what are the top three causes of dry, dehydrated skin?

Intrinsic Aging
Intrinsic aging is the normal process of physical change over time that’s more about genetics than lifestyle. (Lifestyle-induced aging is known as premature aging.) Activity of the sebaceous glands responsible for oil secretions tend to decrease with age, and the skin’s natural hydrators decline over the years. Aging also may cause blood flow to the skin to decrease, causing a drop in sebum production.

Weather / Environmental Elements
Prolonged exposure to the sun causes water to evaporate from skin, which is why sunburnt skin requires more moisturization than unexposed areas. Likewise, cold winds, air conditioning units, forced air heating and low temperatures can also dry out skin, contributing to premature aging.

Lifestyle
The trend of fat-free diets can deprive our bodies of skin-friendly Essential Fatty Acids (EFAs). This deficiency can result in chronic itching, dryness, scaling, thinning and can lead to an imbalance in prostaglandins (chemical messengers that do many things, such as control inflammation). Excess intake of alcoholic beverages and certain medications (such as nasal decongestants) can also contribute to dry skin.

Immunogenic Inflammation
Triggered by the immune system, skin inflammation is caused by a foreign substance such as pollen or artificial fragrances.

Neurogenic Inflammation
Triggered by the nervous system, sensitized or inflamed skin may be the result of the environment, chemicals or physical and emotional stress.

Both immunogenic and neurogenic inflammation can yield the same redness, itching and swelling that result when the body is injured or irritated. In the end, it is the combination of genetic susceptibility, immune disruption, nerve activity and epidermal barrier function that contributes to skin sensitivity and inflammation.

Loss of Protective Barrier
Excess exfoliation, exposure to soap and water, even psychological stress can compromise the skin’s protective barrier, lowering tolerance against potential stressors resulting in sensitization and irritation.

Causes of Hyperpigmentation: UV Exposure
In addition to the development of an overall tan, exposure to UV light may also stimulate hyperpigmentation in specific spots on the hands, face and neck. These dark spots are often referred to as age spots or liver spots (lentigines), usually become evident in our early forties, and become increasingly more evident as we age. By the time we reach 60 years old, 90% of all individuals will have sun-induced age spots, known as lentigines.

These spots, more than anything else, give away a person’s age. Age spots are caused by skin’s continued exposure to the sun over many years, and unlike freckles, they do not fade in winter. (Freckles, also known as ephilides, are flat spots that are red or brown, typically appear during the summer months and fade in winter. They are most often found in individuals with fair skin and are generally a genetic trait.)

Causes of Hyperpigmentation: Post-Inflammatory Hyperpigmentation
In addition to genetics and environmental influences, skin pigmentation is effected by endocrine (hormonal) factors, usage of prescription drugs, stress, topically-applied products including cosmetics, and wound healing to the skin tissue. The latter incidence gives rise to post-inflammatory hyperpigmentation (PIH), a phenomenon that is more problematic for individuals with darker skin color. PIH stems from the melanocytes exaggerated response to injury, however slight, which results in an increased or abnormal distribution of melanin in the tissues.

Causes of Hyperpigmentation: Melasma
Hormonally induced pigmentation manifests itself in various forms, such as hyperpigmentation spots and melasma, better known as the mask of pregnancy. Melasma affects primarily women of child-bearing age. Some studies suggest that up to 75% of women may develop melasma during pregnancy and about 33% of women on birth control pills also complain of this problem. It is more prevalent in women with darker skin color and it is most commonly seen in areas that are exposed to sunlight.

Some scientists say UV exposure seems to be a requirement for melasma to develop, which may account for the fact that it is less noticeable in winter months when UV exposure is lower. The most common pattern for melisma is centrofacial: on the chin, upper lip, cheeks, nose, and forehead. To a lesser extent, melasma is seen on the cheeks and nose, or on the jawline.

The condition may persist up to 5 years after pregnancy or stopping of birth control pills. Unfortunately, once melasma manifests in skin, chances of having it again increase.

Reactive Oxygen Species (ROS) are dangerous forms of oxygen molecules generated by UV rays and pollution. They attack and react with stable molecules within skin cells, causing irreversible damage to the cell, triggering wrinkles and lessening skin’s natural ability to repair itself. They form as a natural by- product of the normal metabolism of oxygen.

During times of environmental stress, ROS levels can increase dramatically, causing significant damage to cell structures. This is known as oxidative stress, which is the major cause of degenerative disorders including aging and disease. Studies have shown that UV-induced damage to the skin is in part caused by Reactive Oxygen Species. Lipid peroxidation also results from ROS damage to cell membranes, leading to premature aging, skin cancer and cell death.

Matrix Metalloproteinases (MMPs) are enzymes activated by UV exposure or inflammation. They contribute to the breakdown of existing collagen while inhibiting the formation of new collagen.

The formation of MMPs may be stimulated by internal growth factors and inflammatory modulators, as well as exposure to UV radiation. Within hours of UV exposure, the MMP genes are activated, resulting in the biosynthesis of collagenase and other MMPs. Because collagenase degrades existing collagen and inhibits the formation of new collagen, long-term elevation results in disorganization and clumping of skin cells – key characteristics of photoaged skin.

Advanced Glycation End-products (AGEs) The same glucose that provides energy for our cells can react with proteins (such as collagen), resulting in the formation of Advanced Glycation End-products (AGEs), which lead to wrinkles, inflammation, inhibited skin cell growth and accelerated aging. Why is this so important? Because we now know that inflammation is the catalyst critical to the aging process and many diseases. For example, diabetics have characteristically high levels of sugar in their blood and suffer from numerous health issues (including cataracts, atherosclerosis, etc.), which emanate from the formation of AGEs in the body. This is not restricted to diabetes; muscle weakness, heart disease and many diseases of the brain are associated with glycation. Scientists now believe that reducing glycation is a means of slowing the aging process and disease formation.

While stress creates the trigger for acne, there are four main factors that contribute to the development of acne: overactive sebaceous glands (the production of too much oil), dead skin cell accumulation, bacteria and inflammation.

When overactive sebaceous glands produce too much oil, this oil spills onto the skin’s surface, creating a slick, greasy appearance. This excess oil acts as a binder, holding on to dead skin cells that were meant to be shed. The follicle becomes clogged with a mixture of oil and dead skin cells, prohibiting oxygen from entering. This creates the perfect breeding ground for bacteria, which leads to the swelling, redness and inflammation around the follicle, resulting in acne.

To successfully treat, clear and prevent acne, the cascade of events leading to acne development must be controlled: we must regulate the sebaceous glands, promote exfoliation to help shed dead skin cells from the surface, kill bacteria and soothe inflammation.