Sun Exposure

Sun exposure induces chronic inflammation. This type of inflammation is a destructive process that leads to abnormal cellular function and weakens skin’s immunity, specifically the immunity that helps skin repair itself (reduced Langerhans cells). Sun exposure will weaken skin’s ability to repair damaged DNA. With repeated sun exposure, more damaged DNA-mutated cells appear (pre-cancerous cells that will eventually cause skin cancer). Sun exposure will also disturb many cellular functions and normal skin texture, resulting in: • Discoloration due to abnormally functioning melanocytes or their mutations (melanoma or lentigo maligna) • Dryness and roughness due to increased transepidermal water loss and the appearance of hard keratin due to the abnormal functioning of keratinocytes • Sensitivity and redness as skin becomes photosensitive due to inflammation induced by sun and disruption of skin barrier function, initiating a negative body response, creating abnormal blood vessels (telangiectasia) and redness • Damaged skin collagen and elastin from repeated sun exposure, which will be apparent later in life as leathery skin texture and accelerated skin aging (earlier and deeper wrinkles and folds)

Factors Impacting Skin Damage Sun Exposure Before Age 20 Before age 20, the skin is rich with vitality due to proper and active cellular function and repair. The earliest sun-damaging effect seen in this group is the appearance of freckles in light-skinned individuals. This freckling is an indicator of early photosensivity and susceptibility to severe sun damage later in life (due to unstable and false melanin, known as pheomelanin) that can affect skin texture and lead to a high possibility of skin cancer. Individuals who tan well may have less chance of skin cancer in the future as tanning represents the presence of strong natural resistance (due to stable, real melanin, also known as eumelanin). However, they will suffer from severe textural damage, resulting in skin with a leathery feel and solar elastosis. It should be clear that no one escapes sun damage if their skin is not protected at an early age. This is true even in individuals who tan well, as tanned skin is essentially skin that is screaming “help.”

Sun Exposure After Age 20 After age 20, sun damage is manifested by skin dullness, discoloration and roughness. In the 30s and 40s, it is characterized by the appearance of actinic keratosis and lentigines. During the 50s, full-blown textural damage and precancerous lesions are evident, as is the appearance of skin cancer in some. Skin Type Fair skin will have more damage than darker skin; thin skin will show earlier sun damage signs compared to thick skin. Presence of Disease Skin diseases that cause inflammation (acne, rosacea) can increase susceptibility to sun damage.

Immunological Diseases and Certain Genetic Disorders Certain diseases and genetic disorders (lupus, xeroderma pigmentosum) can increase photosensitivity, accelerate the appearance of sun damage and result in skin cancer. Location Sun-damaging effects are stronger near water, snow or at high altitudes. Medications Some blood pressure medications, antidepressants, Isotretinoin and Tetracycline are among the many medications that can induce photosensitivity.

I would recommend the Zo Skinhealth Sunscreen or the OC Facial Center Daily Moisture with SPF50