The hormones that make up your metabolism

For most of us, when we think of metabolism, we think calories and exercise. Eat less and exercise more to boost metabolism and lose weight because it has been fed to us for so long, that this is the way.

Unfortunately, it’s not that simple and energy expenditure and energy intake are only one piece of the puzzle, aswell as being an inaccurate one. The calories in, calories out model is a deceiving oversimplification of how the body uses energy. It is also a marketing tool that has been used to promote unhealthy, processed and damaging foods. A calorie is just the amount of energy required to raise the temperature of 1 kilogram of water 1 degree celcius, when the food is sealed and burned to ash inside a container surrounded by water. A calorie is not an object. A calorie is just energy. In food, it is potential energy. In the real world and outside a lab, calories are subject to millions of variables. – since each person has a unique body and biochemical makeup – so what a calorie does in your body and my body is completley different. Not to mention, all calories are not equal in different foods. What really matters, much more than the calorie number you consume is how you burn the food and distribute the energy, once it gets inside you. The idea of 200 calories for you is the same as 200 calories for me is ridiculous for that reason, so why bother even think of it that way!

Let’s start with an official definition of our metabolism.

“Metabolism is a process, specifically the metabollic process consists of chemical reactions that occur in the cells of all living organisms to sustain life. It is the transformation of our food into either heat or fuel or substance (muscle, fat, blood, bone) At any given moment, your metabolism is either burning, storing or building.”

When we get a flat tire, we fix it. We don’t drive around on the rim for thousands of miles, ruining our car right? The same should be true of our metabolism. The problem is, unlike with a flat tire, sometimes we don’t even know when our metabolism is broken or running less than efficiently.

When our metabolism is broken, we are stuck in fat storage mode, where the body cannot use the food we eat efficiently and turn it into fuel so it is stored as adipose tissue. This is especially pertinent for women over 40 as hormones change. A broken metabolism can lead to insulin resistance, diabetes, heart disease and dementia but the good news is, once we aware of it and the hormones that work to make your metabolism run, we can start the journey to fix it.

Let’s consider first why our metabolism may have slowed down or become less than efficient in the first place. Yo-yo dieting, nutrient-void foods, toxins in our environment, life stage, sedentary lifestyle and high stress can slow our metabolism. So many things affect how we burn these “calories” for fuel on an individual basis.

Do you have a broken leg and your body needs more energy for repair?

Did you sleep well last night?

Have you gone four days without a bowel movement?

Are you dehydrated?

Have you moved from your desk or chair in the last 7 hours?

All examples of these basic things affect how efficient your metabolism is on a daily basis.

In general, the nutrient density of your food. when you eat it, how you eat it, stress levels – physical, emotional, environmental and mental stresses, current body composition, exercise routine, toxins in your food, products and environment, current life stage, body composition all play a part.

If you consider your body to be like a house, let’s look at the structure and what we need to know is going on within this structure. The 5 major players in this structure are your liver, your adrenals, your thyroid, your pituitary and your body substance i.e. white fat, brown fat and muscle. For the sake of this blog post, I will just give a brief overview of each relative to your metabolism.

Liver: Over 600 known metabollic functions happen via the liver. Every nutrient, chemical, hormone needs to be bio-transformed or made active by the liver. Because the liver is so crucially linked with metabolism, it is one of the most crucial organs to nurture to boost metabollic rate.

Adrenals: Your adrenals are small glands on the top of your kidneys and they secrete hormones that regulate your bodies response to stress of all types: physical, emotional, environmental and mental. The level of these hormone determine how you access fuel and what you do with the fuel and the food you consume. Do you store it or burn it and at what level?

Adrenal exhaustion can occur when the body is under any type of the stressors for a long period of time. The bodies response is to protect in this case and so slows down the burning of fuel for energy but stores it as fat to protect.

