Keto Clarity: Your Definitive Guide to the Benefits of a Low-Carb, High-Fat Diet (41 page)

In many clinical studies, the spontaneous reduction in calorie intake experienced by low-carbohydrate dieters is similar in magnitude to that experienced by people advised to restrict calories by cutting down on dietary fat. One study compared two different low-carbohydrate diets, one with higher protein and another with higher fat, to a calorie-restricted, low-fat diet. The results showed that the spontaneous reduction in calorie intake in the two low-carbohydrate diets was modestly greater than what the low-fat dieters were able to accomplish and provided more weight and body-fat loss. Another study found the spontaneous calorie intake reduction in those assigned to a low-carbohydrate diet didn’t surpass that of those instructed to reduce calorie intake by reducing fat intake. And yet those assigned to the low-carb group lost over twice as much body fat.

– Dr. Bill Lagakos

This one has always been especially amusing to me. The argument goes a little something like this: the only reason people succeed on a ketogenic diet is that their appetites are suppressed to the point that they don’t eat as many calories as they otherwise would. Does anyone else notice the irony in this? While ketogenic opponents think this is a “gotcha” moment, it actually strengthens the case for ketosis even more. Pharmaceutical companies have spent hundreds of millions of dollars attempting to create effective drugs for reducing appetite levels. And yet here we have a natural way to do just that, without any risky side effects.

There’s a huge difference between counting calories without regard to the
quality
of those calories and being mindful in selecting the kind of foods that will fill you up and satisfy you. The fact is, calories are naturally managed on a ketogenic diet when you eat to satiety because your hunger is completely controlled; you never have to pull out your calculator to make sure you’ve stayed within some arbitrary calorie goal. Have you ever wondered how animals in the wild stay so lean and healthy without counting their calories? This is a question we humans should be asking ourselves.

The idea that the kind of calories you eat matters immensely is something Temple University School of Medicine researcher Dr. Guenther Boden observed in a study published in the March 15, 2005, issue of
Annals of Internal Medicine
. Dr. Boden concluded that “excessive overeating had been fueled by carbohydrates.” Carbohydrates increase insulin levels, which leads to the desire to eat more and more calories. But ketogenic dieters make fat and protein their primary food intake, and hunger is well under control. This doesn’t occur by accident.

When most people begin a ketogenic diet, eating becomes just a normal response to appetite, sometimes for the first time in their lives. I’d say that makes ketosis very special and desirable for anyone who wants to be free from the bondage of calorie-counting forever.

DOCTOR’S NOTE FROM DR. ERIC WESTMAN: Eating carbohydrates makes you hungry. If you don’t eat carbohydrates, there is no hunger. Of course, you’ll never know this until you stop eating carbohydrates. Most Americans have eaten carbohydrates every single day of their lives!

2. Weight loss during ketosis comes mostly from a loss of water weight and the breakdown of organs and muscle.

It’s always humorous to hear people criticize the weight loss that happens during ketosis by mockingly stating that “it’s only water weight.” But the fact is, when we start to lose weight through
any
method, it’s mostly water weight we lose at first. This is partly due to the release of glycogen stores in the muscles. Glycogen, the stored sugar in the body, is filled with water. And since low-carb diets shift the body from sugar-burner to fat-burner, when glycogen is used up, it isn’t completely replaced, and when the glycogen weight is lost, water weight is also lost.

It’s also partly due to lowered insulin levels. Insulin signals the kidneys to hold on to water and salt, so when you are eating carbohydrates and generating more insulin, you are also retaining more water and salt. Reducing carbohydrate consumption lowers insulin levels, resulting in less retention of salt and water. These certainly aren’t bad things, and they explain why some people who are overweight or obese lose a lot of weight when they first begin a low-carb, high-fat, ketogenic diet.

But the interesting aspect of ketosis is that once the water weight is lost, bona fide fat loss begins in earnest. Yes, the amount of weight lost is significantly lower at this point. However, your body is using stored body fat as fuel and is happily burning ketones. So the notion of breaking down organs and muscles on a ketogenic diet is pretty ridiculous, especially when you look at the published research.

