Weight Gain vs. Weight Loss: How is it all balanced? PART I
by Professor Jay
I’d like to introduce you to a new term for the word balance, as it applies to physiology. That word is homeostasis. I define homeostasis as a dynamic constancy. I know dynamic means changing, and constancy means constant or not changing. So how can something be constant, yet always changing? Let me explain the oxymoron, dynamic constancy, and how it relates to weight loss.
I teach anatomy (different parts of the body) and physiology (how the different parts of the body work) to nurses, chiropractors, occupational therapists, pre-med and pre-dental students. In physiology, there is a concept known as homeostasis. The concept of homeostasis was first described by Claude Bernard, who is regarded as the father of physiology. Bernard wrote, “The constancy of the internal environment is the condition for a free and independent life.” This is still the underlying principle of homeostasis today.
To my students, I define homeostasis as a dynamic constancy. I explain that with living organisms – which includes us – too little of something will ultimately cause its death and too much of something will equally lead to its death. In other words, each of life’s “fundamental needs” must be within a specified and constant range. (I’m using the term “fundamental needs” to include all the necessities for optimal health, such as nutrients, body temperature, waste regulation, etc.)
However, these “fundamental needs” are constantly changing inside of us each minute throughout the day, depending on our current situation and environment. The inability to maintain homeostasis – that is, keeping all our “fundamental needs” within their proper ranges – is known as disease.
For any organism to be successful, it must be able to recognize whatever has changed and immediately apply a fix to bring the out-of-range “fundamental need” back within normal limits. This is true of all life, and we certainly are no different. It is our body’s job to keep these dynamic or constantly changing “fundamental needs” within a constant range. We have very specific mechanisms (fixes) that keep each of them from getting too high or too low.
Let me give you some examples of “funadamental needs” that are constantly changing, and what fixes are applied to keep them in within a healthy range.
Average body temperature is 98.6 degrees Fahrenheit. However, if you take your temperature five times throughout the day, it will be different each time, depending on variables such as room temperature and your current level of activity. When we are moving around a lot, such as with exercise, our muscles rapidly generate heat. If we didn’t get rid of that heat we would overheat (hyperthermia) and ultimately die.
Sweating, however, is the mechanism (fix) that allows us to get rid of the excess heat. Too much heat is no good. On the other hand, if we were outside on a very cold day, our body temperature would begin to drop. A mechanism (fix) for bringing our body temperature back into the homeostatic range is shivering. Through shivering, which is involuntary muscle contractions, we are able to generate heat, which warms us.
The point is that our body temperature is always changing, depending on our circumstance, but as long as we have the correct mechanisms (fixes) in place we can keep it in the necessary constant range.
If you take your blood sugar level five times throughout the day, it would be different each time depending on variables such as when you had your last meal, how much sugar was in the meal, and your level of physical activity.
When sugar levels get high, which occurs after we eat carbohydrates (sugar), insulin is released by the pancreas to lower those levels. When we don’t eat for awhile, our sugar levels get low, but our liver (which responds to another hormone) fixes the problem by releasing sugar into the blood.
If your sugar levels get too high and stay high because the mechanism to fix it (insulin – which allows sugar to enter cells from the blood) is not working, the result is the disease known as diabetes. If your sugar levels get too low (hypoglycemia), you would not be able to feed your brain cells, and death would result. Just like everything else, we have mechanisms (fixes) in place to keep our ever-changing sugar levels within constant range.
Again, depending on our immediate circumstance, our body’s “fundamental needs” are always changing, and it is imperative that we have all the necessary fixes available to keep them constant over time.
Homeostasis does not apply only to body temperature, insulin levels, and blood sugar levels. The concept of homeostasis applies to everything. Some people refer to homeostasis simply as balance. We always hear people talking about how important it is to achieve balance in our lives. And they are right. In our everyday lives, our circumstances are always changing, but as long as we have our mechanisms (fixes) in place, we can keep ourselves constantly successful.
The energy our body requires to work at an optimal level is no different. We must maintain an energy homeostasis. This energy homeostasis when not balanced translates into weight loss or weight gain. And once again, going too far in either direction does not provide for optimal health.
SEE PART II Weight Gain vs. Weight Loss
To find out how homeostasis fits into weight gain and weight loss.