A recent report in the Annals of Allergy, Asthma and Immunology has implicated latitude as a major factor in the development of allergic asthma.
By using satellite analysis of ozone, which indicates the intensity of UV-B rays, scientists have drawn a correlation between latitude and allergies, showing that those living closer to the equator are at higher risk of having the ailment.
"UV-B rays exposure is higher for people living in areas closer to the equator," study lead author Vicka Oktaria said in a news release from the American College of Allergy, Asthma and Immunology (ACAAI). "This increase in UV-B may be linked to vitamin D, which is thought to modify the immune system. These modifications can lead to an elevated risk of developing allergy and asthma."
The current study strongly implicates the role that vitamin D has in the immune system and that an overabundance in the body can lead to allergies. Vitamin D is produced within the body after exposure to UV-B rays and is important in the proper functioning of the body. Ample vitamin D prevents Rickets, a disease known to cause softening and weakening of the bones.
As we have seen recently in China, air pollution has raised the incidence of asthma by over 40%, but this is the first time that UV exposure was linked to asthma incidence. Although the study found a correlation between the two, it did not directly show that the amount of UV-B exposure causes asthma and allergies.
"Allergies and asthma are serious diseases that can be life-threatening if not diagnosed and treated properly," Dr. Richard Weber, president of the ACAAI, said in the news release. "Both conditions can be more than bothersome for people, no matter their geographic location, and can last year-round."