Weight Loss

Exactly How Ketosis Helps Weight Loss

By Kim Crawford, M.D. Last updated: October 19, 2017
how ketosis help weight loss

The Nutritional Ketosis Diet Plan

Are you tired of going from one weight loss plan to another? Most of my patients and AWS clients who want to lose weight are not at their “first rodeo.” A weight loss plan that will work is a plan you can either stay on or segue to on and off through life. Have you wondered “does ketosis work for weight loss or is it just a fad?” Have you read the naysayer articles from dieticians who argue you will be deprived of nutrients and fiber? Do you almost believe the stories of successful and lasting weight loss but wonder exactly how ketosis helps weight loss?

If you follow the right type of ketotic diet (eating healthfully; not a processed-food-laden Atkin’s diet), you’ll lose weight. Current data shows you are more likely to keep it off if you can “keto-adapt” during nutritional ketosis throughout life. A nutritional ketosis diet (standard ketogenic diet) will not only help you achieve an ideal weight (1), but it might even be somewhat anabolic; enhancing athletic performance. Let’s begin with food.

What Do I Have to Eat?

does ketosis work for weight loss with this kind of food?I’m laughing to myself as I write this, remembering the way my husband phrased it to me: “So, what are you taking away from me now?”

This is, I’ve come to realize, how most people view any sort of diet plan.

People think of a “diet” as a punitively restrictive way they must force themselves to eat so they can lose weight. It further implies they can go back to eating “the same old way” when they have lost the weight.

What I’d like to propose to you about a “keto lifestyle” is that you can lose your weight easily by becoming what is called “keto-adapted.” This simply means you have re-trained your metabolism to use fat for fuel and to do it readily or on demand.

You can then follow a healthy (meaning good for your health) anti-inflammatory diet, Paleo plan, or even the Keto diet for life. To be healthy, trim and fit, you cannot eat the junk you ate when you were in your teens and early 20’s. Come to terms with this so you can be the fittest, most attractive, healthiest version of yourself. Don’t be discouraged, though! You will love the high-fat dishes you can prepare on the keto plan. You will not have cravings. You’ll feel great. I daresay you will grow not to miss your donut-burgers too.

The eating guidelines for this “keto diet plan” are as follows. You want to consume 70-80% healthy fats, 10-20% protein and only 5% carbohydrates. This does contradict the last 20+ years of dietary recommendations of low-fat, high-carb eating for weight loss and health. However, it’s precisely the high-carb, low-fat eating that has caused the epidemic of obesity, diabetes, heart disease and increases in cancer all over the world. Next, let’s discuss the benefits of losing weight with “keto.” The majority of people on weight loss diets, when surveyed, complain that cravings trip them up over 95% of the time. Guess what? That will be taken out of the equation.

Cravings in Keto

When you’re eating a standard American diet laden with starches and sugars, a normal blood sugar level is rare. Instead, your hunger (in general) and your cravings (in particular) are responding to the wild fluctuations as your body copes to burn varying amounts of glucose (sugar). When you burn a cleaner “higher octane” fuel, fat, your blood sugar becomes stabilized. This stabilization will tamp down carb and sugar cravings. You can consume enough building blocks for the calming neurotransmitter serotonin with fish, red meat, and poultry as well as certain organic seeds. So, the lack of starch shouldn’t cause serotonin deficiency issues unless you’re already somewhat deficient. I’ll review keto foods (especially the types of healthy fats) which help nuke your cravings when I discuss satiety matters below.

Metabolism in Keto

Are you sick of counting calories? Once you go “keto,” you won’t have too. While you are adapting and getting to know the amount of fat, carbs, and protein in food X, Y or Z, you’ll only need to roughly track (unless you’re a spreadsheet kind of person which I’m not). In the bizarro-world of eating lots of fat—more fat than you ever dreamed you’d be eating—you’re also asked not to snack. Of course, this is “bizarro” since, in the high-carb days, you were told to snack, snack, snack to keep your blood sugar stable. That’s not necessary, and you won’t even want to.

Eat until you are full and try not to snack. Ketosis is a natural metabolic booster, so don’t fear the “fat calories.” Your body will convert healthy fat to heart and brain-healthy ketones and use them for fuel, with the excess being excreted in your urine and through your lungs. Just being in a “good ketosis” will make you burn more calories. On average, men burn an extra 450 kcals per day (2) while women burn an extra 150 kcals/day. The benefits are not just an increase of metabolism, though. Since the ketones are a “cleaner burning fuel,” they leave less free radical waste products than when your body burns glucose. As a result, your general state of oxidative stress will improve. However, that’s not all that the ketones do. Here’s why I think this eating plan is so magical.


Ketosis will Suppress Hunger Pangs

The standard (high-carb) American diet (S.A.D.) causes blood sugar swings that can cause cravings as well as hunger pangs; sometimes within just two hours of eating a big meal. When you’re in ketosis, and burning fat for fuel, your blood sugar will stabilize at a lower and healthier level. In addition, fat is wonderful for satiety. Ketosis is a wonderful appetite suppressant. The healthy fat you ingest is metabolized into ketones by your liver, and they suppress your hunger (for hours) via several metabolic pathways.

