According to researchers at the University of California, San Francisco (UCSF), and the San Francisco Veterans Administration Health Care System (SFVA), moisturized skin might prevent age-related ailments including Alzheimer's, heart disease and diabetes.
The cosmetic and personal care industry hears it all the time: the skin is the body’s largest organ; and we focus on its holistic status to treat signs of aging, or address compromised conditions. But what we do not often consider is how its negative health could affect our overall health—being the largest organ. A new pilot study from dermatologists at UCSF and the SFVA brings this perspective to light.
Inflammation, Aging and the Skin
According to the researches, as humans age, low levels of inflammation—or inflammaging—occur, driven by an increase in molecules in the blood known as cytokines. Such age-related inflammation has been linked to chronic diseases including Alzheimer’s, cardiovascular disease and diabetes. And while scientists suspected the inflammation stemmed from the immune system or liver, this group of dermatologists have a different theory.
“The inflammation must come from an organ big enough that very minor inflammation can affect the whole body," explained study senior author Mao-Qiang Man, M.D, a research scientist in the UCSF, based at the SFVA Health Care System, who is also a visiting professor at Southern Medical University in Guangzhou, China. "Skin is a good candidate for this because of its size.”
While ordinarily, cytokines help to repair defects in the barrier; but in aging skin, the barrier is not so easily repaired, and inflammatory signals continue to be released, eventually reaching the blood.
Man added that with aging, dermatological symptoms such as itchiness, dryness and changes in acidity arise. So while skin may have minor inflammation, due to its relative size to the body, this elevates circulating cytokine levels. Furthermore, skin starts to deteriorate at around the age of 50, with changes to epidermal pH, hydration and the permeability barrier; and a loss in moisture or breaks in the permeability barrier also can cause the skin to release inflammatory cytokines.
While ordinarily, cytokines help to repair defects in the barrier, in aging skin, the barrier is not so easily repaired, so the inflammatory signals continue to be released, eventually reaching the blood.
“Until recently, the scientific community didn’t believe that skin could contribute to systemic inflammation and disease," said study lead author Theodora Mauro, M.D, a professor of dermatology at UCSF and the SFVA Health Care System. "But in the last five years, studies of psoriasis and dermatitis have shown that skin inflammation from these diseases likely increases the risk of heart disease."
Based on these and other observations, the researchers published a study in the Journal of the European Academy of Dermatology and Venereology, whereby they attempted to reverse age-related skin damage using an over-the-counter skin cream formulated with cholesterol, free fatty acids and ceramides, which had previously been shown to contribute to skin repair.
Using the cream reportedly lowered participants’ cytokine levels to be nearly equivalent with people in their 30s.
Thirty-three older adults between the ages of 58 and 95 years applied the cream all over their bodies twice daily for 30 days. After one month, the researchers measured blood levels of three cytokines—interleukin-1 beta, interleukin-6, and tumor necrosis factor (TNF) alpha—all of which have been implicated in age-related inflammatory diseases.
Use of the cream reduced the amount of all three cytokines, compared with both the participants’ levels before application of the cream and the levels of similarly aged adults who did not use the cream. In fact, using the cream reportedly lowered participants’ cytokine levels to be nearly equivalent with people in their 30s.
“We're going to see whether using the cream to keep epidermal function normal as people age will prevent the development of those downstream diseases,” said co-author Peter Elias, M.D., a UCSF professor of dermatology based at the SFVA Health Care System. “If we do, the implication would be that after the age of 50, you would want to be applying an effective topical barrier repair preparation daily for the rest of your life.”