), although many of the same principles also apply to the other versions.