The body’s metabolic rate encompasses varying components:

• Basal metabolic rate (BMR) which refers to the amount of energy expended while ‘at rest’. All of those vital activities your body pursues for homeostasis (simply existing). Blood circulation, hormone regulation, and believe it or not, breathing, accounts for approximately 60-75% of total daily energy expenditure. Factors including body size, amount of lean muscle tissue, body fat percentage, diet, age, gender, hormones, genetics and much more influence your BMR. Some may know this as the speed of your metabolism.
• Resting metabolic rate (RMR) is sometimes confused with BMR and the two are often used interchangeably, but RMR includes the additional, low intensity activities on top of your BMR. This includes activities like a gentle walk, shivering or sweating, and going to the toilet.
• Thermogenesis which accounts for 5-10% of energy usage. It is the energy your body uses to aid digestion.
• Physical energy expenditure refers to the energy burned through daily movement. It’s a common misconception that physical activity only refers to high intensity cardiovascular activity, in fact, it also includes everyday activities including fidgeting, or housework!

People with a slower metabolism tend to burn fewer calories at rest than people who have a fast metabolism, and the human body is designed to store any excess energy in fat cells. This means that if you consume a higher number of calories per day than your unique BMR naturally burns, your body will store the excess calories as fat, which can lead to weight gain.

There’s an age-old myth that people who live with obesity have a slow metabolism. In reality, people living with obesity often need to expend more energy to maintain homeostasis. This can lead to a common experience called a ‘weight plateau’, which you can read more about here. The speed of your metabolism can be influenced by genetics, but small changes to routine can rev up your metabolism.

A high protein diet presses the gas pedal on the metabolism, as it takes the body longer to break down and digest protein, increasing the energy used during thermogenesis. This, combined with regular interval training, can keep your metabolism geared up throughout the day.

Calories burned at rest is unique to everybody. Use an online BMR calculator to understand how many calories you need a day to simply exist…it might surprise you!

Leptin and ghrelin are hormones key to regulating the body’s metabolism. Think of these as your engine oil or fuel, essential to the smooth operation of your engine.

Leptin is a hormone produced by fat cells, central to appetite suppression and management of metabolic rate. This human fuel gage conveys essential information to the brain on how much energy you have left. Leptin levels rise as body fat levels rise, increasing BMR and triggering appetite suppression, which can induce fat loss. Leptin resistance, when leptin production is high but the body doesn’t know what to do with it, accelerates hunger cues and is recognised as a major biological contributor to obesity.

Ghrelin, leptin’s counterpart, is known as the hunger hormone. Levels fluctuate throughout the day, activated by an empty stomach and signalling hunger to the brain. After eating, ghrelin is reduced. A healthier diet inclusive of enough carbohydrates and protein can reduce the amount of ghrelin released into the bloodstream, compared to when fats are consumed. Higher ghrelin levels are common in people living with obesity, which leads to stronger feelings of hunger.

When your engine light flashes up, your fuel gage is low or your tyres need some air, continuing to drive won’t help the problem go away. In fact, it would likely trigger other issues.

People living with obesity can be at an increased risk of metabolism related illnesses, including metabolic syndrome (MetS), a cluster of conditions impacting the metabolism and cardiovascular health in tandem. These conditions can increase blood pressure, blood sugar, and body fat around the waist. Insulin resistance is the hallmark symptom of MetS, defined as the most important predictor for future development of type 2 diabetes and risk factors associated with cardiovascular diseases.

While obesity is central to the development of MetS, not all who live with obesity will develop MetS.

The metabolism is complex and unique to everyone, and reaching a point where your metabolism is at optimum performance for your own body type can take time. Seek support from your healthcare professional today to understand how you can maintain a healthy metabolism, and manage your weight and any weight-related health issues in a way that works for you.