Weight Gain vs. Weight Loss: How is it all balanced? PART II
by Professor Jay
Body’s Energy Homeostasis as it relates to weight gain and weight loss.
Just like everything else, our bodies also have to maintain an energy homeostasis. Energy is necessary for anything to happen. Energy comes in many forms, such as electrical, light, heat, and chemical. The first law of thermodynamics says that energy can neither be created nor destroyed; energy simply changes from one form to another without loss or gain. For example, when you turn your light switch on, charged particles, known as electrons, move through the wire to produce electricity (electrical energy). When that electrical energy reaches the light bulb, it is converted to light and heat energy. No gain or loss of energy, just a different form.
Food contains energy known as chemical energy. Gasoline also contains chemical energy. If you literally burn food by setting it on fire, the chemical energy is converted to heat energy. We can directly measure that heat energy produced to determine the amount of chemical energy in that food. The amount of heat energy in food is measured in calories. The definition of a calorie is the amount of heat energy it takes to raise one liter of water by one degree Celsius. Yes, a calorie is a measurement of heat.
Amount of Calories (Energy) in Proteins, Carbohydrates, and Fats
Overall, there are six classes of essential nutrients.
- Lipids – fats and oils
Of these six, the three that we derive our energy from are carbohydrates, proteins, and fats. A popular misconception is that we get energy from taking vitamins. We don’t get energy from vitamins, but vitamins do play a big role in helping us utilize the energy in carbohydrates, proteins, and fats.
Protein and carbohydrates both contain four calories per gram. Fat contains nine calories per gram. For example, a plain M&M weighs about a gram. So if you had an M&M made of all protein or all carbohydrate it would be about four calories. However, an M&M composed of all fat would be nine calories.
Fat contains over twice the amount of energy as protein and carbohydrate. Since fat is such an efficient way to store energy, we store our excess energy (calories) as fat. So even if we only eat protein and carbohydrate calories, any extra calories that we don’t burn will be converted to fat and stored as energy in our fat cells.
Is it possible to get fat by only eating fruits and vegetables?
Absolutely. Fruits and vegetables are primarily carbohydrates (sugars). For every gram of carbohydrate you eat, you are getting four calories. Here is a very simplified example to illustrate this for you. If you eat two thousand calories of fruits and vegetables and only use eighteen hundred calories, your body will covert the two hundred unused carbohydrate calories to two hundred fat calories and store it in your fat cells.
It is important to get your calories from a balance of proteins, carbohydrates, and fats. It’s not the calorie itself that is different in proteins, carbohydrates and fats, because remember a calorie is just a unit of energy. The difference is what comes packaged with the calories.
For example, let’s say it has been determined that if you eat fifteen hundred calories per day you will lose weight. Based on that, which one of the following meal plans would help you lose the most weight? Assume the portions for each are so that both plans equal fifteen hundred Calories.
Meal Plan A Meal Plan B
chicken breast cake
broccoli ice cream
salad French fries
Some of you might be inclined to pick Meal Plan A because it sounds healthier. Well, Meal Plan A is healthier, but the reality is that you would lose an equal amount of weight on either plan – again assuming that you would lose weight eating fifteen hundred Calories.
How can this be? Again, remember a calorie is just a unit of energy. It doesn’t matter where it comes from. Your cells can only treat it as a unit of energy and nothing else.
Why is it healthier, then, to eat Meal Plan A if I can lose an equal amount of weight on either?
It all has to do with what the calories are package with. Remember, there are six classes of nutrients. All are essential. With Meal Plan B you are mainly getting only two of the six, carbohydrates and fats. In Meal Plan A, you are getting all six. That is why it is important to get your energy nutrients in a balanced manner.
If you choose to lose weight on Meal Plan B, you would end up with vitamin and protein deficiencies and become very ill. Just because someone is thin does not mean they are healthy.
What many obese individuals do is eat both meal plans. In this way, they are getting all of their essential nutrients, however the total calorie amount is too much and will be stored as excess energy (fat). Storing excess energy disrupts homeostasis, and again leads to diseases such as heart disease and diabetes.
It is essential to eat a diet that includes food combinations that naturally balance the intake of energy nutrients.
What do we need energy nutrients for?
We take in food (chemical energy), and our cells use the energy to build stuff, break stuff down, move stuff around, etc. As you read this, every single one of your cells (brain, heart, muscle, skin, kidney, liver, etc.) are using energy to make stuff, break stuff down, and move stuff around. This is called metabolism. At rest your cells require a certain amount of energy for maintenance. This is your resting metabolism. Even when you are sleeping, each one of your cells is using energy to maintain basic functions. There are many things that affect this resting metabolism, for example, the amount of energy (calories) you are using at rest. Of course, with no surprise, everyone’s resting metabolism is different.
So just to make sure you are clear on this, you burn calories as you sleep, as you lie there silently, and even as you attempt not to move a muscle. The amount of calories that you are burning is the amount of energy your body needs to maintain itself at absolute rest (resting metabolism).
Now with that said, keep in mind that with every additional muscle movement beyond lying totally still, you increase the amount of calories that you burn. The greater the movement, the greater amount of calories that you burn.
*The last sentence is worth a repeat: The greater the movement, the greater amount of calories that you burn.
All of the following activities and movements burn additional calories. (Please excuse my attempt at the Dr. Seuss spin, but I couldn’t resist.)
Additional calories I burn, as I…
Reach for the TV control
Get out of my chair
Comb my hair
Climb a stair
Talk to someone new
Tie my shoe
It’s really everything
And anything that I choose to do!
Energy homeostasis is the balance between the amount of energy you bring in, and the amount of energy your cells use at rest, with movement, and during activities.
Remember, the first law of thermodynamics states that energy can neither be created nor destroyed. This means that if extra energy is either taken in through eating, or if extra energy is used through activities and movements, then that energy has to be accounted for. That is where fat storage comes in. When more energy is taken in through food consumption than is used through resting metabolism and activities then the extra energy is converted to fat and stored in fat cells.
When more energy is used on resting metabolism and additional activities than is consumed the stored fat is then broken down and used to support the additional activities. Of course, as the fat is broken down it disappears. This translates as weight loss!
And just like all the “fundamental needs”, energy homeostasis has specific mechanisms (fixers) in place to keep the proper balance between energy deficits and excesses. When there is a perceived energy deficit, the hunger drive kicks on. When there is energy excess, the hunger drive is suppressed, the satiety drive turns on, and your body is prompted to stop taking in energy (eating). When you consciously override the satiety signal and take in excess energy through unnecessary food consumption, your body responds by storing the excess energy as fat.
Overall, each of us is unique. We all have different metabolisms. Some of our homeostatic fixes may not be working as efficiently as they are supposed to. In addition, each of us reacts to foods in different ways. We have different preferences for foods. What might be the best food choices for one is not going to be the best food choices for someone else. As we understand genetics better, this is becoming clearer.
Therefore, in order to keep your body in energy homeostasis you must first learn what works best in your body. A great place to start is with a balance diet such as The Weight Loss Plan for Parents. You will see that this plan incorporates a way for you to adjust to your own needs. It teaches you how to customize for your body.