Scientists divide skin Ageing into two categories — intrinsic and extrinsic ageing in our skin structure. Intrinsic Ageing includes the age-related changes that you cannot control. These originate predominantly in genetic factors and unfold over time at a predetermined pace. Extrinsic Ageing, on the other hand, is caused by factors that you can control. As you will learn throughout this book, you can do numerous things to avoid or even reverse the damage wrought by extrinsic Ageing.
What is Intrinsic Ageing
When you think of intrinsic Ageing, think heredity. The processes of intrinsic Ageing are the same for each individual, but your genetic legacy dictates the rate at which they unfold. The way your parents’ skin aged will give you good clues to how your own skin will age. If one or both of your parents enjoyed youthful skin to an advanced age, you may well be fortunate enough to have inherited the same characteristics.
One of the most dramatic changes in a woman’s appearance takes place in the years surrounding menopause. The drop in estrogen levels associated with menopause is well known to weaken the bones and increase a woman’s risk of contracting osteoporosis. However, reduced estrogen affects the health of the skin as well, causing a substantial loss of collagen, an important protein that makes up most of the skin’s supportive structure. The result is the proliferation of wrinkles and sagging skin often seen in postmenopausal women.
Although the visible signs of Ageing are apparent in the furrows, sags, and wrinkles of an older face, the processes of Ageing actually originate at a microscopic level, i.e., on the level of each individual cell. Skin Ageing is the result of a cumulative loss of numerous functions at the cellular level, which decreases the cells’ capacity to perform the metabolic and regenerating activities that uphold the health of the skin.
What is Extrinsic Ageing
Extrinsic Ageing is a far more powerful factor in the Ageing process than the time-related decay in biological functions associated with intrinsic Ageing. Fortunately, most of the factors that induce extrinsic Ageing are largely avoidable.
Excessive Sun Exposure
Of all the influences that cause premature Ageing, no single one is as important as sunlight. In our time and age, damage caused by excessive exposure to the sun is without a doubt the leading cause of skin Ageing. In fact, researchers estimate that skin damage induced by the ultraviolet rays of the sun is responsible for up to 8o percent of the skin’s Ageing.
One of the main reasons that sunlight is so harmful to the skin is that ultraviolet (UV) radiation triggers free radicals production in the skin. Free radicals are molecules that are missing an electron and hence are in a state of chemical disequilibrium. To restore their balance, they turn into little molecular-sized “Pacmans,” gobbling up electrons from surrounding molecules and, in the process, wreaking havoc at the cellular level of the body.
Free radical damage is serious business. Excess free radical production is thought to increase the risk of numerous chronic diseases, including such leading killers as heart disease, stroke, and cancer. When free radicals are produced in excess in the skin, they attack the collagen in the skin, causing it to lose its resilience and strength and accelerating the appearance of wrinkles.
Most of the sun damage that induces premature Ageing typically happens in the early part of our lives, but the results don’t show up until years later. For many people, early-life sun damage is a ticking time bomb that is set off once they enter their late thirties or forties. Fortunately, as we see in later chapters, there are many ways not only to protect yourself against further sun damage, but to actually reverse the damage the sun might already have wrought on your skin.
The term “smoker’s face” was coined to characterize the maze of creases, crinkles, and deep grooves, and the dull, lifeless complexion one often sees on the faces of longtime smokers. If you don’t care that much about how you age, go ahead — smoke to your heart’s content! Apart from spending long hours in the sun, there is no better way to make sure your skin ages prematurely.
The list of the ways in which smoking affects the skin is long, but it can be summed up in one word: choking. Smoking decreases the flow of oxygen to the skin by as much as 3o percent. Cigarette smoke causes the fine blood vessels in the dermis to constrict, cutting off the nutrient supply the skin needs for constant self-regeneration and blocking the removal of waste products. As a result, the skin’s natural functions are compromised, and the skin begins to look gray and dull.
Smoking also triggers free radical production in the body, upsetting the delicate balance of bodily tissues and organs and causing similar damage to the skin as UV radiation. In fact, the combination of excessive sun exposure and smoking is a deadly cocktail for your skin and a surefire way to induce premature Ageing.
Airborne toxic waste products affect the skin in much the same way as cigarette smoke. Air pollutants restrict the flow of oxygen and nutrients to the skin and, in addition, trigger excess free radical production. Free radicals are always present in the body; they are a byproduct of normal metabolic activity, and the body has a series of built-in mechanisms for neutralizing them before they go on a rampage in the cellular environment. However, external influences, such as sunlight, smoke, and industrial pollution, can tip the balance of free radicals in the body and cause them to increase beyond the body’s capacity to inactivate them.
The effect of free radical damage on the skin and how to counteract it is one of the newest and most exciting areas of research in dermatology today. When it comes to manageing the Ageing process, understanding free radicals and how to neutralize them is a key step. In later chapters, we show you how to control or even reverse free radical damage.
Wear and Tear
Wear and tear is another source of extrinsic Ageing. The expression lines that emerge when you smile, frown, or lift your eyebrows create a constant mechanical challenge to the skin tissue in those areas. Over time, this shows up in your face as smile lines around your mouth and eyes, vertical furrows between your brows, or horizontal lines on your forehead. Similarly, if you sleep on your side with your face against a pillow year after year, the pressure of the skin against the pillow will cause creases that eventually become permanent. Such lines are less likely to emerge if you sleep on your back.
Your skin can also be damaged if you are exposed to excessive heat or cold. If you live in a place where the winters are harsh and cold, your skin will be challenged not only by the cold temperature, but also by the dry air common during the winter. In addition, people who spend a lot of time around the heat emitted from furnaces, stoves, or ovens, such as bakers or cooks, often suffer from premature ageing of the skin.
Excessive use of harsh soaps, detergent-based cleansers, or cosmetic products that are too strong for your skin is another source of extrinsic Ageing. Such products may cause irritation or inflammation of the top layer of the skin, damageing it and accelerating its deterioration.
Numerous elements of your daily routine exert a powerful influence on the appearance of your skin, including your eating habits, how much alcohol you consume, how much sleep you get, the degree of stress to which you are exposed, and the amount and type of exercise you engage in. Poor lifestyle habits affect the whole body and, as a consequence the skin as well, where they typically show up as a dull, sallow, uneven, and prematurely wrinkled complexion.
Healthy habits, on the other hand, can increase your well-being, prevent the onset of disease, and slow the progression of Ageing in your body as well as your skin. In later chapters, you learn how to introduce some simple daily behaviors that have the potential to do more for your skin than almost anything else you can do.