Demystifying the Metabolic System

A slow metabolism is sometimes blamed for a wide range of complaints – weight gain, fatigue, dull skin and more. But what really is “metabolism”, how is it measured, and how can we optimize it?

Your body is an incredible machine that is able to take the energy from the food we eat, and transform it into energy our cells can use. Simply put, the combined reactions that make up this process is our metabolic system, also termed metabolism. Our metabolism is not just how fast or how slow we burn calories (aka our metabolic rate).

At a high level, we can break our metabolic system into two overriding categories: the breakdown of energy and nutrients (catabolism), and the building of tissues and energy stores (anabolism). The breakdown of food during digestion would be a catabolic reaction, while the storage of fuel in the form of fat would be an anabolic reaction. Our body is in a constant flux between these states depending on a wide range of factors like our nutrient status, the time of day, what we’re doing at the moment, hormone balance etc.

There are thousands of reactions involved in our metabolism; from breaking down the energy from food to converting that energy to fuel for our cells, and finally, clearing out waste products. Three of the most important pathways for energy production are glycolysis, the citric acid cycle, and the electron transport chain. Together, these pathways take glucose from our food to create energy in the form of ATP molecules. These small but mighty molecules of ATP then go on to power virtually everything we do: from making new cells to tissue repair to brainpower to movement!

Having a strong metabolic system, or what scientists call ‘metabolic integrity’, is truly at the foundation of feeling, looking, and performing our best. When metabolic integrity is seriously and/or chronically compromised, metabolic syndrome can occur with the telltale symptoms of increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels. But aside from clinical conditions, what are indicators that our metabolism is working optimally?

Indicators of Metabolic Integrity:

  • Healthy Digestion

Metabolism starts with the breakdown and extraction of energy and nutrients from food. A well-oiled digestive process will ensure that those nutrients (such as glucose, which we know is the substrate for glycolysis) are feeding our metabolic pathways for energy.

  • High Mitochondrial Function

Our mitochondria are termed the “energy powerhouses of the cell”, and for good reason. So many key processes like the citric acid cycle and the electron transport chain rely on the machinery of the mitochondria. If these intracellular organelles are not working optimally, then the energy from our food won’t be efficiently converted into energy that we can use.

  • Balanced Blood Sugar Levels

Our body carefully tracks how much glucose is available and regulates blood sugar accordingly. Higher glucose (such as after eating) will be metabolised and stored, while lower glucose (such as fasting or after exercise) stimulates our cells to tap into our stores. As glucose is so key to our metabolic pathways, our blood sugar balance is essential for maintaining a healthy metabolic system.

  • Balanced Hormone Levels

Hormones like insulin, estrogen, testosterone and growth hormone are the signals to when we should store energy (and where and how) as well as when we should break down our stores and shuttle those nutrients into our metabolic pathways. Dysregulation can occur due to many internal factors as well as our lifestyle habits.

  • Balanced Neurotransmitter Levels

Neurotransmitters also provide signals that direct our metabolic processes. Unlike hormones, neurotransmitters can have faster but short-lived effects. Epinephrine and norepinephrine act as neurotransmitters that regulate the body’s “fight or flight” response. This involves preparing the body with the energy it may need in response to stressors.

  • Proper Excretion of Waste

Our metabolic pathways supply our cells with the nutrients and energy they need. However, these pathways will often create waste products that our body has no use of and must excrete in a safe and timely manner. Metabolic waste products include carbon dioxide (CO2), urea, and ammonia. Backlogs in excretion processes can leave us feeling very poorly, and over time can severely damage our excretion organs and overall health.

It might seem like a lot can go wrong and sabotage your metabolic system. In a way, that’s true, but our everyday lifestyle choices affect each and every one of these indications. Therefore, we have a remarkable ability to optimize our metabolic pathways, and a responsibility to keep it working in top condition.

In Functional Medicine, there are many indicators of sub-optimal metabolic health. Some of these may present as noticeable symptoms like fatigue, unexpected changes in weight, hair loss, frequently feeling cold, dry skin, low mood, headaches, and brain fog. However, laboratory testing is essential to checking your metabolic health as well as helping to pinpoint the specific pathways that can be optimized. The best test to assess metabolic integrity is an Organic Acids Test (OAT). With a simple urine sample, this test analyses chemical by-products of key metabolic reactions. With this data, we have a snapshot into how smoothly your chemical pathways are working and how to optimize your metabolism.


Contact us to learn more about your metabolism and how to support your body to achieve your life goals.


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