Nutrition researcher Anssi Manninen from the University of Kuopio Medical School in Finland published a study in the January 2006 issue of the journal
Nutrition & Metabolism
that examined the effects of a very low-carb diet (defined as 10 grams of carbs per day) on muscle mass. He concluded that the ketones produced by the liver act as a restraining influence on the breakdown of muscle protein. Additionally, the presence of fatty acids and ketones can actually suppress the oxidation of the amino acids that can cause damage to muscles. In other words, rather than seeing muscle wasting on a very low-carb, ketogenic diet, Manninen says this way of eating is actually
protective
of your lean muscle mass.

DOCTOR’S NOTE FROM DR. ERIC WESTMAN: There is a brainstorming technique in which you “turn everything upside down” in order to see things differently, and often new solutions to problems will emerge. Muscle cells have glucose receptors (gateways) that require insulin to open. We typically think of these receptors as allowing glucose in, but what if we think of them keeping glucose
out
? With that shift in perspective, we can think of muscle cells as fat-burning cells that only need sugar when faced with sprinting or other activity that requires bursts of energy.

3. Very low-carb, ketogenic diets induce hypothyroidism and adrenal fatigue.

Is someone suffering from hypothyroidism because of ketosis, or is it caused by chronic low-calorie intake, stress, or something else—or even a combination of all of this? Without isolating variables, it cannot be said for certain that ketosis is the cause.

– Dr. Zeeshan Arain

Hypothyroidism can occur when one thyroid hormone, T4, isn’t easily converted into another thyroid hormone, T3. In recent years, some prominent members of the online Paleo community have promulgated the idea that the lack of glucose on a ketogenic diet leads to a diminished capacity for T4 to be converted into T3, leading to hair loss, cold hands and feet, general malaise, and other symptoms associated with low thyroid function. It all sounds so dastardly that you might wonder why anyone would ever go on a very low-carb, ketogenic diet.

The concern about thyroid function reveals a misunderstanding both among the lay public and among doctors themselves. A lower number does not necessarily mean lower function. Often it means better function. As the body is functioning better, thyroid levels go down. This is a very desirable state. This is what distinguishes health and longevity in many instances. Centenarians have lower thyroid than their elderly peers. When people criticize a very low-carbohydrate diet by saying that it causes hypothyroidism, it’s not only misleading but overtly wrong.

– Dr. Ron Rosedale

The problem with this criticism is that it is incomplete. While some on a ketogenic diet may experience hypothyroidism if they aren’t consuming enough calories, when calories are adequate, hypothyroidism doesn’t occur. It’s the number of calories, not the ketogenic diet itself, that matters here. In research studies following people on a well-formulated low-carb, moderate-protein, high-fat diet with adequate calories, there has been no occurrence of low thyroid. And as long as the calories are not restricted on a very low-carb diet, thyroid and metabolic function remain normal, without any need for consuming additional glucose. In fact, a diminished thyroid level is not a “pathological condition,” says nutritional consultant and educator Nora Gedgaudas. As long as calories are sufficient, a lowered thyroid level is actually a sign of “improved efficiency of metabolic functioning and is literally a desirable longevity marker.”

If you happen to have thyroid issues upon embarking on a ketogenic diet, you may experience symptoms of thyroid dysfunction. But people are often very quick to confuse this association with their new diet being the cause. I have never seen the sudden development of non-preexisting thyroid disease in anyone eating a low-carb, high-fat diet. It is true that over time, there may be a slowed conversion of T4 thyroid hormone into active T3 on a well-formulated ketogenic diet. But this doesn’t mean there’s a problem.

– Nora Gedgaudas

A naturopathic physician named Dr. Chris Decker wrote on this very topic in her online article “Does Paleo Make Us Hypothyroid?”, in which she addresses exactly what happens to the thyroid when you are generating ketones while following a low-carb, moderate-protein, high-fat diet:

When we are burning ketones from fat as our primary fuel source, our thyroid just doesn’t have to work as hard as it does when it’s got to manage bodily metabolism on a less-preferred fuel (glucose). When our organs, against their better judgment, are required to metabolize sugar over fat, more T3 is needed to deal with this less-than-ideal scenario. Our thyroid has to work overtime, and somebody—poor T3!—has got to do the job. But burn fat for fuel instead, and T3 gets to stay home and put its feet up.

So a reduction in T3 levels is in fact a very
good
thing!

What we consider to be a normal level of thyroid function may actually be an elevated level due to a consistently high-carb diet, in which case the lower thyroid function observed on a low-carb, high-fat, ketogenic diet would actually be closer to a normal value.