High Blood Pressure and Impaired Brain Health: Investigating the Neuroprotective Potential of Magnesium

Abstract

High blood pressure (BP) is a significant contributor to the disease burden globally and is emerging as an important cause of morbidity and mortality in the young as well as the old. The well-established impact of high BP on neurodegeneration, cognitive impairment, and dementia is widely acknowledged. However, the influence of BP across its full range remains unclear. This review aims to explore in more detail the effects of BP levels on neurodegeneration, cognitive function, and dementia. Moreover, given the pressing need to identify strategies to reduce BP levels, particular attention is placed on reviewing the role of magnesium (Mg) in ageing and its capacity to lower BP levels, and therefore potentially promote brain health. Overall, the review aims to provide a comprehensive synthesis of the evidence linking BP, Mg and brain health. It is hoped that these insights will inform the development of cost-effective and scalable interventions to protect brain health in the ageing population.

Keywords: blood pressure; brain ageing; dementia; magnesium (Mg).

Figure 1

The figure shows the global rise in brain ageing cases and the increasing incidence of dementia, highlighting the urgent need for prevention. A major risk factor is high blood pressure (BP), which shares several common risk factors with brain ageing. High BP affects a significant portion of the population worldwide, with recent findings indicating an earlier onset of hypertension in younger individuals. Higher magnesium intake is associated with reduced BP and improved cardiovascular health. Additionally, the protective effects of magnesium extend to lowering the risk of cognitive decline and brain ageing.

Figure 2

Schematic overview of the relationship between blood pressure (BP), ageing mechanisms, brain changes, and cognitive function. It depicts how increased BP adversely affects endothelial function, leading to oxidative stress, inflammation, vascular atherosclerosis, and calcification, which may further elevate BP. Chronically high BP is associated with microscopic changes in the brain, including blood–brain barrier (BBB) disruption, microglia activation, pro-inflammatory responses, demyelination, and the accumulation of amyloid plaques and tau protein. These microscopic alterations result in macroscopic changes such as larger white matter lesions and reduced brain size, ultimately contributing to accelerated brain ageing and an increased risk of dementia.

Figure 3

Schematic overview illustrating the relationship between magnesium (Mg), ageing mechanisms, and micro- and macrostructural brain changes. It shows how higher dietary Mg intake supports vascular health by improving endothelial function and regulating blood pressure (BP). Mg also contributes to reducing inflammatory processes, thereby mitigating the harmful effects of chronic inflammation on brain tissue. Additionally, Mg exhibits neuroprotective properties, such as the ability to block NMDAR (N-methyl-D-aspartate receptors), which is involved in excitotoxicity—a process that can damage neurons during ageing. These beneficial effects of Mg lead to a reduction in various brain-ageing pathologies, including glial cell loss, microglia activation, oxidative stress, neuroinflammation, demyelination, amyloid accumulation, and tau phosphorylation. By counteracting these pathological mechanisms, Mg intake may help preserve brain health and slow down age-related brain degeneration, ultimately reducing the risk of cognitive decline.

Figure 4

Schematic overview of mechanisms mediating the neuroprotective effects of magnesium on brain ageing. The antihypertensive effect of magnesium may be linked to slower ageing, although recent research by Alateeq et al. [307] found no significant effects in a large population sample. Emerging evidence suggests that inflammation may partially mediate the association between magnesium intake and brain volume, indicating that the anti-inflammatory properties of magnesium could help reduce brain ageing. Furthermore, multiple pathways, such as NMDA receptor modulation, may play a role in the neuroprotective effects of magnesium. While evidence from human studies on NMDA modulation remains limited, further research is needed to fully elucidate these interconnected mechanisms.