Vitamin D insufficiency is associated with higher asthma risk, according to a new research presented at this week’s meeting of the American Public Health Association in Denver. Because vitamin D decreases levels of inflammation, it can improve the body’s response to drugs involved in asthma treatment, as a researcher told Live Science.
Asthma makes it difficult to breathe given that it causes inflammation and a narrowing of the airways. People at higher risk are those with low levels of Vitamin D, which is contained in mushrooms, oily fish, fortified cereals, egg yolks, red meat, and tofu, among other foods.
Yueh-Ying Han, a research assistant professor of pulmonary medicine, allergy and immunology at the University of Pittsburgh School of Medicine, told Live Science that asthma patients are not advised to take vitamin D as an attempt to replace their current asthma treatment. She noted that people with vitamin D insufficiency should take vitamin D supplements, which are relatively safe.
The research team collected data from more than 9,700 children aged 6 to 17, and 25,000 adults between the ages of 18 and 79, who had been part of a yearly national health survey conducted in the United States between 2001 and 2010. The study participants were asked whether they had been diagnosed with the disease or experienced wheezing in the past year. They were also tested to determine the level of vitamin D contained in their blood.
Once they analyzed the information, the researchers discovered that 70 percent of the adults and 68 percent of the children had vitamin D insufficiency, meaning that they had a level lower than 30 nanograms per milliliter. Nearly 2,000 adults and 1,200 children had received an asthma diagnosis in the past year.
Additionally, the scientists found that kids with vitamin D insufficiency were 1.35 times at higher risk of developing asthma than those who had the right levels of vitamin D in their blood. As for adults with low levels of vitamin D, they were more likely to report wheezing in the past year than those with adequate levels but they were not at a higher risk for an asthma diagnosis.
The findings of this paper confirm a review study published in September that found that risk of asthma attacks in adults and children was reduced in those who took vitamin D supplements. However, the supplements did not help improve daily symptoms of the disease.
The researchers also discovered that the prevalence of asthma decreased from 8.2 percent in 2007-2008 to 7.4 percent in 2009-2010. Between 2001 and 2010, the portion of people with too low vitamin D levels dropped from three-quarters of participants to two-thirds of participants.
Vitamin D insufficiency could also be linked to bladder cancer
A separate team of researchers in the U.K. found that a diet deficient in vitamin D increases the risk of bladder cancer as it prevents an immune response to abnormal cells, according to a report by the Daily Mail. They discovered that one in five adults have vitamin D insufficiency and that three in five have low levels.
The British scientists, who presented their findings at the Society for Endocrinology annual conference in Brighton, analyzed seven previous studies about the disease and vitamin D insufficiency. Five studies revealed that low levels were linked to a higher risk of bladder cancer.
Because people need to be exposed to sunlight to get all of the vitamin, the researchers noted that it is hard to maintain adequate levels during the winter. The scientists studied the transitional epithelial cells, which activate and respond to vitamin D so it can trigger an immune response.
In July, Public Health England advised people to take supplements in the winter to ensure they have the right level of the vitamin, which is ten micrograms per day. It added that breastfed babies and young children must consume a supplement to boost their intake of the sunlight vitamin.
Study lead author Dr. Rosemary Bland, from the University of Warwick, said that further research was needed to confirm the association between bladder cancer and vitamin D insufficiency.
“But our work suggests that low levels of vitamin D in the blood may prevent the cells within the bladder from stimulating an adequate response to abnormal cells,” she pointed out, as quoted by the Daily Mail.
Dr. Bland added that vitamin D could be easily used to prevent cancer as it is cheap and safe. In 2013, there were over 10,000 new cases of bladder cancer across the United Kingdom. According to Cancer Research UK, 5,300 died from the disease. And in 2015, about 76,000 adults from the U.S. were diagnosed with the form of the disease, which took the lives of 15,000.
Source: Live Science