Aging and the Integumentary System – Understanding the Changes That Happen To Our Skin

Aging is a natural process that no one can escape. All changes in the body begin to go through some subtle and some not-so-subtle changes as a person starts to age. The same is the case with the integumentary system of the body which comprises of the skin, hair, nails, and glands. Being the largest organ of the body, the skin perhaps undergoes the most amount of visible changes as we age. Changes in the skin are amongst some of the most visible signs of aging. Here we look at the process of aging, the integumentary system, and understanding the changes that happen to our skin.

The skin is the largest organ of the body and an integral part of the integumentary system, which also includes the nails, hair, and glands. The main function of the skin is to provide protection to the body. It serves as a barrier against pathogens and injuries, ultraviolet (UV) radiation from the sun, loss of bodily fluids, wound healing, and even the stress of other mechanical forces. The skin also plays a crucial role in regulating our body temperature and is also involved in the production of vitamin D when exposed to the UV light of the sun.^{(1, 2, 3, 4)}

It is common knowledge that our skin remains at the mercy of many external forces as we age, including harsh weather, pollution, sun, and bad personal habits. How your skin ages depend on many factors like your lifestyle, diet, your genes, and personal habits like smoking or alcohol use.

The skin is made up of three major layers. The outer-most thinner layer is known as the epidermis, which forms the main line of defense for our body. This is our protective barrier. Under this, there is a thicker inner layer, or the middle part known as the dermis, which contains skin cells, capillaries, hair follicles, nerves, and the oil glands. The third and innermost layer located under the dermis is known as the subcutaneous layer, and it contains some hair follicles, blood vessels, sweat glands, and fat. Each layer of the skin contains connective tissue with collagen and elastin fibers that lend support to the skin, and also provide strength and flexibility.^(5, 6, 7)

As you age, the layers of the skin start to adhere less tightly and the tissues start to get thinner. This makes the skin feel looser and it is more likely to wrinkle. With aging, the epidermis starts to thin out, even though there is no change in the number of cells that are present in this outermost layer of the skin. However, there is a decrease in the number of pigment-containing cells known as melanocytes. The melanocytes that are left over, start to increase in size. As you age, your skin starts to look thinner, more translucent (clear), and thinner. You may even witness the appearance of pigmented spots like age spots or liver spots that start to appear on the areas that are exposed to the skin. These areas are known as lentigos.^(8, 9, 10)

Changes also take place in the connective tissues of the skin, which decrease the strength and elasticity of the skin. This is known as elastosis and again, this impact is more noticeable in the areas that are exposed to the sun. Elastosis leads to a leathery or weather-beaten appearance that is most commonly seen in farmers, sailors, or anybody who spends a long time working outdoors.⁽¹¹⁾

Apart from these changes, the blood vessels present in the dermis layer also become more fragile, which causes easy bruising, conditions like cherry angiomas, bleeding under the skin known as senile purpura, and other such conditions.^(12, 13)

At the same time, another change that occurs in the subcutaneous fat layer is that it begins to thin which leads to lesser insulation and padding. This also increases the risk of getting skin injuries while decreasing the ability to maintain body temperature. Since with the thinning of the subcutaneous fat layer you have less natural insulation, you can easily get hypothermia if you are not careful in cold weather.

There are also certain medications that get absorbed by the fat layer. Thinning or shrinkage of this layer of the skin sometimes impacts the manner in which these medicines work, changing their effectiveness.

Aging also has an effect on the sweat glands, which are another integral part of the integumentary system. The sweat glands start to produce less sweat as you age, making it difficult to keep cool. This increases the risk of getting heat strokes or overheating.

Another common pattern you would have observed in many older people is the occurrence of growths like warts, skin tags, brown rough patches, and other such blemishes.

Another common development on the skin as an effect of aging is the appearance of pinkish rough patches. This is something you need to watch out for as there is a small chance of these patches turning into skin cancer.

As you continue to age, the risk of getting a skin injury goes up. Since the skin becomes more fragile, thinner, and you end up losing some of the protective fat layers of the skin, you become more prone to getting injured and less capable of sensing pressure, heat, cold, vibration, and touch.

It is important to remember that pulling or rubbing on the skin as you get older can easily cause skin tears and the blood vessels can break more easily. This is why you are  more likely to notice bruises, raised collections of blood known as hematomas, or flat build-ups of blood known as purpura developing easily after getting even a small or minor injury.

The skin changes can also cause pressure ulcers to develop. This happens due to reduced activity with age, loss of the fat layer, and other illnesses. You will also begin to notice sores more easily, especially on the outer surface of the forearms.

Aging skin will take longer to heal and repair itself. You may notice that wound healing is now nearly four times slower. Conditions like diabetes, lowered immunity, changes in the blood vessels, and other factors are also going to affect healing.

Since skin changes due to aging are often times related to sun exposure, it is important to follow certain preventive measures. You should try to prevent sunburn as much as possible and always make use of a good quality sunscreen when you step outside, even in the winter. Always wear protective clothing and a wide-brimmed hat when going out in the sun. At the same time, good nutrition and drinking plenty of fluids can help ward off or delay many of the changes that start appearing on the skin as you age.

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