Obesity, Physical Activity Level May Influence Brain Tumor Risk

overweight man
overweight man
Researchers found an association between obesity and meningioma risk, but not for glioma.

An elevated body mass index (BMI) has been linked to the development of several chronic, degenerative conditions, including diabetes, Alzheimer’s disease, and coronary heart disease. Now, new research indicates that obesity may also be linked to a greater risk of a lethal brain tumor, meningioma.

In a meta-analysis, researchers from the University of Regensburg in Germany explored the relationship between adiposity and physical activity and meningioma and glioma risk. The rate of occurrence for the two types of tumors are relatively the same, but gliomas have a worse prognosis. Currently, nearly no modifiable risk factors have been identified for the tumors, with any known risk factors unchangeable.

In total, 12 studies on BMI and six studies on physical activity were included in the analysis, which involved 2,982 cases of meningioma and 3,057 cases of glioma. Using normal weight as the reference group (BMI < 25), researchers found that people who were overweight (BMI = 25 to 29.9) were 21% more likely to develop meningioma (summary relative risk [RR] = 1.21, 95% confidence interval [CI] = 1.01–1.43) and those who were obese (BMI ≥30) were 54% more likely to develop meningioma (RR = 1.54, 95% CI = 1.32–1.79); however the factors were not found to be associated with glioma risk. There was a statistically significant positive association between BMI and meningioma, but not glioma.

There was a modest inverse relationship between high vs. low physical activity levels and meningioma (RR = 0.73, 95% CI = 0.61–0.88) and a weak inverse association with glioma (RR = 0.86, 95% CI = 0.76–0.97). Patients with the highest level of physical activity were 27% less likely to develop meningioma compared to those with the lowest level of activity.

“Given the high prevalence of obesity and the unfavorable prognosis for this type of tumor, these findings may be relevant for strategies aimed at reducing the risk of meningioma,” researcher Gundula Behrens, PhD, said.

While the study did show an association between weight and tumor risk, the researchers emphasized that tumors, especially meningiomas and gliomas, are rare, and that more research needs to be conducted in order to better understand the relationship between the two factors.


  1. Niedermaier T et al. Neurology. 2015; doi:10.1212/WNL.0000000000002020.