Leptin and Ghrelin AKA the Hunger Hormones

When it comes to most hunger pangs, the culprit is ghrelin; not leptin. Ghrelin is the principal hunger hormone which increases appetite. When you eat something, ghrelin levels drop, but not as much as they actually should drop if you are over your ideal body weight. It’s worse if you undertake a weight loss mission using a non-ketotic diet. To explain, your body senses that you are “starving it” and your ghrelin levels actually increase. This is a major reason non-ketotic diets fail. If you’re on a ketotic diet, ghrelin levels do not increase as you lose weight.

Leptin is less of a hunger hormone and more of a “fat storage hormone.” Regarding hunger, leptin is more of a “stop eating” hormone. Ketosis doesn’t suppress leptin when you first start this diet. That fact doesn’t appear to be an issue concerning hunger, weight loss or fat loss in the early stages of this plan. Leptin resistance is improved the more you stay in ketosis and incorporate prolonged periods of not eating (intermittent fasting) into your ketosis plan.

A general rule of thumb to optimize weight loss and health benefits of eating a nutritional ketosis diet is to stop eating 3 hours before bedtime and then keep 12 hours (up to 16 hours to get an A+) as water only; until your next meal the following day. Realize I’m now instructing that it is fine to skip breakfast. It’s the bizarro-world diet, isn’t it? It is probably just fine to have A.M. coffee with fat in it and have this still “count”; studies are not conclusive but I am hoping this is metabolically not “breaking the fast.”

Other Satiety Hormones

As you just read, traditional diets lead to increased ghrelin levels, where a keto diet does not. Traditional high-carb diets also produce a reduced concentration of what are called “satiety peptides.” These peptide hormones include cholecystokinin, glucagon-like peptide-1, and peptide YY.  By the third day of reaching a steady ketosis, (3) these satiety responses will have all kicked in.

Fat, Protein and Satiety

How satisfied you feel eating a certain way will determine whether or not you have to “power through it” or “enjoy the ride.” It’s no mystery what course of action will be easier and lead to a higher rate of success. Satiety is a really important issue for weight management. The highly profitable “diet machine” in the U.S. wants to feed you “diet foods” or worse, tell you that you can lose weight while eating pizza and chips. No matter whether you choose to “go keto” or not, I hope you’re aware so-called “diet foods” are not only seriously unhealthy, but promote weight gain (not weight loss) through glycation, and inflammation. Diet foods contain a mountain of chemical additives; while sweeteners such as aspartame are even documented as appetite stimulants. These foods are also high-carb and contribute to why two-thirds of us are overweight.

how ketosis helps weight loss using avocadosTo “eat for maximal satiety,” eat healthy fats; something conventional diets don’t allow you to do. Healthy fats such as olive oil, coconut oil, grass-fed butter, MCT oil, avocado oil and ghee slow down the absorption of everything else you are eating to add to the ketosis “anorexic effect.”

When you’re planning the food composition of your meals, protein is what tells your satiety center that you are full before carbohydrates and even fats.

You might accidentally eat a higher protein content than “allowed” to remain in ketosis to try to feel fuller quicker; let’s review this somewhat controversial topic.

For years, nutritionists egged on by athletic coaches and participants have recommended that we eat a gram of protein per pound of bodyweight—with athletes being told to eat 1.5 or even 2 grams per pound of bodyweight per day. That is just excessive when we’re talking keto needs even for elite and very knowledgeable athletes such as Mark Sisson. 

There is a currently accepted range of what’s necessary for protein intake. Excess protein will put ketosis to a dead halt, so you need to watch your consumption. For example, nuts are an “allowed snack,” but too many handfuls will knock you out of ketosis. A scientific way to calculate your protein needs is to measure your body fat (or find an online calculator) and figure out how many pounds of lean body mass you have. Some sources will have you eating .7-1 gram of protein per pound of lean body mass (elite athletes need 1 gram). Other sources will take your lean body mass in pounds divided by 2.2 to get your lean mass in kilograms. To follow, you then consume as little as .7 grams of protein per kilo of lean body mass, with an extra allowance for athletes.

For those of you who are used to your post-workout carb re-feed, you’ll deplete your glycogen stores and enhance ketosis during an intense workout, and you might crave carbs if this happens. Take it easy at first. Do regular “cardio” versus your HIIT training and you’ll get used to keto re-feeding. (It will feel great!) For me, this part was hard at first. Have some hard boiled eggs ready if you feel a crash coming during a workout.


People have asked me about the “keto flu”. Brain fog and sleep disturbance (if any) clear up after the first two weeks. Other than that, here are a couple of little warnings. Type 1 diabetics should not undertake this diet without careful monitoring by their doctor, if at all. Those with inflammatory bowel disorder or leaky gut should know ketone bodies have been shown to alter gut mucosa. That doesn’t mean you shouldn’t use this diet plan. It just means to be aware. In fact, some studies show beta-hydroxybutyrate and butyric acid (ketones) are good for the gut. At the moment, we’re not 100% certain so I ask my dieters (after the first 6 weeks of keto-adaptation) to break ketosis every other week with a starchy carb (sweet potatoes) dinner.


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