Over the years, science has responded to astrology by building up a series of studies that helps explain the relationship between a person’s month of birth and their susceptibility to different health conditions.
Naturally, a baby’s development begins in the womb, and the conditions they are exposed to play a huge role in their development. Maternal nutrition, in particular nutritional deficiencies, can greatly affect a child’s health and immunity.
Seasonal viruses can also impact fetal development, so a baby that develops during wintertime may be vulnerable to more early developmental setbacks than a baby that develops through the summer.
A 2015 Columbia University study, the largest of its kind to date, came up with a huge amount of statistics to bolster the speculation that month of birth really does impact health.
The study compared the birth dates and medical histories of 1.7 million patients against a grand total of 1,688 diseases. The patients’ records were gathered from New York-Presbyterian Hospital and Columbia University Medical Center (CUMC) and were dated between 1985 and 2013.
CUMC researchers discovered that 55 of the 1,688 diseases did, in fact, correlate with the season of birth. The reason? The time of year that a baby is born dictates many of the environmental factors that baby is exposed to during gestation, birth, and early development.
It is possible to ascertain the relevance of these findings, and other studies, to our individual seasons of birth by breaking the findings down.
A University of California study from 2001 used Austrian and Danish patient records. They discovered that patients born in March, April, May, and June had a higher risk of heart disease. They also had shorter life spans.
This was reflected in the CUMC study’s findings. Columbia researchers found that people born in the United States in March faced the highest risk of nine different variants of heart disease including atrial fibrillation, congestive heart failure, and mitral valve disorder.
Links to vitamin deficiencies as a result of developing in the womb during the winter months gesture toward a causal explanation.
Ken Ong of the University of Cambridge, England, published a study in the journal Heliyon. Ong and his colleagues looked at 450,000 U.K. birth records from U.K. Biobank dated between 1946 and 1975 of people aged 40 to 69.
“Children who were born in the summer were slightly heavier at birth, taller as adults, and went through puberty slightly later, relative to those born in winter months,” Ong explained.
Babies weighing more at birth, researchers found, experience delayed puberty. This in turn led to improved health outcomes for those people in adult life.
The U.K. Institute for Fiscal Studies added to the conversation by positing that children born in August are 30 percent more likely than children born in September to be labeled as “problem” students by their teachers. As the youngest children in their class, they have trouble keeping up with their peers.
The CUMC study discovered that individuals born in the fall were best protected against cardiovascular diseases.
Conversely, their vitamin D levels were lower and parathyroid hormone levels higher during the winter, without supplements. High levels of parathyroid hormone correlate with increased heart failure in elderly males, the study advised.
Babies born approximately four months before the “winter virus peak,” said the American Journal of Respiratory and Critical Care Medicine, carry a high risk of developing asthma. However, the same study explained that prevention of winter viral infection during early infancy could prevent asthma from occurring altogether.
The CUMC data suggested that around 1 in 675 occurrences of ADHD could relate to being born in New York in November. This result correlates with a Swedish study, referenced in the Journal of the American Medical Informatics Association, also showing peak rates of ADHD occurring in November babies.
Winter babies were also at a higher risk than their peers of developing neurological problems, according to the results of the CUMC study.
Because December babies are born during peak cold and flu season, the American Journal of Respiratory and Critical Care Medicine also advises that they could be more susceptible to asthma and allergies. Contracting a winter infection in the first four months of life could be particularly dangerous for babies born in this month.
Do We Need Preventative Measures?
“Lifetime disease risk is affected by birth month,” CUMC researchers concluded. “Seasonally dependent early developmental mechanisms may play a role in increasing lifetime risk of disease.”
However, the study’s authors added, it is important not to become overly anxious about the correlations between birth month and disease risk. There are significant associations, but the “overall disease risk,” they maintained, is “not that great.”
“The risk related to birth month is relatively minor when compared to more influential variables like diet and exercise,” said the CUMC study’s lead author Dr. Nicholas Tatonetti, speaking to The Huffington Post.
“The most exciting aspect of our research is that it may open up new research opportunities into what the exact environmental exposures are that lead to increased risk of certain diseases,” Tatonetti added. “Once we have those mechanisms, then we may be able to make lifestyle and diet recommendations.”
The next step for researchers is to expand their studies into other locations with other environmental factors around the world, enabling them to extrapolate data and make the fascinating findings relevant for everybody.