Background: Gliomas, particularly high-grade gliomas such as glioblastoma, represent a major challenge due to their poor prognosis. While dietary factors have been proposed as potential modulators of glioma risk, causal inference has been hindered by confounding and reverse causality in observational studies. This study employs Mendelian randomization to investigate the causal relationship between dietary factors and glioma risk. Methods: A two-sample MR framework was applied, utilizing genome-wide association study data for 22 dietary exposures and glioma risks, including both GBM and non-GBM subtypes. Instrumental variables (genetic variants) were identified for each dietary factor to address confounding and pleiotropy. Causal inference was conducted using inverse-variance weighted regression, complemented by MR-Egger and MR-PRESSO analyses to assess and correct for potential pleiotropy. Results: A positive causal association was observed between the intake of cooked vegetables and the GBM risk (OR = 6.55, 95% CI: 1.86–23.12, p = 0.00350). While alcohol intake demonstrated a protective effect for non-GBM risk (OR = 0.770, 95% CI: 0.61–0.97, p = 0.029), beer was substantially linked to an increased risk of non-GBM gliomas (OR = 4.82, 95% CI: 1.84–12.59, p = 0.0014). Other dietary factors did not exhibit significant causal associations. Conclusions: These findings suggest that certain dietary factors, including cooked vegetable intake, beer consumption, and alcohol intake, may exert a causal influence on glioma risk. This study provides new insights into the potential dietary determinants of glioma and underscores the need for further investigation into modifiable risk factors for glioma prevention.

The human brain exhibits pronounced regional specialization in cellular composition, gene expression, and tissue organization. Increasing evidence indicates that these spatial differences influence where brain tumors arise and how they evolve. Across tumor entities such as gliomas, meningiomas, and brain metastases, specific molecular subtypes frequently display characteristic anatomical distributions, suggesting a functional coupling between tumor genetics and regional brain microenvironments. In this mini review, we summarize recent advances in understanding how regional brain biology shapes the molecular and ecological landscapes of brain tumors. We discuss evidence linking anatomical location with tumor genotype, cellular states, and microenvironmental interactions. We further highlight the emerging concept of “region-aware oncology,” in which tumor behavior is interpreted within the anatomical and molecular context of the surrounding brain tissue. A deeper understanding of this spatial coupling may improve tumor classification and support the development of region-informed diagnostic and therapeutic strategies.