So how does your body convert the food you eat into energy? It converts it through a continuous process that is committed to breaking down the food and re-organizing this food-rubble into energy, fats and nutrients, and of course, letting go of the extra through a good dump.
So let’s say that you weigh around 80 kg. Most of that – around 64% is water (although by looking you can’t tell that. You always assume that it’s all fat in your body. After water, the second largest proportion that makes up your body is the protein – around 16%. Protein is not only found in the muscles, but it is also found in every one of our 37 trillion cells. Another 16% is fat. Minerals take up another 4% of our body, and guess what? Carbohydrates only account for 1% of your body’s composition.
The first type of the reaction is destroying and reducing the reactants into molecular rubble. The other one reorganizes that particular rubble into bigger products that bring together in order to “create” us. All of this is happening at the cellular level, and these processes make up our metabolism. The break down of food and the consequent chemical processes that turn it into energy is what is commonly referred to as metabolism. In short, we can say “Kujenga Mwili”.
This is how you’re metabolism works
Metabolism involves the break down of substances (catabolism) and the build up of substances (anabolism). Catabolism involves breaking down complex molecules to for simpler ones. It is sometimes referred to as destructive metabolism, for instance when carbohydrates and proteins are broken down into sugar and amino acids respectively. It involves the release of energy.
Anabolism, on the other hand, leads to the production of complex molecules which are then utilized to form cellular structures. Some anabolic processes include the growth of bones and muscles and DNA synthesis.
Simply put, your body is continuously working to break and use nutrients that make the energy in your body.
Nutrients are molecules, kind of like the ones we studied about in high school, chemistry class. It breaks the nutrients’ molecules, and rebuilds them, and breaks them again and rebuilds them, and this whole back and forth process is what keeps you alive, energetic (or not) and hopefully (depending on how well you eat) healthy.
You’ve heard about these nutrients, but we’ll repeat them for the sake of clarity.
- Vitamins– nutrients needed for normal growth and are required in small quantities from the diet since the body can not synthesize them. They help our body to utilize the other nutrients.
- Minerals– chemical elements obtained from the diet necessary for growth and good health. have different functions to different body tissues and components
- Carbohydrates – mainly come from plants and form the molecular fuel that our cells need to produce energy.
- Lipids (fats) – The main functions are insulation for temperature maintenance and carry fat soluble vitamins.
- Proteins- Required for the structure, function, and regulation of the body’s cells, tissues, and organs.
Production of energy in your body
Everything you do requires energy; eating, talking, laughing or breathing uses energy. Our body cells use oxygen to burn glucose to produce energy in the form of ATP – a molecule that stores and transports chemical energy within cells. This energy is then transported from one cell to another to produce the desired effect.
Energy is essentially generated from carbohydrates. Just like money, energy has a “currency” (there are different types of currencies for energy) the most important currency and common one for your body is the ATP.
Apparently, our cells cannot store ATP for long because it’s chemical energy, and so the cells store energy more often in the form of glucose, and generate ATP when they need some real energy to get things moving!
Your cells break down the glucose and convert it into ATP when they need more energy. That’s why after students run a long race, you’ll find teachers giving them a spoon of powdered glucose, they should give them grapes instead, grapes are high in carbohydrates!
Some of your cells can get energy from fats; however, the most critical cells like the red blood cells, are working purely on glucose.
Your liver stores your energy
The body has a very efficient way of storing energy, through a molecule called glycogen. Your liver stores energy in the form of glycogen, which is glucose deposits.
Once glucose appears in your blood, from the digestion of carbohydrates, fats and proteins, you liver kicks in to take up the excess glucose that has remained in your blood after your cells have consumed what they require. This excess glucose is converted into glycogen, an energy deposits, think of it as an energy reservoir in the liver, it’s also found in your skeletal muscles.
Glycogen is not fat, it’s a glucose molecule, potential and excess energy stored for you in the liver or muscle!