The Fast Metabolism Diet (7 page)

The thyroid is a metabolic superstar! It is a butterfly-shaped gland located at the center of the throat, and although I know I’m mixing my metaphors here, I think of it as your body’s furnace. The pituitary gland in the brain (which will be discussed more thoroughly in the next section) is like the thermostat, and the hypothalamus in the brain is like the guy controlling the thermostat. But the thyroid is the furnace and the hormones it produces, like T3 and T4, are the heat. When it gets too hot, its thermostat
has to be turned down, and when too cold, its thermostat gets cranked up. If any of these three mechanisms isn’t working just right, then the body’s temperature—a direct reflection of metabolism, or the rate at which the body is burning energy—will be off. The house will be too hot or too cold.

The thyroid performs many metabolic tasks via many functions in the body, including the extraction of iodine from food to produce the thyroid hormones
T3 and
T4. The T3 and T4 travel through the bloodstream and influence the metabolism through the conversion of oxygen and calories to energy. This is huge! This is what you want—an efficient furnace fueled by food and heating your house so it’s toasty and comfortable. T3, in particular, is the superhero of a fast metabolism. T3 possesses approximately four times the metabolic hormone strength of T4.

But the thyroid has a dark side—a hormone called
Reverse T3 (
RT3). I introduced you to RT3 in the last chapter, but I want to bring it up again because it’s so important in the process of metabolism repair. RT3 is sort of like that dysfunctional family member who shows up at Thanksgiving but doesn’t behave and inevitably ruins everybody’s dinner. It’s a misshaped thyroid hormone that isn’t very efficient in stimulating the metabolism, and in fact, it blocks healthy T3 functioning. RT3 doesn’t mean to mess things up for you and your plans for those skinny jeans. It’s actually a smart response to prevent
starvation. The problem is, when you
diet, you know you aren’t really starving (even though on some diets it might seem that way), but your body doesn’t have the 411.

In situations when you are experiencing chronic stress, certain disease processes, or nutritional deprivation, RT3 heeds your body’s “Red Alert!” This signals the RT3 to bind to the T3 receptor sites and run interference so T3 can’t do its job. RT3 throws a big bucket of water on your metabolic fire, in a panicked effort to save your fat stores so you don’t die from what surely must be a catastrophic event or famine. The result is that your body quits burning and starts storing. Sometimes there are serious problems with the body’s thermostat, such as
Hashimoto’s disease,
Graves’ disease, or a body that is producing thyroid peroxidase (attacking its own thyroid). These thyroid-based diseases are often undiagnosed and can play a very large role in an extremely slow metabolism.

The Fast Metabolism Diet is designed to nurture and coax the right hormone production from your thyroid. But because things can go wrong
with the thyroid, I strongly believe it is important to look at the blood chemistry of the thyroid to be sure it’s functioning properly. A lot of women’s health books talk about the thyroid because
hypothyroidism is an often undiagnosed condition that can cause a slow metabolism, weight gain, hair loss, brittle nails, constipation, headaches, and fatigue. I always recommend my clients get
thyroid tested (I’ll talk about which
tests at the end of this chapter).

I briefly mentioned the pituitary in the previous section, but let’s give it some love. I think of the
pituitary gland as the body’s thermostat. It secretes hormones that regulate or adjust the actions of many other hormones in your body.

For example, the pituitary stimulates the thyroid to secrete its hormones with thyroid-stimulating hormone, or
TSH. If the TSH level is high, that means the thyroid is requiring a lot of motivation or pushing to get its job done (hypothyroid). Imagine the pituitary yelling at the thyroid:
Get going, you slacker! Move it or lose it!

If the TSH is normal, all the pituitary has to do is speak in a normal voice:
Keep up the good work.
If the TSH is very low, then the thyroid gland may be overactive
(hyperthyroid), and the pituitary may only whisper. Of course, as I’ve explained earlier, if the thyroid is producing a lot of fat-storing
RT3, the pituitary may perceive this as plenty of thyroid hormone, and may only whisper when it should be yelling. For this reason, a normal thyroid test isn’t necessarily indicative of optimal thyroid function, as it won’t separate out the RT3 from the furnace-stoking
T3.

The pituitary also regulates
sex hormone production, such as estrogen, progesterone, testosterone, and DHEA. The regulation of each of these, as well as the adrenal hormones, is crucial to the health of the body and speed of the metabolism. So the pituitary is not only the furnace’s thermostat but also the control center for the huge ecosystem called your hormones.

The final key player that directly influences the
metabolism is your
body substance—
how I refer to the
fat, bone, connective tissue, and muscle in your body. The body
stores the majority of your reserve fuel in either muscle or fat. Because muscle is constantly contracting, relaxing, beating, pushing, and pulling, it takes a lot of fuel to create and maintain it. This is why they say muscle consumes more calories, or energy, than fat. Fat just sits there. Have you ever seen it do anything besides flop over your waistband or jiggle around on your thighs? Fat really doesn’t do much but hold on to fuel, and therefore it takes very little fuel or calories to maintain it. (And remember, if you don’t eat or provide outside fuel, the body will actually break down muscle and store some of that fuel as even more fat!)

There are two basic types of fat in the body:
white fat and
brown fat. For decades scientists believed that brown fat was only present and important in infants and small children, to help keep them warm and maintain their body temperatures. It is now believed that even though it exists in very small amounts in adults, brown fat plays a crucial role in the regulation of
blood sugars and the metabolism. Brown fat is brown because it is rich in
mitochondria (remember those little parts of the cell that burn fuel and produce energy?).

