Some Like it Hot!
Thermal aging, skin aging induced by chronic heat, is an increasingly common complication not only for chefs, bakers and regular spin and hot-yoga enthusiasts; but for everyone living a modern lifestyle. Thermal aging, regardless of origin (hot rooms, stoves, bonfires, hair dryers, or infrared radiation) results in lax and saggy skin, chronic redness and uneven pigmentation. Let’s take a deep dive into the mechanisms behind each of these symptoms:
1. SKIN LAXITY:
Nobody wants this! I can guarantee it!
Science Spiel™: Heat induces a decrease in skin firmness (increase in laxity) due to diminished expression of procollagens and induction of matrix metalloproteinases 1 and 3 (MMP-1 and -3).
Beauty Spiel™: Your hot skin produces less collagen and destroys collagen faster. This perfect storm leaves your skin feeling and looking lax, as collagen is the most abundant skin component responsible for firmness.
2. SKIN SAGGINESS:
Really? First my skin is lax and now is saggy too??!! … My apologies for bearing bad news, but heat induces severe skin elasticity alterations.
Science Spiel™: Mechanistically speaking, heat triggers uneven expression of elastic fiber components and the deposit of elastotic material similar to those observed in solar elastosis (non-functional elastin). To further explain, elastic fibers are formed by tropoelastin (elastin) and by fibrillin-rich microfibrils. These components must be properly balanced to create functional elastic fibers. Thermal stress alters this balance resulting in loss of skin elasticity. In addition, chronic increase in skin temperature induces MMP-12, an enzyme that destroys elastic fibers.
Beauty Spiel™: Your hot skin produces elastic fibers that cannot stretch and recoil properly and destroys those fibers that can. The result is as simple and sad as saggy skin.
3. OXIDATIVE DAMAGE AND INFLAMMATION:
The ugly truth about thermal aging continues; on top of sagging and lax skin we have redness, uneven skin tone and increased sensitivity.
Science Spiel™: Thermal stress promotes oxidative stress and inflammation resulting in erythema, hyper-pigmentation and chronic destruction of skin components and cells. Heat-induced free radicals increase expression of MMPs perpetuating the destruction of collagen and elastin and promoting oxidative DNA damage. Heat-induced oxidative stress also consumes endogenous antioxidants such as glutathione, dehydrogenase 1 and heme oxygenase. Thermal aged skin is infiltrated by large number of mast cells and macrophages. These immune cells are responsible for chronic inflammation, increased blood flow and new angiogenesis.
Beauty Spiel™: Heat reprograms your skin into a self-destructive mood in which repair is prevented and damage is perpetuated.
Let’s face it, we all want an EVEN skin tone.
Science Spiel™: Melanocytes (melanin producing cells) become activated in response to skin injury. Persistent increases in temperature are major skin insults strongly stimulating uneven production of melanin or heat-induced melasma. Melanocyte activation also results in increase basal heat sensitivity as these cells form tight contact with cutaneous nerves. In addition, thermal stress activates epidermal TRPV1 receptors, triggering neuro-inflammation characterized by erythema, swelling, further temperature increase, tenderness, and pain.
Beauty Spiel™: Persistent exposure of your skin to heat triggers a vicious cycle of pain, sensitivity, tenderness and uneven skin darkening.
This is the story behind thermal aging. Most of the time, skin temperature increases are preventable - do we really need to do hot yoga at 40°C (104°F) for 90 min? If unavoidable, can we at least minimize heat exposure by externally cooling the skin? Thermal aging mitigation is as important as UV and pollution damage prevention. All three trigger premature aging and, in combination, may further accelerate and intensify skin damage.
It seems that we are losing the battle against aging, isn't it? Do not despair! We have several options. My favorite is VESS™ ANTIOXIDANTS, the best line of defense against heat and chronic inflammation. Previously, I created products using Dunaliella salina (IBR) and Vitis vinifera stem cell flower extract (Naolys), as these two potent antioxidant extracts prevent and neutralize chronic and acute inflammation, strongly inducing skin repair. Another of my favorite ingredients is Physialis angulata (Chemyunion) for its unique role in decreasing skin temperature and corticoid-like effects preventing inflammation.
FlawlessCanvas Fun Facts:
1. Normal skin temperature is between 31-36°C (88-97°F); as little as 15-20 minutes sun exposure may increase dermal temperature to 40°C (104°F).
2. Thirty minutes of heat exposure, three times per week is sufficient to alter skin function for up to six weeks.
3. One degree of skin temperature increase results in 10% increase in sebum secretion.
4. Dark skin types are more sensitive to heat-induced damage.