New research from University College London (UCL) provides another link between obesity and dementia risk. The study cites that in 2016, 38% of adults were considered overweight. Additionally, the global prevalence of dementia nearly tripled between 1975 and 2016. According to the study, current clinical guidelines consider obesity a "modifiable risk factor."
However, as UCL reports, different studies had conflicting results, some even suggesting that obesity could protect older adults from developing dementia. So, UCL researchers sought to clarify the relationship between obesity and dementia risk. This study's findings were published in the International Journal of Epidemiology in June of this year. Dr. Dorina Cadar, the senior author, told UCL, "These findings provide new evidence that obesity may have important implications in terms of dementia risk."
The study used a representative population sample of 6,582 English adults older than 50 years. As part of the English Longitudinal Study of Ageing, these participants were followed up with for 15 years. They were interviewed biannually and had interviews with a nurse every four years. All participants were free of dementia at their baseline assessment. According to UCL, doctor diagnosis, informant reports, and hospital episode statistics were used to determine dementia.
The study results showed a "positive and independent association between obesity and dementia risk." Participants with a BMI of 30 or higher at the beginning of the study had a 31% greater risk of developing dementia. Additionally, the study uncovered that women with abdominal obesity (using waist circumference as a guide) are nearly 40% more at risk of developing dementia than those with "normal" waist circumference measurements. Combining waist circumference and BMI, both male and female participants had a 28% higher risk of dementia than those in the normal range.
In the article from UCL regarding the study, Dr. Cadar said, "both BMI and waist circumference status should be monitored to avoid metabolic dysregulations." She suggests adopting a healthy and balanced diet, physical exercise, and lower alcohol consumption to reduce weight to optimal levels.
Paper co-author Professor Andrew Steptoe noted that rising obesity rates further compound the issue of dementia as a significant health challenge. He said, "by identifying factors that may raise dementia risk that are influenced by lifestyle factors, we hope that a substantial portion, but admittedly not all, of dementia cases, can be prevented through public health interventions."