The month of your birth can affect which diseases will afflict you. Seasonal changes in ultraviolet rays, vitamin D levels and viruses, more common in the winter, may affect foetal development, experts believe. Spanish scientists mapped birth months to 27 chronic diseases to see if it made a difference to long-term health and were surprised to find it has a significant impact for some conditions. Men who were born in September, for example, were almost 3 times more likely to suffer thyroid problems than those born in January.

August male babies had almost double the risk of asthma compared to those born at the beginning of year. Similarly, women born in July were 27% more likely to be diagnosed with high blood pressure and were at a 40% increased risk of incontinence. The University of Alicante, which carried out the study on nearly 30,000 people, also found that some months had beneficial effects on health.

What else did they find?

Men born in June were 34% less likely to suffer depression and 22% less likely to be diagnosed with lower back pain. Women born in June had a 33% lower risk of migraines and a 35% less chance of experiencing menopause problems. On the whole, September babies appeared to have least chance of being diagnosed with any chronic disease. This month, as well as October, is known to be when most babies are born, suggesting they are conceived around Christmas.

 Why is there a difference between months?

The researchers speculate that seasonal illness could be behind the variance, by either boosting the body’s inner defences or harming them early on. While sunlight triggers production of vitamin D in the body and lack of this in the first months of life may have long-lasting effects on mental and physical health. The ‘sunshine vitamin’ is known to help regulate thousands of genes during development and a wealth of research backs up its long-lasting influence on health.

‘A significant association.’

 Professor Jose Antonio Quesada, the study’s lead author, told ‘In this study we have evidenced a significant association between the month of birth and the occurrence of various chronic diseases and long-term health problems. 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. The differentiation of patterns by sex found that there may be a different vulnerability in men and women to these early exposure factors.’ The new findings were published in the journal Medicina Clinica.

Rate this