New research has unveiled a significant connection between high Body Mass Index (BMI) and an increased risk of vascular-related dementia. Conducted by scientists from the University of Bristol, this study utilized a statistical method known as Mendelian Randomisation to analyze population data from the UK and other regions worldwide. The findings align with prior beliefs that a higher BMI correlates with a greater risk of developing vascular-related dementia, but they also highlight a critical factor: high blood pressure.
Dr. Liv Tybjærg Nordestgaard, the study’s first author, began this project in Copenhagen before extending her work at the University of Bristol. She stated, “Dementia is a devastating disease that currently affects 50 million individuals worldwide. Unfortunately, treatment and prevention options are scarce.” The research suggests that addressing both high BMI and hypertension could significantly reduce the risk of cognitive decline associated with vascular dementia.
Vascular dementia, which results from reduced blood flow to the brain, is estimated to affect approximately 180,000 people in the UK, according to the NHS. Symptoms of this condition typically worsen over time, although there are strategies that can help slow its progression.
The recent study contributes to an expanding body of research indicating that certain lifestyle changes may prevent dementia. For instance, a 2024 report from The Lancet Commission revealed that about 45% of dementia cases could potentially be delayed or reduced by addressing fourteen key risk factors. These include high LDL cholesterol, diabetes, hypertension, smoking, excessive alcohol consumption, and obesity, among others.
Wendy Weidner, Director of Research and Publications at Alzheimer’s Disease International, emphasized the importance of a comprehensive approach to risk reduction. “This study underscores the critical importance of a life-course approach to risk reduction, with targeted interventions across different stages of life,” she noted. Weidner added that early identification and management of these risk factors, particularly in lower-resource settings, could substantially lessen the global impact of dementia.
While high BMI is often used as a measure of health, its effectiveness is sometimes questioned. The NHS points out that BMI does not account for factors such as muscle mass, bone density, age, sex, ethnicity, and fluid retention. For individuals with high muscle mass, for example, BMI may inaccurately categorize them as overweight or obese, despite a low body fat percentage.
To calculate BMI, individuals can use a calculator available on the NHS website. Nonetheless, it is not suitable for everyone, particularly those under 18, pregnant individuals, or those with certain medical conditions. The NHS further notes, “A higher BMI increases the chance of developing long-term conditions, such as type 2 diabetes and heart disease.”
As researchers continue to explore the connections between lifestyle factors and dementia risk, the hope is that increased awareness and proactive measures can lead to better outcomes for individuals at risk. Each step towards addressing these challenges holds the potential to create significant personal and societal benefits in the fight against dementia.
