Say what you will about getting older, but at least it is thoroughly democratic; no matter how healthy your diet, lifestyle and overall appearance might be, everyone eventually succumbs to Father Time’s onslaught. The telltale signs of aging, such as graying hair, wrinkles and sagging skin, are nearly impossible to miss. Unfortunately, the long reach of the aging process doesn’t stop with our cosmetic appearance, as the body’s cells and tissues undergo dramatic changes.
Changes at the Cellular Level
When reading health-related articles, you might have come across the term “tissues” to describe the makeup of tendons, ligaments and other parts of the body. The reason why this term pops up so often is that various tissues are found throughout the body, and are essential cornerstones for everything from vital organs to joints. Needless to say, the body’s various tissues are adversely affected when age starts to make its presence felt. Doctors classify these many tissues into one of four basic categories:
Connective Tissue – True to its name, the purpose of connective tissues is to connect other types of tissues to one another. In doing so, connective tissues keep organs lodged firmly in place, and simultaneously act as a supporting framework for epithelial tissues. These tissues also allow unimpeded passage through the body to various blood vessels and nerves.
Epithelial Tissue – If you want to see what epithelial tissue looks like, simply take a look into the mirror. Or you could simply look at your arms and hands. As you can probably figure out from reading the previous two sentences, your skin consists of epithelial tissue, as does the lining of your vital organs, major cavities and gastrointestinal system.
Muscle Tissue – There are three types of muscle tissue within the body. Whenever we make a conscious movement, our striated muscles are used to move our bones in the desired direction. Involuntary muscles, which operate without us consciously thinking about them, are needed to help internal organs function properly. The final type of muscle tissue, the cardiac muscle, is found in only in the heart wall (most of the heart wall consists of this kind of tissue). Cardiac muscle tissue operates in an involuntary manner.
Nerve Tissue – You might remember learning about nerve cells during middle school biology class. To briefly recap, nerve cells are tasked with transmitting messages through the body. These cells collectively form nerve tissues, which in turn are used as the building blocks for several major parts of the body, including the brain and spinal cord.
Nerve tissues aren’t the only tissues that consist of numerous cells. In fact, this characteristic applies to every piece of tissue in the body. The cells that form a given section of tissue are all similar in appearance, and combine together to perform a specific role. The health and overall condition of bodily tissues hinges on these cells; should they begin to deteriorate, the tissues they form will likewise begin to wither.
As we progress further and further into adulthood, our cells begin to steadily begin to lose their ability to divide and multiply into fresh cells. Cell division is a crucial function that occurs within the body, as it serves to replace and repair damaged tissues and keep our muscles, organs, bones and other body parts in good standing. Compounding this problem is that pigments and lipids begin to accumulate within the cell itself (pigments give cells and tissues their color, whereas lipids are fatty substances inside cells). These factors can prevent cells from working normally, and may even force them to stop functioning completely.
The body’s tissues soon feel the impact of these cellular changes. The flexibility of our connective tissues gradually vanishes, causing the organs, blood vessels and airways connected to them to likewise become more inflexible over time. Time also does a number on the membranes of tissue cells. Cell membranes are protective barriers for the cell’s inner contents, and also act as the cell’s gatekeeper, determining what substances can enter and exit the cell. With the body’s advancing age, cell membranes become noticeably less effective at their job. Consequentially, tissues struggle to acquire much-needed oxygen and expel waste.
Age and the Vital Organs
Since tissues are made up of cells, and organs consist of linings of tissue, it’s easy to see how declining cellular health can have significant consequences for the body’s organs. In our later adult years, the organs we heavily depend on can function at a significantly diminished pace. The heart provides a good example of how age erodes an organ’s performance capabilities. Up until the age of thirty, a human heart is able to pump roughly ten times more blood than required by the body. The heart activates this mechanism in emergency situations, sending additional blood to the body’s tissues. Each year after the age of thirty, the heart loses 1% of this extra production capacity. The kidneys and lungs also encounter this problem.
The visible imprint left by aging doesn’t occur overnight (though perhaps some people would disagree). Grey hairs, eye bags and crow’s feet tend to make their unwelcome appearance over a prolonged period of time. By the same token, it can take years before the impact of corroding internal tissues become readily apparent. Such a scenario can prove to be very dangerous to unsuspecting older adults, who could suffer from heart failure or other serious ailments if they overburden weakened organs.
What is to Blame?
You may think that after decades of study, doctors would have a fairly good idea as to what causes the human body to age. In reality, medical science has yet to determine why the body changes so dramatically in its later years. Most gerontologists (health care professionals who study the human aging process) believe that many different culprits might be to blame. Some common factors that may trigger or hasten human aging are listed below:
- A person’s hereditary background
- Environmental influences
- Prior medical history