MUSCAT—A growing number of experts are warning that Arab women—especially those who are pregnant—should increase their vitamin D levels through diet and sun exposure. Some scientists also say women need to consider vitamin supplements, but others strongly contest this, highlighting the supplements’ side effects.
“The prevalence of vitamin D deficiency across the Arab world is too high,” says Khitam Mohammad, a professor in the department of midwifery at the Jordan University of Science and Technology. Studies have consistently shown that more than 70 percent of Arab women are vitamin D deficient.
“Women are more likely to suffer from depression due to a lack of vitamin D because they’re [sometimes] more covered up,” says Alaa Badawi, a public-health consultant for Qatar’s Ministry of Health. “Many women here also prefer to maintain a fair skin tone. We need to talk about this in the Arab world.”
Additionally, a lack of vitamin D is associated with a number of diseases, including rickets in children and osteoporosis in adults, principally women. It is also linked to symptoms like fatigue, muscle weakness and hair loss.
The lack of sun exposure is not the only factor to blame for the high incidence of the vitamin deficiency. A diet lacking in the so-called “good fats” found in eggs, fish and milk is also a contributor, along with genetics.
Mohammad’s research paper, published in 2016, was one of the first attempts to study vitamin D deficiency in women who have recently given birth. She measured the vitamin D levels of 171 new mothers in Jordan and also asked them to fill out a questionnaire. She found that 76 percent of them were deficient and that the insufficiency correlated with lower education level, dress style, lower sun exposure, not taking multivitamins, and a darker skin tone. (Those women born with a darker skin tone have high melanin levels, which can lower vitamin D.)
“Vitamin D supplementation must be considered during pregnancy and lactation,” she concluded.
Mohammad’s results are consistent with what other researchers are finding.
At Sultan Qaboos University in Oman, Mohammed al-Buloshi, an associate researcher in the department of immunology and microbiology, is looking at factors that coincide with miscarriages and fertility problems. He says that women who experience more than one miscarriage are also more likely to be vitamin D deficient. “In some hospitals, they’ve introduced vitamin D supplements for pregnant women. We need to increase pregnant women’s vitamin D levels,” he says.
A 2010 study looked at 105 pregnant women in the United Arab Emirates and found that three quarters of them were severely deficient in vitamin D. The author of the paper suggested that Arab women should urgently try to get more sun exposure and take vitamin D supplements.
But this isn’t a stance shared by everyone.
“There has been an explosion of researchers in the region interested in studying vitamin D deficiency,” says Jumana Saleh, a professor in the department of biochemistry at Sultan Qaboos University.
“But there is so much controversy in saying that taking supplements would solve the problem,” she continues. “There are no studies to prove they actually improve health outcomes. Association does not prove causation.”
She says that a patient who is aware of her deficiency and has been told to take daily supplements may also be more likely to make diet changes and get more sun. This makes it hard to confidently say the supplements caused an improvement in vitamin levels, she argues.
In her own research, Saleh looked at vitamin D levels of more than 300 undergraduate female students at her university. She also found a high rate of deficiency. “But they don’t eat healthily and they aren’t often exposed to the sun. Here in the Gulf it’s so hot that we avoid the sun altogether.”
If the problem can be helped by eating better and sitting in the sun for short periods in the winter months, then there isn’t necessarily a need to introduce pills, says Saleh.
She is skeptical of the idea of supplements, especially in high doses. “Vitamins have many interactions with different minerals,” she says. For example, vitamin D in high doses can increase calcium in the blood, “and that’s not very good.”
The calcification that could result from high calcium levels can harden the blood vessels, which contributes to heart disease.
“I am myself vitamin D deficient, but will supplements prevent me from future diseases? That is far from proven,” says Saleh.
Despite her arguments, it’s a scientific debate that is likely to continue, both in the Arab region and elsewhere. Clinicians may find it easier to recommend a daily pill instead of telling people to get more sun and change their diet. Researchers may find it hard to definitively prove the connections between vitamin D deficiencies and negative physiological effects.