Why summer is the Gulf's SAD season

ABU DHABI // Scientists and psychologists have long pinpointed Vitamin D deficiency as a reason why colder temperatures and shorter days lead to "winter blues" in other parts of the world.

But in the UAE, the condition may exist in reverse, a research team from Zayed University has found. Residents of the Emirates may be prone to an inverted variety of Seasonal Affective Disorder (SAD) after being trapped indoors due to the intolerable heat of the summer months.

And those who wore sun cream, abayas or khandouras during the summer blocked still further what little Vitamin D their bodies could absorb, making them more depressed, according to researchers.

The study by a team from Zayed University and the Institute of Laboratory Medicine at Sheikh Khalifa Medical City - published last month in the International Journal of Mental Health Promotion — is one of the first in the region to link the change in seasons in the Gulf climate with depressive symptoms and Vitamin D deficiency.

The benefits of Vitamin D have been widely touted by a growing body of medical experts who suggest that sunlight helps prevent osteoporosis and depression, as well as certain forms of cancer, such as breast cancer.

The study, funded by the Emirates Foundation, closely monitored any shift in mood among 197 female undergraduate students over two-week periods in October and March. Participants completed individual questionnaires, and submitted blood samples to test their Vitamin D levels.

The research found that depressive symptoms and decreasing levels of the vitamin were far more prevalent in samples taken in October, following the end of summer.

The participants were all Emirati, but the results are expected to shed light on possible cases of reversed SAD among all UAE residents.

Research from a previous study at the university found no difference in the change in levels of depression between men and women.

While there was a link between depressive symptoms and decreasing levels of Vitamin D, it was not yet possible to determine conclusively the exact nature of the relationship, said Dr Justin Thomas, a professor of psychology at Zayed University. Dr Thomas, who was involved in the research, is also a columnist for The National.

The key questions, he said, were whether depression caused Vitamin D deficiency, whether decreasing levels of the vitamin caused mood shifts, or whether a third factor causes both.

"As people withdraw from the sun and outdoors during the hottest months of the year, they become isolated, which can give rise to feelings of depression," he said.

The cycle of depressive symptoms and Vitamin D deficiency was broken during the cooler winter months, when residents are able to participate in "sun-enhanced behavioural activation", he said.

The next step for researchers would be to test for whether depression abates when subjects are supplemented with different dosages of Vitamin D. Determining the dosage can be difficult, as people who are older, obese or have darker skin have more difficulty absorbing the vitamin.

The only vitamin that the body synthesises itself, Vitamin D is largely created by the action of ultraviolet rays on the skin, and is difficult to obtain from sources other than the sun. The vitamin is naturally present in very few foods.

While supplements are available in many pharmacies, Dr Thomas said the recommended dosage of 400 international units (IUs) is too low to have any influence. Other studies have used as much as tens of thousands of IUs to determine whether the vitamin has any effects.

"The problem is that most people are deficient in this vitamin — it is abnormal to have the right amount, even based on international guidelines," he said.

Dr Amber Haque, an associate professor of psychology at United Arab Emirates University, said that it was normal to feel helpless and depressed in the summer months.

"Just like the 'winter blues', the lack of outdoor activity and maybe exposure to the sun could have effects on the mind," he said.

"When we are not engaged in any activity, life becomes boring, and we begin to think deeply about things, whether they are positive or negative. We may become hooked on television, computers or eating, continuing the cycle of depression."

econroy@thenational.ae