Strange Ways Your Birth Month Can Affect Your Health

Have you ever wondered what your birth month says about you? If the month in which you celebrate your birthday has anything to do with who you are or why you are the way you are? The month in which you were born correlates to a lot about you — and we're not talking about astrology-type stuff. (Although, if you're into horoscopes, you'll be happy to know they're actually great for your mental health!)

There's proven science behind the ways in which your birth month can affect your health. In fact, according to a study published by JAMIA, your birth month can be connected to different diseases you may develop throughout your life. The research discovered 55 diseases that are significantly dependent on the month in which you were born. And, as it turns out, your birth month correlates to more than just diseases. It can affect your physical and your mental health in a lot of interesting ways.

Want to learn more? Take a look through the various ways that the month in which you were born may or may not impact your health.

Think about all of your super athletic friends. What do they all have in common? How many of them were born in the fall? If it's at least a few of them, that could be because of science. Autumn babies tend to be the most athletically inclined people around, according to a study published in the International Journal of Sports Medicine. "There is a clear physical advantage for those born in the autumn and this may explain some of the bias in sports selection attributed to the relative age effect, particularly when the British school-year (September) cut-off is used," the researchers write. 

Specifically, those born in November tend to be "fitter and more powerful" than those who are born at other times throughout the year — particularly the summer months of April, May, and June. And those born in October are stronger than everyone else except for those born in September and November. So the next time you have to pick a partner for a game or a team for a sporting event, it may be wise to ask people about their birthdays first!

People born in the warmer months aren't just summer lovers. Nope, spring and summer babies are also generally healthier than those who are born throughout the rest of the year. If you were born in the spring or summer, chances are that you have a decreased risk for things like heart disease and common medical problems. According to research published in Columbia Magazine, people born in May have the lowest risk of developing diseases. Meanwhile, those born in October and November have the highest risk of disease. The study compared the birth dates and medical histories of 1.7 million patients who were treated at both New York-Presbyterian Hospital and Columbia University Medical Center between the years 1985 and 2013. 

Warmer-month babies are generally healthier perhaps because of the vitamin D they were exposed to in their infancy, according to the research. Though there may be other factors involved. More research needs to be done to tell. If you find yourself low on vitamin D, consider supplementing with food such as salmon, egg yolks, or canned tuna.

Fall and winter babies are at a greater risk of developing diseases than those born in the spring and summer. And, yet, they seem to live a lot longer than everyone else. That's right: as revealed by research published in Columbia Magazine, those born in the winter are at a greater risk of atrial fibrillation, hypertension, congestive heart failure, cardiomyopathy, and more. Nevertheless, according to research published by the University of Chicago in the Journal of Aging Research, people born during this time of year are more likely to live to celebrate their 100th birthday than anyone else. 

"It was found that months of birth have significant long-lasting effect on survival to age 100," according to the research. "Siblings born in September [to] November have higher odds to become centenarians compared to siblings born in March. A similar month-of-birth pattern was found for centenarian spouses. These results support the idea of early-life programming of human aging and longevity."

Your mother's Vitamin D exposure could be a key reason why you are the way you are — or, rather, why your health is the way your health is. According to research published in Columbia Magazine, babies born in October and November have the highest risk of developing diseases, while spring and summer babies tend to be better protected from diseases — and this may have to do with what mothers were exposed to while they were pregnant. "It's not horoscopes or the alignment of planets," John Perry, a senior investigator scientist at the University of Cambridge, said, according to US News.

"Many disease-dependent mechanisms exist relating disease-risk to birth month," according to a study published by JAMIA. For example, evidence links a type of asthma to birth month because individuals born in seasons with more dust mites have a 40 percent increased risk of developing asthma complicated by dust mite allergies. Later, researchers discovered that sensitization to allergens during infancy actually boosts one's lifetime risk of allergies. Plus, some neurological conditions may be associated with birth month because of vitamin D exposure.

Ever hear about the "Winter Blues," or "Blue Monday"? It's also known as seasonal depression, and it's a very real thing that affects a lot of people. The colder months are just so... cold and dark, with no sunshine to give you that vitamin D boost we all deserve. It makes perfect sense that the frightful weather outside would take a toll on many people's mental health. It also makes sense that people who are born in the winter months would be at a higher risk of season depression, according to Time.

"Buckle up, babies, things could get rough," Time writes. "Among the challenges facing people with winter birthdates are higher levels of schizophrenia, bipolar disorder, SAD and depression. That's a nasty handful, but there are a few compensations: winter babies are less irritable than those born in fall." So you might be more depressed, but you also might be less irritable. So at least that's something, winter kids.

How tall are you? While you might have been told old wives' tales about your height all these years, you might just be taller or shorter because of the month in which you were born. Yup. All that milk you drank and all that stretching you did might have helped you grow taller, but your height might just come down to the time of year you were born.

People who were born during the summertime tend to be taller, according to science. A study published in Heliyon found that summer babies are typically taller than winter babies because of what they were exposed to in their infancy. According to the research, "whilst other mechanisms may contribute to these associations, these findings are consistent with a possible role of in utero vitamin D exposure." So you can blame your mom for her lack of vitamin D exposure for crushing your pro basketball star dreams (or you can thank her if you did end up with some height!).

Ever feel like you just can't wake up? Or, on the contrary, do you have a too-good internal clock? You know the kind that wakes you up at 6 am on a Saturday morning just because you know that, when the sun rises, it's time for you to get up for work, too — except it's the weekend. If you fall into the latter category of people, perhaps it's because your birthday falls in the spring or summer. According to a study published by Vanderbilt University, people who were born in the warmer months have better internal clocks than people who were born in the cooler months.

