🧠 Obesity and high blood pressure directly cause dementia

Weight problems and high blood pressure are not just warning signals but direct triggers of dementia. A new study has just confirmed this.

Published in The Journal of Clinical Endocrinology & Metabolism, this research is based on the analysis of genetic and medical data from large cohorts in Denmark and the United Kingdom. To establish cause-and-effect links, beyond mere correlations, the scientists adopted a methodological approach called Mendelian randomization.


The results clearly indicate that a high body mass index directly contributes to the risk of dementia. Furthermore, high blood pressure appears to be an important explanatory mechanism for this relationship, highlighting the importance of monitoring these two parameters.

These discoveries open up concrete avenues for prevention. Acting on weight and blood pressure before the appearance of cognitive symptoms could thus reduce the likelihood of developing dementia, particularly in its vascular forms. Although weight-loss medications have not shown effectiveness once the disease is established, early intervention could change the game.

How obesity and high blood pressure affect the brain

Excess weight and high blood pressure can damage the blood vessels in the brain. This phenomenon reduces the supply of oxygen and nutrients, which can lead to progressive brain damage and cognitive decline.

High blood pressure, in particular, exerts constant pressure on the arteries, promoting inflammation and oxidative stress. These processes impair neuron function and accelerate degeneration related to forms of dementia like vascular dementia.

Furthermore, obesity is often associated with metabolic imbalances, such as insulin resistance, which can also harm brain health. These multiple interactions explain why controlling these factors is important for preserving mental abilities.

Mendelian randomization in practice

This statistical method uses inherited genetic variations to mimic randomized trials. By exploiting the randomness of genetic transmission, it makes it possible to establish causal links between a factor, such as obesity, and a disease, such as dementia, without the biases of observational studies.

Its application in this study confirmed that obesity and high blood pressure are direct causes, and not just risk factors. This strengthens the credibility of the observations and guides future public health research.

Despite its advantages, Mendelian randomization has certain limitations, such as the need for well-identified genetic variants. Nevertheless, it is an interesting tool for exploring the mechanisms underlying multifactorial diseases.