The more obese you are, the less brown fat you will have and the more white fat you will have in storage (the fat you don’t like when it jiggles). This is just another sick joke on your body, because brown fat burns fuel nine times faster than white fat. So why does your body seem so in love with white fat, hoarding it like a miser? It’s because your body thought it might need the fuel reserves! (Thanks a lot, chronic dieting!) White fat’s major purpose for being is for long-term fuel, and your body will make a Herculean effort to hold on to it, just in case of disaster.

White fat isn’t all bad. In fact, you need it and it serves a very important function. White fat is the fat under your skin (subcutaneous fat) and around your organs (visceral fat). It is designed to maintain body temperature, protect the organs, and act as an energy storage site for future need. White fat also secretes some hormones and regulates the output of others, and these hormones communicate directly with the adrenals, the pituitary, and the hypothalamus.

However, when your metabolism slows down, your body goes into super white-fat production mode, hoarding fat like some people hoard newspapers, shoes, junk mail, or stray cats. You can literally be buried alive with all this saved energy in the form of smothering white fat.

Brown fat, on the other hand, is a thermogenic or furnace fat. Unlike white fat, instead of storing energy, brown fat seems to prefer to burn through it. It also helps stimulate the metabolism by warming the body, increasing blood flow, and making it easier to deliver nutrients to the white fat. Brown fat helps regulate your
cholesterol and
triglycerides, transports waste to the intestines for elimination, synthesizes
proteins, and stores and metabolizes fatty acids used for energy. Brown fat also metabolizes and stores carbohydrates,
storing them as glucose for your red blood cells and brain.

Interestingly, in adults, brown fat is typically located only behind the shoulder blades up and around the neck and under the collar bone. This is also where I and many of my clients say they feel or hold their stress. Stress hormones directly affect brown fat activity. Brown fat can be your best friend when you want to enhance your metabolism because, through its hormone activity, it releases a ton of energy from food. Brown fat also seems to be activated by cold, while the release of stored energy in white fat seems to be stimulated by heat. Both the burn of energy in brown fat and the release of energy from white fat are supported by healthy
thyroid function.

Let’s revisit the five major players for a moment, because they are the keys to using food to sculpt your body the way you want it. Feeding your liver, soothing your adrenals, maximizing pituitary and thyroid function, and tweaking your fat balance—all of these are the cornerstones of a Fast Metabolism.

Simply changing the way you eat will mobilize and facilitate healthy hormonal responses to stress, boost the metabolism, and maximize the body’s efficient and balanced distribution of fat, water, and muscle. In a very short time, you’ll be able to behold the amazing power of food, right in your own mirror!

“How do I know I have a slow metabolism?”

This is one of the most common questions I get, and it’s the key reason I like my clients to get some basic
tests before they embark on the Fast Metabolism Diet, to see just how out of balance they are. The tests aren’t necessary to benefit from the Fast Metabolism Diet, but they can help you to understand exactly where you are and how far you need to go.

I recommend these lab tests with a caveat: they are just one part of that peek into the window of the house that is your body. Imagine you’re shopping for a new home. One day, you see a cool house, and you wonder if you should call the Realtor and get a tour of the inside. Before you bother to make the call, maybe you sneak into the yard and take a peek through the window. You see a beautiful living room with vaulted ceilings, hardwood floors, and lots of light. Great! But you can’t view the whole house. The upstairs might be completely trashed, with squatters and rats and graffiti on the walls. Or, the upstairs might be fine. You can’t tell, because you can’t see everything. You can’t learn everything about your health from lab tests, but you can get a preliminary picture.

Also, keep in mind that even if all your tests look great, if you are overweight, out of shape, and eat a poor diet, then your body is doing the very strenuous job of maintaining normal body chemistry under adverse circumstances. I’ve had patients come to see me, and they show me their labs and they say, “Look, everything is normal. I’m fine! The doctor sent me on my way.” I can’t help saying, “But look! You aren’t fine! Just look!”

It’s so frustrating when you are overweight and your doctor tells you, “Your numbers are great, you’re fine; see you next year.” Some of my clients tell me how angry this makes them. “Are you looking at me?” they want to yell. “Do you not
see
me? I am manifesting metabolic dysfunction on my ass!” And they are. So just remember: labs are a peek in the window, but they aren’t everything because you don’t need a measurable disease to have a slow metabolism. Also, you can have significant symptoms and fall in the “normal” range. You might have perfect labs and a trashed metabolism.
If you have more than 10 pounds to lose, your metabolism isn’t what it could be.

So why bother to test at all? Because some basic tests can alert you to health problems you might not know about, or might tell you that you’re doing pretty well and you really only need a little kick in the pants. Labs aren’t the whole picture, but they can provide you and your doctor with some helpful hints.

And speaking of your doctor, this is the time to partner with a doctor who is open to your efforts to lose weight and boost your metabolism, if you don’t already have one. There are many great
doctors out there. I’m in a unique setting in my offices because I work with some of the most amazing doctors every day, and I have access to a lab right in my clinic. This might not be so easy for you. If your doctor balks at doing tests, tell him or her that your nutritionist requested them. Some labs will now do tests for patients without a physician referral, so that’s another option, if it’s available to you. None of the tests I mention below are particularly expensive or unusual.

The main thing I look for in tests, beyond abnormal numbers, are numbers that indicate a fast metabolism because “normal” test results are typically pretty wide. Knowing your numbers will tell you whether you have the chemistry of a person with a slow metabolism, or the chemistry of a person with a fast metabolism, or whether you fall somewhere in the middle.