The thyroid: The thyroid is the metabollic superstar. It is a butterfly shaped gland located at the centre of the throat. I think of it as the furnace of the hormones. The pituitary gland in the brain is like the thermostat, the hypothalmus is like the guy that controls the thermostat and the thryoid is the furnace and the hormones it produces like T3 and T4 are the heat. If any of these 3 mechanisms isn’t working just right, then the rate at which the body burns fuel will be off. T3 is the most important of these hormones and has about 4 times the metabollic strength of T4. These hormones are responsible essentially for converting oxygen and calories to energy. There is a hormone called RT3 or reverse T3 that plays havoc with metabolism and blocks healthy T3 functioning. In chronic stress, nutrient deprivation, certain disease processes, RT3 increases and throws a bucket of water essentially on your metabollic process in a panicked effort to save your fat stores to protect. Sometimes, thyroid diseases can develop like Hashimotos, graves disease when the thyroid hormones are under or over secreting, which leads to great problems with metabolism and many times, these are undiagnosed with people for years.

Pituatary: Controlling the furnace (Thyroid) is the pituatary gland and controls the secretion of TSH – Thyroid stimulating hormone which affects the thyroid hormones. The pituitary also regulates the sex hormones such as oestrogen, progesterone, testoserone and DHEA. The regulation of each of these aswell as your adrenal hormones is crucial to the speed of your metabolism.

Your body substance: Fat, bone, connective tissue and muscle. The body stores your reserve fuel in either muscle or fat. There are two types of fat and for decades scientists believed that the brown fat was only present in infants and small children to help keep them warm and maintain their body temperatures. It is now proven with research that in adults brown fat plays a crucial role in maintaining metabolism rate and blood sugars. Brown fat is brown because it is rich in mitochondria, which are the energy centres of the cell. The more excess weight you have, the higher proportion of white fat you will have.When your metabolism slows down, your body goes in to super white fat production. Brown fat on the other hand helps stimulate metabolism by warming the body, increasing blood flow and making it easier to deliver nutrients to the white fat. Brown fat helps regulate your cholestrol, transports waste to the intestines for elimination, makes 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 behind the shoulder blades, up and around the neck and under the collar bone. If you think about typical places you also hold your stress, its in the shoulders and neck and stress hormones directly affect brown fact activity. Brown fat also seems to be stimulated by cold therapy which I talked about in my hot and cold therapy post.
With regard to muscle, I think most of us are aware that when we increase muscle mass, we boost resting metabolism, given muscle is the most metabolically active.

So to summarize, feeding your liver, soothing your adrenals, mazimizing pituitary and thyroid function and tweaking your fat & muscle balance – all are cornerstones to a fast metabollic rate.

Within that structure, the road to fixing your metabolism also involves looking at the 8 metabollic hormones within this structure to see what is going on. The 8 hormones: oestrogen, insulin, leptin, Ghrelin, cortisol, thyroid hormone, testoserone and growth hormone. Each of these hormones is interconnected and interdependant with the foods you consume & lifetsyle you lead daily.

8 Metabollic hormones

Let’s look at each of these hormones in turn & just learn a little more about them.


When we think of oestrogen, we think of female sex hormones and it is the most important female sex hormone. It is mainly produced by the ovaries, and is involved in regulating the female reproductive system. It can also be made in the adrenal glands and fat cells.

Both very high and low levels of estrogen can lead to weight gain. This depends on age, action of other hormones, and overall state of health.


Insulin is the main fat storage hormone in the body. It tells the cells to either store fat or use the fuel as energy, depending on what the body needs at the time. It is secreted in small amounts throughout the day and in larger amounts after meals. When our cells become insulin resistant, our blood sugars and insulin levels go up significantly, which is very common. Many of us are insulin resistant and actually not aware yet. Over time, chronically elevated insulin levels is what leads to diabetes, metabollic syndrome and weight gain.

Over eating refined sugar, carbs and processed food are mainly what drives up our insulin levels and makes our cells insulin resistant.

There is often a cross between Oestrogen dominance and insulin resistance connected to fat loss resistance. When you are insulin resistant, it means your cells can’t absorb the extra blood glucose, your liver converts this extra glucose into fat. These fat cells are stored and they make oestrogen, which in turns wreaks havoc on your ability to burn and lose fat. To make matters worse, in your early 40’s you become resistant to oestrogen and you become more oestrogen dominant, worse in menopause. Put this all together and it is more clear why after 40, many women are more resistant to fat loss.


