- Abnormal eating habits can develop more skin cancer cells, due to a disruption in the skin's biological clock
- Individuals who eat late at night are more vulnerable to sunburn that can cause long-term effects like skin aging and skin cancer
- The UV-damaged skin can be repaired with a protective enzyme called Xeroderma pigmentosum group A (XPA)
Eating at abnormal times disrupts the biological clock of the skin, which includes the daytime potency of an enzyme. This enzyme helps in protecting against the sun's harmful ultraviolet radiation, reveals a new study from the O'Donnell Brain Institute and UC Irvine.
Dr. Joseph S. Takahashi, Chairman of Neuroscience at UT Southwestern Medical Center's Peter O'Donnell Jr. Brain Institute said that the finding of this study indicates that people who eat late at night are more vulnerable to sunburn and long-term effects like skin aging and skin cancer are seen, and there is a need for further research.
‘Sunbathers should avoid midnight snacks before being exposed to UV rays, as it can cause longer-term effects such as skin aging and skin cancer.’
How well the skin is protected from the sun's harmful UV rays depends on the feeding schedules, reveals the study. Eating at abnormal intervals disrupts the skin's circadian rhythms, and weakens the daytime potency of a protective enzyme.
Dr. Takahashi, also an Investigator with the Howard Hughes Medical Institute said, "This finding is surprising. I did not think the skin was paying attention to when we are eating."
The mice which were given food only during the day at an abnormal eating time for the otherwise nocturnal animals were found to sustain more skin damage, when exposed to ultraviolet B (UVB) light during the day than during the night.
Abnormal Eating Habits Cause Harmful Shift in Skin Clock
Xeroderma pigmentosum group A (XPA), an enzyme that repairs UV-damaged skin, shifts its daily cycle to be less active in the day.
The XPA cycles were not altered in mice who were fed only during their usual evening times and were found to be less susceptible to daytime UV rays.
Dr. Takahashi, holder of the Loyd B. Sands Distinguished Chair in Neuroscience said that having a normal eating schedule, will protect individuals better from UV during the daytime and if you have an abnormal eating schedule could cause a harmful shift in the skin clock, like it happened in the mouse.
In previous studies, strong roles for the body's circadian rhythms in skin biology have been demonstrated. But, little is understood as to what controls the skin's daily clock.
The research study published in Cell Reports
documents the vital role of feeding times, which is a factor that scientists focused on, as it has already been known to affect the daily cycles of metabolic organs like the liver.
In this study, it was found that besides disrupting XPA cycles, the expression of about 10 percent of the skin's genes is affected with the changing eating schedules.
Dr. Bogi Andersen of University of California, Irvine, who led the collaborative study with Dr. Takahashi said that to better understand the association between eating patterns and UV damage in people, especially how the XPA cycles are affected more research is required.
"It's hard to translate these findings to humans at this point, but it's fascinating to me that the skin would be sensitive to the timing of food intake," said Dr. Andersen, Professor of Biological Chemistry.
Dr. Takahashi is researching other ways in which eating schedules affect the biological clock. He is noted for his landmark discovery of the Clock gene
, which aids in regulating circadian rhythms.
In an earlier study, the time of day the food is eaten is more important to lose weight than the amount of calories ingested. A long-term research is being conducted to measure how feeding affects aging and longevity, said Dr.Takahashi.
The UV study has been supported by the Irving Weinstein Foundation, the National Institutes of Health, the National Science Foundation Graduate Research Fellowship and the China Scholarship Council.
"This is surprising. I did not think the skin was paying attention to when we are eating," said Dr. Joseph Takahashi, UT Southwestern.
What is Skin Cancer?
Skin cancer is a disease where malignant cells are found in the epidermis, which is the outer layer of the skin. Skin cancers can develop due to a continuous exposure to sun over the years.
Sunburn and Ultra Violet light exposure cause maximum damage resulting in DNA damage to the skin. The body can usually repair this damage before gene mutations occur. But when a person's body cannot repair the damaged DNA, then it results in skin cancer. It is likely that most skin damage from ultraviolet radiation occurs before the age of 20.
The regular use of sunlamps and sunbeds increases the risk of developing skin cancer. Some of the areas of skin that have been badly burned, or have had long-term inflammation have an increased risk of squamous cell carcinoma.
- Hong Wang, et al. Time-Restricted Feeding Shifts the Skin Circadian Clock and Alters UVB-Induced DNA Damage. Cell Reports(2017).DOI:10.1016/j.celrep.2017.07.022