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Science Behind the Diet

Click on each phase to explore your body's response to those specific foods

Adrenals

All the yummy sweet fruits and whole grains in this phase will stimulate the endorphins in the brain, which will actually boost your mood, help you with crazy sugar cravings, and even ease you out of your caffeine withdrawal. Because this type of healthy eating supports every function throughout the body the brain begins to recognize that it will have enough nutrients to ramp up the metabolism and ease your body out of storage mode.

Liver

In Phase One, you’re really nourishing your liver, flooding it with nutrients to stimulate its most efficient functioning. In this phase, the liver begins breaking down and releasing the nutrients from the foods you’re consuming. This is what helps increase your metabolism, letting it begin to recover from its sluggish state. When the liver is fed, it also manufactures carnitine, which takes fat and escorts it to the mitochondria—your body’s little fat burners. The amount of carnitine in your system dictates how much fat can be delivered and incinerated. So the faster and more efficiently you produce carnitine in your liver, the faster and more efficiently your metabolism will work.

Thyroid

All these nutrient-dense fruits, vegetables and whole grains like quinoa, oatmeal, and spelt you get to eat in Phase One of the Fast Metabolism Diet also feed your thyroid so it can produce the hormones T3 and T4, the superstars of a fast metabolism. The B vitamins found in lentils, lean beef, turkey, and whole grains also stimulate the thyroid, igniting its thermogenic (fat burn) effect. As Phase One helps to lower the stress hormones, this will promote healthy T4 to T3 conversion of the thyroid hormone reducing the chance of elevated dysfunctional RT3 hormone.

Pituitary

Stabilizing your blood sugar in Phase One of The Fast Metabolism Diet is crucial support for your pituitary, the master gland. The pituitary gland controls hormone functions such as the adrenal hormones, sex hormones, thyroid hormones, and also regulates body temperature. The pituitary gland is quick to respond to positive changes in our environment such as healthy eating, exercise and a reduction in stress. The impact you make in Phase One will be felt in your elevation of mood, increased libido, ability to deal with stress, and fat burning capabilities.

Brain

All the yummy sweet fruits and whole grains you’re eating in Phase One will stimulate the endorphins in the brain, boosting your mood, helping you with crazy sugar cravings, and even easing you out of your caffeine withdrawal. Because this type of healthy eating supports every function throughout the body, the brain begins to recognize that it will have enough nutrients to boost the metabolism and ease your body out of storage mode.

Heart

The cardio you’re going to do in Phase One is terrific for your heart, a smooth muscle, and will help you to burn off cortisol faster. All those natural sugars and healthy carbs will fuel your workouts so you can make them longer and harder, building muscle and burning fat. The reduction of stress hormones in Phase One can help to lower blood pressure, reduce belly fat, increase endorphins, and balance sex hormones—all important factors in preventing heart disease.

Adrenals

Phase Two is for solidifying the balance of hormones for the adrenal glands. Once your adrenals have been soothed, and your cortisol levels seduced into submission in Phase One, your body is now primed to release fat cells from the hips, butt, belly and thighs. The vitamin C in lower-sugar fruits like lemons and limes, and the amino acids in lean meats like white-meat chicken and turkey, lean beef and pork, and venison and elk, all strengthen the adrenal glands. And the stronger your adrenal glands, the less fat-storing hormones they’ll release in times of stress.

Liver

The high-protein, low-glycemic foods in Phase Two are liver foods. Leafy greens are rich in chlorophyll and alkalinizing nutrients that help stimulate the enzymes created by the liver to release fat deposited on the body. Alkalizing, enzyme rich vegetables combined with lean proteins stimulate the liver to break down the proteins into amino acids, the building blocks of muscle. These amino acids are then converted into liver-supporting compounds like carnitine, a powerhouse nutrient that helps the body release stored fat into the bloodstream where it can be metabolized for energy. The beef, white-meat chicken, cod, and asparagus you’ll eat in this phase are particularly rich and carnitine-producing. They help get the fat to the furnace so it can burn.

Pancreas

The heaps of alkalizing greens - like cabbage and cucumbers, broccoli and kale, lettuce and spinach—you’ll pile on your plate in Phase Two prime the pancreas to produce the digestive enzymes it’s going to need later in Phase Three of The Fast Metabolism Diet to burn through that newly released fat. The pancreas also produces the hormone insulin; healthy insulin production insures the metabolism of fats and prevents belly fat storage. By first stabilizing the blood sugar and now promoting digestion and release of fat, the body is being primed to savage fat in those hard to get areas.

Thyroid

The bitter green vegetables you’ll eat in Phase 2 provide a lot of nutrients for the thyroid, to facilitate proper production of those fat-torching thyroid hormones, T3 and T4. The proteins in this phase also feed you selenium, taurine and iodine, which are necessary for proper thyroid hormone production and healthy T4 to T3 (the rock star thyroid hormone) conversion.

Gallbladder

In The Fast Metabolism Diet, Phase Two foods stimulate the gallbladder, which breaks down fats so it can be metabolized and utilized for energy in the body. They prime the gallbladder to release the enzymes that are going to help incinerate the newly released fat from your thighs, hips, belly, butt and chin and breakdown the healthy fat you will be eating in Phase Three.

