How moisturizing your skin reduces the risk of dementia

Want to cut your risk of dementia? Moisturize your skin, UCSF researchers say


Researchers at UC San Francisco announced this week that age-damaged skin in older adults may be contributing to a wide range of chronic, age-related conditions that include heart disease and Alzheimer’s disease.

Here’s what the dermatological researchers said they learned from their work with the San Francisco Veterans Administration Health System: As aging skin begins to break down, the immune system releases small proteins known as cytokines to signal that there’s inflammation in damaged areas of the skin. These tiny inflammatory cytokines can leak into the body’s circulation system, and if there are enough of them, they trigger body-wide inflammation. That triggers so called “inflamm-aging” among older adults.

“The inflammation must come from an organ big enough that very minor inflammation can affect the whole body. Skin is a good candidate for this because of its size,” Dr. Mao-Qiang Man, the study’s senior author. “Once we get old, we have dermatological symptoms like itchiness, dryness and changes in acidity. It could be that the skin has very minor inflammation, and because it’s such a large organ, it elevates circulating cytokine levels.”

Scientists have long questioned why there were so many inflammatory cytokines in the circulation system of older adults. Young people do not typically have as many. There are theories that they come from the lungs or from digestive system, Man said, but UCSF dermatologists felt certain that the culprit was the skin.

They devised an experiment to test out that hypothesis, asking one group of seniors to apply a specified amount of skin cream twice daily over 30 days. They also had groups of young people and seniors who did not use any of the lotion.

At the end of the experiment, they once again measured cytokine levels in all subjects, Man said, and the seniors who used the skin cream saw dramatic reductions in three cytokines that have been linked to age-related chronic diseases. The three were interleukin-1 beta, interleukin-6 and tumor necrosis factor.

Among adults who used the skin cream, cytokine levels fell nearly to the level of people in their 30s. The study participants, ages 58 to 95, also lowered their skin’s acidity, improved hydration and repaired its permeability.

Although the study had a small cohort of people, the scientists said, the findings are promising. Now, they say, they are hoping others can reproduce the results. Man and another researcher, Peter Elias, are consultants for the company that produced the skin cream used in the study.