College graduates often find themselves earning more money and having a better quality of life than their less-educated counterparts, but a recent study suggests a potential health consequence of higher education. According to the observational study, higher levels of education are linked to increased risk of developing certain types of brain tumors. While education level is more closely associated with one's socioeconomic background than are genetics, it is interesting just how much of an influence a college education can have on one’s overall health.

For the study, which is now published online in the journal BMJ, researchers looked at information on 4.3 million Swedish residents born between 1911 and 1961 who had developed a brain tumor in 1991. The patients were monitored between 1993 and 2010 to see if they developed a primary brain tumor and information on their educational attainment, disposable income, marital status, and occupation was also included in the review.

A number of trends became clear from the review. For example, the researchers noted that men who had attended higher education for at least three years were 19 percent more likely to develop a specific type of brain tumor, called a glioma, than men who did not receive education past that mandated by the state. The trend was even stronger in women, and higher education was associated with a 23 percent increased risk for glioma and a 16 percent increase for meningiomas, another type of brain tumor. These trends still persisted even when the researchers took other factors into account, such as the individuals’ levels of disposable income and marital status.

Although meningiomas, which occur in the meninges, the tissues that surround and protect the brain and spinal cord, are mostly non-cancerous, gliomas can be dangerous. Glioma is a term used to describe any type of tumor that occurs in the supportive tissue of the brain known as the glia. According to the American Brain Tumor Association, the glia help keep neurons in place and functioning properly.

One external factor that did seem to contribute to an individual’s brain tumor risk was occupation. Men with professional and managerial roles were 20 percent more likely to develop gliomas than men with manual jobs. Glioma risk was 26 percent higher for women with professional and managerial roles, compared to women working manual labor jobs.

The researchers are not entirely clear why the association exists, but co-study author Dr. Amal Khanolkar told Medical Daily that they have some hypotheses.

“We feel the most likely explanation is that people in higher socioeconomic positions are more likely to seek care at an earlier stage of the disease process and therefore are more likely to be registered in the cancer registry,” said Khanolkar, although she could not account for the differences between the genders.

Aside from this newfound association between college educations and brain tumors, higher education is most often associated with better health, The Huffington Post reported. Although, in America it has become common for couples to marry those with a similar education level to them, this practice has done little to change the overall genetics of the U.S. population. Still, despite education having little influence on your genetics, it still has a large hold on your overall health.

A 2012 study published in the American Journal of Public Health found that earning a bachelor's’ degree is linked with fewer symptoms of depression and higher self-reported overall health. In addition, according to the Robert Wood Johnson Foundation, the United States' largest philanthropic organization focused solely on health, educated individuals also live longer and healthier lives.

The findings are off-putting, but the researchers emphasize that it is far too early to draw conclusions that certain lifestyle choices, such as education and profession, really contribute to brain tumor risk. However, they are enough to suggest the topic be covered more closely.

“We will further investigate ethnic differences in brain tumour incidence as well as analyses socioeconomic and ethnic differences in survival from brain tumour,” concluded Khanolkar.

Source: Khanolkar AR, Ljung R, Talback M, et al. Socioeconomic position and the risk of brain tumour: a Swedish national population-based cohort study. BMJ . 2016