Think of Leptin as the one that makes you feel full and it is produced by your fat cells. Leptin tells the hypothallmus in your brain that there’s enough fat in storage and no more is needed, which helps prevent overeating. So it’s a vicious circle when it comes to Leptin as because it is produced in your fat cells, the more adipose tissue or fat storage you have, the higher the leptin level in your blood. You would think that if leptin reduces appetite, then high levels of leptin should mean you start eating less and lose weight. Unfortunately, in obesity the leptin system doesn’t work as it should – leptin resistance, just like insulin resistance above.

Leptin levels are also reduced when you lose weight, which is one of the main reasons it is so hard to maintain weight loss in the long-term.

Two potential causes of leptin resistance are chronically elevated insulin levels and inflammation in the hypothalamus.


I always think if the word “hangry” when I think of Ghrelin. Ghrelin is in fact the hunger hormone. The one that is secreted fueling your cravings. It is produced in the cells of the Gastrointestinal tract, especially in the stomach and is telling the body to eat more. Two key ways of lowering your “hangry hormone” is of course avoiding lots of refined sugar which immediately increases ghrelin production / impairs the ghrelin response. Protein also with each meal can reduce the ghrelin levels and promote sateity.


We all know Cortisol as the stress hormone right and it is in fact the master hormone, in that when cortisol levels are elevated, it affects the signalling of every other hormone, which is why when we are in a chronic state of stress or inflammation, it is hard to lose weight.

Did you know also that excess Cortisol can actually shrink the hippocampus in the brain. Keep in mind that you are already producing more cortisol as you age, even more important to eat and have a lifestyle to lower cortisol levels as we get older. Chronic stress not only change your appetite and the types of food we crave, but it also leads to losing sleep, drinking more alcohol and getting less exercise.


The thyroid is a small, butterfly-shaped gland located in your throat, just behind your Adam’s apple. Because it serves as the body’s thermostat — continuously regulating things like temperature, hunger levels and energy expenditure — thyroid problems can cause widespread symptoms.

Surprisingly, it’s estimated that more than half of those with thyroid hormone imbalance (60 percent) in the world suffering with thyroid issues are completely unaware this is the root of their problems, including weight gain or fatigue. If you get your thyroid hormones tested with the GP, you would just get an indication of TSH- thyroid stimulating hormone and T4 – the inactive form. We need levels of T3 – the active one and reverse T3 to get a full picture of the functioning of your thyroid. A full thyroid panel is a test we offer in clinic.


When we think of testoserone, we think of the male hormone. Testosterone has two main effects on your body tissue – it helps you develop and maintain male characteristics such as hair growth, voice deepening and strength. It also has androgenic effects that include slowing down protein breakdown and speeding up protein metabolism – big regulators of metabolism.


Some of you will have heard me going on about HGH or Human growth hormone with intermittent and water fasting. The recent research has shown that intermittent fasting boosts the production of this hormone aswell as autophagy, which is the renewal of the cells. I will do another blog post for sure on fasting seperately and the different types, pitfalls and benefits.

HGH is naturally produced in the pituitary gland at the base of the brain and plays a vital role in out metabolism. It basicly helps you burn fats and gain lean muscle and determines how much visceral fat you have (belly fat) When it is secreted into the blood, for just a few minutes, allowing just enough time for the liver to convert it into growth factors, which have growth promoting properties for every cell of the body. In women, HGH starts to decline as early as your 20’s. So over 40’s it is important for us women to be aware of Growth factor and boost it’s production.

Of course, these hormones are all intricatley interconnected and when one is out of balance, it throws the others out of balance, especially with the master hormone, cortisol.

This is an area of speciality in my clinic and my metabolism reset program, which I am working on, will be a personalized program based on your initial consultation and will be focused on balancing each of these hormones in turn, that is best for your profile. It will be an option and your choice to do basic metabollic testing of hormone levels, liver and /or gut function and this will be dependant on your circumstances, medical, family history, life stage.

Look out for my hormone reset program in the coming months. In the meantime, you can book a normal consultation with me or a free discovery call to see how I can help HERE