Is ketosis necessary for weight loss?

Ketosis involves a high level of chemicals called ketones in the body. Ketone levels become elevated when glycogen stores in the liver have run out and the body needs to burn stored fat for energy. Ketosis can be caused by a diet low in carbs and high in protein.

Some people believe that very high-protein diets are the best way to lose weight. The reality is that these diets only enhance the initial water loss that is commonly seen at the beginning of a weight-loss program. Over time, very high-protein diets do not lead to a superior weight loss. Also, the large amount of protein consumed on this type of diet places excessive stress on the kidneys. Very high-protein diets can also make you feel tired, light-headed, and irritable.

Weight Watchers encourages moderate amounts of  lean protein as part of healthful weight loss.

Weight Watchers offers a comprehensive approach to weight loss that can help you reach your goals.
Wendy Batts
Ketosis is not a usual state for the body to be in. It is a back up state when the body (the brain in particular) can no longer rely on its main energy source, glucose, sugar's most basic form.
It is not necessary or recommended for weight loss. Energy levels will be drastically reduced and your ability to sustain and recover from any activity will be compromised. Weight loss is about burning more calories than you consume in a healthful manner. Incorporation of increased activity with cardiorespiratory exercise and resistance training along with a sensible reduced calorie diet is the way to go!
Dominique Adair

Ketosis is not necessary for weight loss.  Promoted by some low/no carb diets, ketosis is actually an indication that energy metabolism is not working as well as it could.  Here's a little science...ketosis is characterized by elevated levels of ketene bodies in the blood.  Ketene bodies are formed when the liver glycogen (the body's storage form of carbohydrate) stores are depleted.  We actually need some of this carbohydrate to completely metabolize fat -- so from a health and weight loss perspective it doesn't make much sense.

Why then are these low/no carb diets so popular, and apparently successful in some people?  If you take out ice cream, cookies, chips, crackers, muffins, cake, doughnuts, coffee cake, and pastry from your diet, what do you think will happen?  Yes! You will lose weight.  But you can also lose weight by limiting those things and still eating health promoting and appetite satiating things like brown rice, sweet potato, whole wheat pasta, high-fiber cereals and bread.  But as with anything else you need to be conscious about portions.  Ketosis no.  Portion awareness yes.

Michael T. Murray, ND
Naturopathic Medicine

Absolutely not, and while ketosis is usually not dangerous (though it can be life-threatening if severe, especially in a diabetic), it is certainly not a particularly healthful state. In addition, one of the major problems with a low-carb diet or even a very low-calorie diet is that they inevitably produce a loss of significant amounts of muscle mass. The muscle is sacrificed in order to provide the dieter with a constant supply of blood sugar. In fact, if you lose weight through fasting or other forms of severe dieting, a significant proportion of the weight loss will be in the form of water (each molecule of glycogen binds six water molecules) and muscle mass. This sort of weight loss will significantly lower your metabolic rate and reduce the primary fat-burning furnace in the body, lean muscle mass, thereby setting you up for serious weight gain later on.

Hunger Free Forever: The New Science of Appetite Control

More About this Book

Hunger Free Forever: The New Science of Appetite Control

From two leading authorities on appetite control, obesity, natural medicine, and food comes a breakthrough in getting healthy and staying slim without starving.Millions have spent years searching for...

Continue Learning about Weight Loss

You've Got the Beat
You've Got the Beat
Here's another reason to stick with your New Year's weight loss efforts. Maintaining a healthy weight could help ward off dangerous heart arrhythmias....
Read More
How do fat absorbing diet pills work to help me lose weight?
Gretchen M. Bosacker, MDGretchen M. Bosacker, MD
Fat absorbing diet pills use a fiber mechanism to bind fat after you've eaten it, so fat passes thro...
More Answers
How to Find the Perfect Health Buddy
How to Find the Perfect Health BuddyHow to Find the Perfect Health BuddyHow to Find the Perfect Health BuddyHow to Find the Perfect Health Buddy
Get tips from Dr. Mike Roizen’s latest book, This is YOUR Do-Over.
Start Slideshow
Lose Weight With Your Smartphone
Lose Weight With Your Smartphone

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.