How Your Metabolism Works

Here's a simplified description of how your metabolism works...

Don't you wonder how your body gets the energy it needs from the food you eat? Hours after you've finished off that steak at your favorite restaurant, your digestion begins. Nutrients in the steak become precious fuel and building blocks required by your body. A complex process called metabolism is responsible for obtaining energy from the food you eat.

What Exactly is Metabolism?

“It's because of my metabolism.” How many friends and family members do you hear attribute (or blame) their sexy figure (or weight problem) to metabolism? Let's face it. Some people view and treat their metabolism as a curse while some regard it as a blessing. Which one are you?
Fat and Skinny Person

Metabolism is basically an assembly or group of biochemical processes, which occurs in the cells of your body. It transforms the molecules in the food you eat into usable energy which enables you to do everything. Thinking, reading, writing, surfing the Net and everything else that you do. Your metabolism is also powering the processes that happen when you are are resting or sleeping. To maintain healthy and functioning cells, several simultaneous metabolic reactions take place.

In essence, your metabolism started way back when you were conceived (when you started life) and it stops when you die. It's a constant process you can't live without.

How the Complex Process of Metabolism Works

Don't worry about the term complex, I'll simplify it for you. Let's say you're eating your favourite chocolate bar (Snickers?). The chocolate is filled with energy. After eating it, your body's next task is to break down the components, such as all that sugar in your chocolate bar. Breaking down the sugar releases energy. Furthermore, the cells of your body use this energy to perform their functions.

When food reaches your digestive system, complex protein molecules called digestive enzymes break carbohydrates into sugars (example, glucose), fats into fatty acids and proteins into amino acids. By the way, protein and fats are also found in your chocolate bar. Both of these can also be utilized as sources of energy when you need them. The fatty acids, amino acids and sugars are absorbed into your bloodstream and transported to your cells.

Inside your cells, more enzymes meet up with these compounds and undergo various chemical reactions. These reactions happen to release energy for immediate or future use. Most of the energy is stored in your liver, skeletal muscles and body fat.

It's a Busy Two-way Street for Your Metabolism

There are two simultaneous activities going on in opposite directions with the process of metabolism. One intends to build and store energy, while the other one intends to release energy for fuel. The first one is known as anabolism, and the second one is called catabolism.

Building Blocks for Cells

Anabolism.
Anabolism is the metabolic process of building. It's like a bodybuilder adding more muscle to his physique. The small compounds are assembled into larger and more complex molecules (fat, protein and carbohydrate). This is done to provide building blocks for growth of new cells, to maintain existing cells and to save up energy for future use. As a result, the bodybuilders muscles grow.
Catabolism.
When the same bodybuilder goes to the gym to lift weights, catabolism happens. Catabolism provides the energy needed to lift those heavy weights. Inside the cells (the muscle cells in this case), energy is provided from the breakdown of large molecules (carbohydrates, fats and lastly, proteins). Waste products are also produced when catabolism happens. Your intestines, kidneys, lungs and skin take care of these for you.

Metabolism and Its Little Helpers

Just like Santa Claus and his little helpers (the elves), your metabolism also gets support and direction from little helpers called hormones. Your endocrine system is responsible for the production of your hormones. Most of them are involved in the speeding up (rate) and directing (break down or assemble) of your metabolism. Examples of these hormones include thyroxine and insulin secreted by the thyroid gland and pancreas respectively. Recent studies have identified certain factors, which affect the production and release of these hormones. Results obtained from these studies will certainly have an impact on how we view and understand metabolism. Stay tuned!

Your BMR

BMR stands for basal metabolic rate. It's a measure of how fast your body utilises (burns) energy while you're resting. If you have a high BMR you burn more calories, while if you have a low BMR you burn less calories. There are many variables which can influence metabolism including height, weight, gender, age and lean muscle mass.

The following are some factors which influence your BMR:

Genetics. Look at your parents. How's their metabolism?
Diseases. Your body's ability to metabolize molecules can be affected by some chronic diseases like diabetes, and heart problems.
Body composition. If you have more muscles, you burn more calories and store less fat.
Food and supplements. There are some foods and supplements which can rev up your metabolism.

Thyroid function. If your thyroid is underactive, your BMR is slower because the thyroid gland releases hormones which help to regulate your metabolism. Click here to see the symptoms of an underactive and overactive thyroid.

Master Your Metabolism

While you can’t completely change your metabolism, there are some things you can do to influence it including dietary changes, correcting nutritional deficiencies, exercise (especially resistance training and high intensity interval training) and ensuring that your hormonal system is functioning optimally. There are also certain supplements which can help to support the metabolism. Understanding and mastering your metabolism will help you to feel good and maintain good health.