Metabolism 101

What Your Metabolism Really Is

Your metabolism is the collection of chemical processes in your body that turn food into energy. It’s how your body fuels everything you do, from breathing and thinking to digestion, movement, and recovery. 
 
At its core, metabolism determines how efficiently your body uses energy. 
 
What Does Your Metabolism Do?

Your metabolism is responsible for: 
• Converting food into energy your cells can use 
• Supporting vital functions like breathing, circulation, and organ function 
• Powering movement and physical activity 
• Repairing tissues and building muscle 
• Regulating body temperature 
• Managing hormones and blood sugar levels 
 
Even at rest, your body is constantly burning energy to keep you alive. This is called your resting metabolic rate (RMR) and it makes up the majority of the calories you burn each day. 
 
What Affects Your Metabolic Rate? 

Your metabolic rate isn’t fixed. It’s influenced by several internal and lifestyle factors: 
 
1. Muscle Mass

Muscle is metabolically active tissue, meaning it burns more energy than fat, even at rest. The more lean muscle mass you have, the higher your resting metabolic rate tends to be. 

2. Age

As we age, we naturally lose muscle if we don’t actively work to maintain it. This can lower metabolic rate over time, which is why strength training and adequate protein become increasingly important. 

3. Hormones

Hormones play a major role in metabolism, including: 
• Thyroid hormones 
• Insulin 
• Cortisol (stress hormone) 
• GLP-1 

Hormonal imbalances, chronic stress, and poor sleep can all impact how efficiently your body uses energy. 

4. Nutrition Intake

Eating too little for too long can cause the body to conserve energy, slowing metabolism. Adequate protein intake helps preserve muscle mass and supports a healthy metabolic rate.

5. Movement & Daily Activity

Exercise matters, but so does everyday movement. Walking, standing, stretching, and general activity throughout the day all contribute to total energy expenditure.

6. Sleep & Stress

Poor sleep and chronic stress can disrupt hormones that regulate hunger, blood sugar, and energy use, making it harder for your metabolism to function optimally. 
 
Important to Know

Your metabolism is adaptive, meaning it responds to how you fuel, move, rest, and manage stress. Supporting your metabolism isn’t about extreme dieting or over-exercising; it’s about building habits that allow your body to feel safe, fueled, and supported.