Kidneys

Diets high in protein that don’t include a lot of alkalizing vegetables can be hard on your kidneys, causing your body to become too acid and putting it into a state of stress. When this happens the body loses water weight and not true fat loss. The magic of metabolism repair in Phase Two is that it combines high protein with a huge amount of alkalizing green vegetables like kale, mustard greens, collard greens, Swiss chard, watercress and arugula. These leafy greens prevent the body from going into an unwanted state of acidity. These veggies hold your PH in check so your body can lay down your muscle efficiently and detoxify stored historical fat.

Heart

The heart is made of smooth muscle tissue, just like any other muscle in your body. So all the protein you’re eating in Phase Two doesn’t just help build up the muscles in your biceps and triceps, it also helps heal and build a healthy heart muscle. Foods in Phase Two are rich in arginine, carnitine and heart healthy antioxidants—all shown to improve cardiovascular function and prevent heart disease.

Muscle

Phase Two of The Fast Metabolism Diet is all about building muscle—and more muscle burns more fat! The nice, steady stream of easily digestible (meaning low-fat) protein will keep laying down the muscle, which is essential because muscle ravages calories. So the more muscle mass you have, the faster your metabolism will be. The green vegetables central to this phase, in addition to being alkalizing, are rich in nitrogen, which is essential for muscle building. The green vegetables ensure that all the protein you’re eating is easily incorporated into your body. And don’t forget you’ll be lifting weights in Phase Two, helping your body build even more muscle.

Adrenals

The fatty fish you get to enjoy in in Phase Three, like salmon, halibut, and tuna, lower levels of cortisol, that fat-storing stress hormone. They help promote healthy sex hormones as well as mood elevation hormones, and they stimulate fat burning enzymes. The yoga, meditation, or massage recommended in Phase Three will not only keep your cortisol levels low, but also increase the circulation of fat burning enzymes to those trouble spots and hard to reach places.

Liver

The fatty fish you get to enjoy in in Phase Three, like salmon, halibut, and tuna, lower levels of cortisol, that fat-storing stress hormone. They help promote healthy sex hormones as well as mood elevation hormones, and they stimulate fat burning enzymes. The yoga, meditation, or massage recommended in Phase Three will not only keep your cortisol levels low, but also increase the circulation of fat burning enzymes to those trouble spots and hard to reach places.

Thyroid

Phase Three foods like seaweed, coconut oil, avocados, cashews, egg yolks, shrimp, and lobster are all thyroid foods, stimulating the release of fat-burning T4 and T3 hormones. Strategically eating these healthy fats create a thermogenic effect in the body, melting those hard fat stores and allowing them to be liquefied by the thyroid hormones, burned for energy, and released from the body. This burn boosts your metabolism and primes the body to be ready for Phase One again.

Stomach

Phase Three foods like seaweed, coconut oil, avocados, cashews, egg yolks, shrimp, and lobster are all thyroid foods, stimulating the release of fat-burning T4 and T3 hormones. Strategically eating these healthy fats create a thermogenic effect in the body, melting those hard fat stores and allowing them to be liquefied by the thyroid hormones, burned for energy, and released from the body. This burn boosts your metabolism and primes the body to be ready for Phase One again.

Fat

In Phase Three of The Fast Metabolism Diet, your fat will be doing one thing: disappearing! All the foods in this phase are specifically chosen because they play a role in boosting your metabolism so it can start torching fat at an incredible pace. All of the organs, hormones and systems are uniquely supported and stimulated at targeted times by strategically eating in Phase One, Two and Three to release, burn and excrete fat for good!

Pituitary

From the first moment you put that buttery avocado or creamy almond butter in your mouth and start chewing, your pituitary gland will begin releasing and regulating hormones that stimulate your body to break down fat. The large quantity of healthy fats you consume in this phase can support the pituitary in causing a dramatic increase in the oxidation of fat, which helps your body to burn even more fat to use as fuel.

Hypothalamus

The yummy "feel full fats" that slow gastric emptying (the rate food leaves your stomach) stimulate the hypothalamus (and pituitary) to signal that you are full and satiated. This can help to lower your stress hormones, make insulin more efficient in releasing fats and create a whole systemic push to a faster metabolism.

Gallbladder

Now that your gallbladder has been primed in Phase Two, any fat that crosses your lips in Phase Three of The Fast Metabolism Diet are easy to break down. The healthy fats stimulate the gallbladder to release a flood of fat-melting enzymes that then chew away your own fat stores.

Brain

The quantities of healthy fats you’re getting from decadent foods in Phase Three like hummus, avocado, nuts, and olive oil stimulate the release of endorphins, the feel-good hormones in your brain that make you feel happy and satiated. Your brain will also feel sharper and more alert; you’ll have better memory, focus and energy thanks to the healthy hormone balance you’ve achieved in this phase.

Heart

The heart-healthy omega-3 fatty acids in foods like fish, walnuts and olive oil keep everything moving slickly and smoothly through the heart, helping to lower cholesterol levels, balance triglycerides, and keep you heart-healthy.

Bowels

In the process of torching all this fat, your body is purging a lot of toxins that were previously stored in that fat, releasing them into the bloodstream. So it’s extremely important to drink a lot of water in Phase Three, to keep your bowels moving. If you don’t release the toxins and excess fat by keeping the bowels moving, they’re just going to get re-absorbed into your body.

Hair

The high healthy fats you enjoy in Phase Three of The Fast Metabolism Diet are full of nutrients that make your hair thicker, shinier and healthier.

Skin

The healthy fats you’re eating in Phase Three are also full of nutrients that promote healthier skin. Plus, the dry skin brushing recommended during this phase increases blood flow to the areas of the body with surface fat, allowing the enzymes to go directly to the cellulite and annihilate it!