Aging Types, Causes, and Prevention

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Aging is something we all do but understand very little about. Sure, it's easy to make a list of all the changes that come with age—memory loss, wrinkles, and lean muscle loss—but no one really understands what aging is, why it happens, and whether we can actually slow or stop it.

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What Is Aging?

Think of aging as "that which happens to our bodies over time." This definition encompasses the multiple processes that the human body goes through as it ages (as opposed to the signs of aging, such as gray hair and wrinkles).

Some aging is caused by the body, such growth spurts children go through during puberty. Aging can also be accumulative, such as the onset of skin damage due to excessive sun exposure.

Aging is ultimately a combination of physiological changes in our bodies and the environmental factors we are exposed to. While the latter is often beyond our control, some environmental factors are modifiable and may influence the course of aging.

Types of Aging

Digging deeper into the process of aging, there are several theories that describe how and why our bodies age on multiple levels.

Cellular Aging

A cell can replicate about 50 times before the genetic material is no longer able to be copied accurately. This replication failure is referred to as cellular senescence during which the cell loses its functional characteristics. The accumulation of senescent cells is the hallmark of cellular aging, which in turn translates to biological aging.

The more damage done to cells by free radicals and environmental factors, the more cells need to replicate and the more rapidly that cellular senescence develops.

Hormonal Aging

Hormones play a huge role in aging, especially during childhood when they help build bones and muscles and facilitate the development of secondary male or female characteristics.

Over time, the output of many hormones will begin to diminish, leading to changes in the skin (such as wrinkles and the loss of elasticity) and a loss of muscle tone, bone density, and sex drive.

Because sex hormone levels differ between females and males, how females and males age also differs.

Accumulative Damage

Aging caused by accumulative damage (i.e., "wear and tear") is about the external factors that can build up over time. Exposure to toxins, UV radiation, unhealthy foods, and pollution can just some of the things that can take a toll on the body. 

Over time, these external factors can directly damage DNA in cells (in part by exposing them to excessive or persistent inflammation). The accumulated damage can undermine the body's ability to repair itself, promoting rapid aging.

Metabolic Aging

As you go about your day, your cells are constantly turning food into energy, which produces byproducts—some of which can be harmful to the body. The process of metabolization, while essential, can cause progressive damage to cells, a phenomenon referred to as metabolic aging. 

Some experts believe that slowing down the metabolic process through practices such as calorie restriction may slow aging in humans.

The Aging Process

Our age-obsessed culture is consumed with "slowing down aging" and increasing longevity, but the basic truth of it all is that growing old is unavoidable. No matter what you do, your body will change in a number of key ways.

For example, by the time a person turns 20, lung tissues will begin to lose their elasticity, the muscles around the rib cage will start to deteriorate, and the overall lung function will gradually begin to diminish.

Similarly, the production of digestive enzymes will begin to slow as we age, which affects how nutrients are absorbed into the body and the types of food we can digest without difficulty.

Blood vessels also lose their flexibility as we age. In people who are sedentary and eat poor diets, the loss of elasticity paired with the accumulation of fatty deposits can lead to atherosclerosis ("hardening of the arteries").

As women approach menopause, vaginal fluids will decrease and sexual tissues will start to atrophy due to the loss of estrogen. In men, lean muscles will thin and sperm production will diminish due to decreases in testosterone levels.

How to Slow Aging

Aging cannot be avoided. With that said, there are several things you can do to mitigate the environmental factors that influence aging:

  • Eat well. Added sugar, salt, and saturated fat wreak havoc on the body, increasing the risk of hypertension, diabetes, and heart disease. To avoid these aging-related concerns, increase your intake of fruits, vegetables, whole grains, low-fat dairy, and lean meat and fish.
  • Read labels. If you buy packaged foods for convenience, check the label to ensure that you limit your sodium intake to under 1,500 milligrams (mg) per day, your sugar intake to around 25 mg per day, and your saturated fat intake to less than 10% of your daily calories.
  • Stop smoking. Quitting cigarettes improves circulation and blood pressure while drastically reducing your risk of cancer. Though it often takes multiple quit attempts to finally kick the habit, there are effective cessation aids that can help.
  • Exercise. Most adults do not meet the recommended exercise requirements for good health (roughly 30 minutes of moderate to strenuous exercise 5 days per week). Even so, 15 minutes of moderate activity per day can improve longevity compared to no exercise.
  • Socialize. Socialization keeps us psychologically engaged and may help influence longevity as well. Maintain good, healthy relationships with others. Stay connected to the ones you love, and make it a point to meet new people.
  • Get ample sleep. Chronic sleep deprivation is linked to poorer health and shorter life spans. By improving your sleep hygiene and getting around 7 to 8 hours of sleep per night, you may not only feel better but live longer.
  • Reduce stress. Chronic stress and anxiety can be damaging to your body as they trigger the release of an inflammatory stress hormone called cortisol. Learning to control stress with relaxation techniques and mind-body therapies may help alleviate the indirect inflammatory pressure placed on cells.

A Word From Verywell

The acceptance of aging is essential to your physical and emotional well-being. If you fixate on getting old, you are more likely to overcompensate by exercising too much or embarking on diets that may do more harm than good.

By accepting aging as a process over which you have some control, you can make healthy choices whether you are 25 or 75. It is never too late to start.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Mark Stibich, PhD
Mark Stibich, PhD, FIDSA, is a behavior change expert with experience helping individuals make lasting lifestyle improvements.