A new study suggests that the month in which a person is born may be linked to the risk of developing chronic diseases.
Researchers in Spain analyzed tens of thousands of individuals and identified significant patterns connecting birth months with later health conditions.
The research team mapped all twelve months of the year and compared them to the likelihood of developing twenty seven different chronic illnesses.
Their analysis revealed unexpected correlations in several areas.
The study included close to thirty thousand participants.
Among the findings men born in September showed almost three times the risk of thyroid problems compared with those born in January.
The researchers also discovered that babies born in August had nearly double the risk of developing asthma compared with those born in January or February.
Women born in July were found to have a twenty seven percent higher risk of hypertension and a forty percent higher risk of urinary incontinence.
Some months appeared to be more favorable for long term health.
Men born in June had a thirty four percent lower risk of depression and a twenty two percent lower risk of lower back pain.
Women born in June had a thirty three percent lower risk of migraines and a thirty five percent lower chance of menstrual problems.
Overall September was identified as the safest month for avoiding chronic diseases.
A separate study published in two thousand fifteen found that individuals born in May have low disease rate while those born in October had the highest.
Another research project several years earlier reported that birth month might influence many aspects of life from intelligence to life expectancy.
Scientists found that babies born in the spring were at higher risk for several conditions including asthma autism and even Alzheimer’s later in life.
The reason for these differences may lie in environmental factors that change throughout the year.
Sunlight exposure and vitamin D levels vary by season and this vitamin plays a key role in regulating thousands of genes involved in development and health.
Higher viral and bacterial activity during winter months may also contribute to increased illness risk.
The head of the research team noted that the month of birth may reflect different exposures to environmental factors such as sunlight temperature viruses and allergens all of which can significantly affect fetal development and long term health outcomes.