Ketosis is often associated with the initial phase of low-carbohydrate diets, a practice popularized when the "Atkins Diet" was published in 1972. Although ketosis may include some side effects, many people point to their rapid weight loss as a reason to try it. However, induction periods and ketosis are typically designed to only be used short-term, and you should check with your doctor before starting any ketosis-based weight loss program.
Ordinarily, your body uses glucose, a type of sugar, as its primary energy source. When you don't consume enough glucose-containing foods like carbohydrates, your body uses fat for energy instead. As fats are broken down for energy, chemicals called ketones are released into your blood and urine, putting you in what is known as a state of ketosis. Ketosis usually occurs when your carbohydrate intake dips below 20 g per day.
Examples of low-carbohydrate diets include Atkins, Zone, Protein Power, Sugar Busters and Stillman. Not all of them emphasize a ketosis state, although if you eat less than 20 g of carbohydrates per day on any low-carb diet, ketosis will occur. Most of the low-carb plans use phases where you spend two to four weeks with very low carb consumption, then gradually include more carbs and types of foods in subsequent phases. A study in the "American Journal of Clinical Nutrition" in 2008 found that in the short term, ketogenic diets that are high in protein and low in carbohydrates will reduce hunger and lower your food intake much better than nonketogenic diets that are high in protein and allow medium levels of carbohydrates.
Induction is simply a term for an initiation or initial period. The induction phrase of any ketogenic diet such as Atkins requires you to eat 4 to 6 oz. of protein foods with each meal and a variety of non-starchy vegetables. You are also allowed 4 oz. of cheese daily and fats such as butter and margarine, as well as zero-calorie beverages and artificial sweeteners. You are not allowed any sugars, starches, grains or fruits, except for a small amount of lemon and lime juice.
In order to verify your body is in a state of ketosis, you can buy test strips at a drug store that can detect ketones in your saliva. Ketosis also affects your breath, making it smell sweet and fruity. The short-term term weight loss from ketosis may be caused by dehydration, and in many cases dieters regain all their lost weight when they return to a normal carbohydrate intake.
Some people experience weakness, nausea, dehydration, dizziness and irritability during ketosis, according to MayoClinic.com, which also warns that excess saturated fat and cholesterol can increase your risk of heart disease and possibly certain cancers. If you are diabetic, avoid any form of ketosis, since a lack of insulin can make you experience something called ketoacidosis, a life-threatening condition. The nutrition committee of the American Heart Association issued a science advisory warning that high-protein diets have not been proven effective and pose health risks.
- Medical News Today; What Is Ketosis? What Causes Ketosis?; Christian Nordqvist
- Atkins.com: Phase 1, Induction
- Quackwatch; Low-Carbohydrate Diets; Stephen Barrett, M.D.
- "The American Journal of Clinical Nutrition"; Effects of a High-Protein Ketogenic Diet on Hunger, Appetite, and Weight Loss in Obese Men Feeding Ad Libitum; Alexandra M Johnstone, et al.; 2008
- MayoClinic.com; Low Carb Diet; May 2010