"Our biological clocks measure the day length and change our behavior according to the seasons," writes the study's author, Professor of Biological Sciences Douglas McMahon. "We were curious to see if light signals could shape the development of the biological clock ... It's important to emphasize that, even though this sounds a bit like astrology, it is not: It's seasonal biology!"

Mood swings are real. You might be feeling great in one breath and, in the next, you may feel like your world is collapsing. While it's normal to have days and moments of overjoy and days and moments of lower vibrations, some mood swings can be tied to various mental health disorders, according to Healthline. This includes bipolar disorder, major depressive disorder, personality disorders, and more. And summer babies tend to be moodier than winter babies, according to research published by the European College of Neuropsychopharmacology.

Lead researcher, Assistant Professor Xenia Gonda, claims: "Biochemical studies have shown that the season in which you are born has an influence on certain monoamine neurotransmitters, such as dopamine and serotonin, which is detectable even in adult life. This led us to believe that birth season may have a longer-lasting effect." They studied over 400 subjects and, indeed, discovered that the month in which they were each born increased or decreased their chances of developing different mood disorders.

The sad reality is that someone dies every 36 seconds in the United States from cardiovascular disease, according to the Centers for Disease Control and Prevention. That means that about one in four, or 655,000 Americans, die from heart disease every single year. It costs the country about $219 billion each year, too. In other words: It's serious stuff. And for women born in the spring and summer, there's a "slight but significant increase in cardiovascular disease specific mortality" compared to those born at other times during the year, according to a study published in The BMJ. 

The study looked at 43,248 deaths, including 8,360 cardiovascular disease-related deaths. While the researchers did not find a significant association between birth month, birth season, and overall mortality, they did find that women born between March and July were worse off than those born in November. Those who were born in April had the highest cardiovascular disease mortality.

Eating disorders may be more common than you think. In fact, they affect at least nine percent of the population around the world and nine percent of the United States population, or about 28.8 million Americans, will have an eating disorder at some point throughout their lifetimes, according to ANAD. 

People born in the springtime are linked to more eating disorders, as well, according to a study published in the British Journal of Psychiatry. As the study writes, "susceptibility to anorexia nervosa is significantly influenced by the season of birth, with higher rates in those individuals born in the spring and lower ones in those born in the autumn." Eight out of every 100 people born between March and June had anorexia, compared to just seven percent of those without — a 15 percent risk increase.

"The idea is that there is some sort of risk factor that varies seasonally with anorexia," study researcher Lahiru Handunnetthi said, according to LiveScience. While the "excess of spring births" could be the culprit, factors like seasonal changes in temperature, sunlight exposure, and vitamin D levels could play roles, too.

Food allergies are quite common. After all, there are a lot of possible food allergies to have and/or develop over time. Research estimates that over 32 million Americans have food allergies, though some, of course, are much worse than others, according to Food Allergy Research and Education. Some people may just develop hives and an itchy tongue. Others, however, may have difficulty breathing or their throats could tighten up. And for some, a very severe food allergy, called anaphylaxis, could cause sudden death. Every year in the United States, 200,000 people are in need of emergency medical care in response to allergic reactions to food.

Fall babies have a higher risk of developing food allergies, according to a study published in the Journal of Epidemiology and Community Health (via LiveScience). Specifically, babies born in the fall have a 9.5 percent risk of developing food allergies, which compares to the 5 percent risk for babies born in June and July. Those born in November and December are also three times more likely to deal with wheezing and eczema.

How good is your eyesight? If you're nearsighted, it might have something to do with the month in which you were born. Summer babies tend to have more eyesight issues than people born in other months of the year, according to a study of 300,000 young adults published by Tel Aviv University. According to the research, babies born in June and July have a 24 percent greater risk of developing severe myopia than those who are born in December and January.

Myopia, which is also known as nearsightedness or shortsightedness, is "a common vision condition in which you can see objects near to you clearly, but objects farther away are blurry," according to Mayo Clinic. "It occurs when the shape of your eye causes light rays to bend (refract) incorrectly, focusing images in front of your retina instead of on your retina."

Schizophrenia is a severe mental disorder in which people may experience "hallucinations, delusions, and extremely disordered thinking and behavior that impairs daily functioning," according to Mayo Clinic. It requires "lifelong treatment" to control symptoms since schizophrenia can indeed be disabling. And spring birth months are linked to schizophrenia, according to a study published in The American Journal of Psychiatry.

"The odds for having been born during the winter-spring months were slightly higher among both siblings and patients in all birth-year groups," writes the research. "Seasonal variation of births among patients with schizophrenia may consist of two factors: 1) parental procreational habits causing a slight excess of births of both patients and unaffected siblings during the winter-spring months and 2) irregular environmental factors that considerably increase the magnitude of the seasonal variation of births among patients but not their siblings."

Type 1 diabetes is increasing around the world. About 15 per 100,000 people have it, and the global prevalence is 9.5%, according to a study published in the journal Health Promotion Perspectives. If you have it, your pancreas doesn't make insulin or it "makes very little insulin," which is a hormone that helps blood sugar enter your cells for energy, according to the Centers for Disease Control and Prevention. High blood sugar can be dangerous and can cause a lot of different symptoms, both physically and mentally.

People born in the spring tend to have Type 1 diabetes more so than people born in other seasons. According to a study published by the American Diabetes Association, spring births are linked to an increased likelihood of type 1 diabetes, though that is not necessarily true in all regions across the country.