There is a significant amount of glucose in the average diet, which the body uses for energy. When a body goes into ketosis, this means there is not enough glucose available to meet energy needs, so the body must metabolize fat for energy, in turn creating molecules known as ketones. This process should not be confused with ketoacidosis, which is a potentially life-threatening condition associated with Type 1 diabetes. Ketoacidosis occurs when ketone levels are higher than the diet allows.
Since ketosis is a necessary component of a ketogenic diet, not all low or reduced carbohydrate diets are ketogenic. The exact amount of carbohydrates that can be consumed while still maintaining ketosis varies depending on the individual metabolism and activity level. In general, most people can eat 50 to 60 grams of net carbohydrates and maintain ketosis. More active people can generally eat more carbohydrates, while those with sedentary lifestyles and lower metabolisms may need to consume smaller amounts.
The most recommended foods for ketogenic diets are typically fatty foods, which includes fish and fish oils, butter, avocado, egg yolks, sausage, poultry and vegetables grown above ground. Heavy dairy products and an assortment of nut varieties also fit into a ketogenic diet.
The main goal of a ketogenic diet is to build the blood level up to a state of metabolic ketosis, which refers to a state in which the level of ketone in the body is elevated and breaks down body fat to create energy and boost the metabolic process. Therefore, foods that are high in saturated fats and low in carbohydrates are recommended for the diet, which also minimizes insulin levels in the body.
Wild salmon and shellfish are among the recommended choices for fishes and oils, and those who have fish allergies or prefer not to eat it may take fish oil or krill oil supplements. People on ketogenic diets should avoid foods with hydrogenated fats, such as margarine, because trans fat intake needs to be minimized. If cooking with oils, coconut oil and olive oil are good choices.
Meats and proteins are a significant part of the ketogenic diet, and fresh, unprocessed, organic or grass-fed meats are the most recommended. Meats from grass-fed animals generally boast higher fatty acid counts. Natural peanut butter can be a good source of protein, but may contain carbohydrates, so macadamia nut butter is a better choice.
For vegetables, dark and leafy choices, such as spinach, contain low levels of carbohydrates and are rich in nutrients. Hard or soft cheeses are good for dairy intake, along with cottage cheese. Small amounts of low-carb nuts, such as walnuts, almonds and macadamias fit into the diet, as well. Large quantities of beverages, such as water, tea or coffee, round out the diet.