People often attribute everything from their personalities to love lives (or lack of) and wealth to their zodiac sign, but a new study says birth month can actually affect your health.

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The Daily Mail reports that some health professionals believe season changes in ultraviolet rays, vitamin D and viruses can actually impact fetal development. Researchers at the University of Alicante in Spain studied 30,000 people and found that chronic diseases and long-term health were linked to birth month.

Among their findings is that males born in September have triple the chances of developing thyroid problems than guys born in January. Baby boys born in August were twice as likely as developing asthma as those who were born early in the year. Men with June birthdays were more than one third as likely to be diagnosed with depression, but their chances of having lower back pain was about 22 percent less. Women in June, however, had about one third decreased odds of getting migraines and developed menopausal issues 35 percent less.

September babies were the healthiest overall and had the lowest chances of developing a chronic disease. So what causes these variations? While it’s not entirely clear why this happens, The Daily Mail reports scientists believe that seasonal illnesses could either help or harm your immune system early on. Researchers also theorize that those born in warmer seasons get a healthy dose of sunlight, which helps your body to produce vitamin D. The thinking is that nutrient levels at this early stage can have long-term effects on your health.

Study co-author Professor Jose Antonio Quesada said in The Daily Mail, ‘‘The month of birth may behave as an indicator of periods of early exposure to various factors, such as exposure to ultraviolet rays, vitamin D, temperature, seasonal exposure to viruses and allergies which may affect the development of the uterus and neonate in their first months of life.” Not only that but the team’s findings indicate that this impacts the genders in different ways.

“The differentiation of patterns by sex found that there may be a different vulnerability in men and women to these early exposure factors,” he said.

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Astrology fans likely aren’t surprised by this news as the zodiac has long associated with health. According to Tarot.com, certain areas of the body are ruled by specific signs. Libras, for example, are connected to the kidneys, skin, back and butt areas.

However, this study has been met with a hearty dose of skepticism from some in the scientific community. Dr Robert Cuffe, ambassador for the Royal Statistical Society, told The Independent, “Astrology has never made for great science.” He said that there are many patterns that appear to be amazing but doesn’t believe there is scientific backing for it.

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