Study: Greater Body Fat Is a Risk Factor for Reduced Memory Ability and Thinking

Even after taking cardiovascular risks or vascular brain injury into account, the association remained, study results show.

The results of a new study show that greater body fat is a risk factor for reduced cognitive function, such as processing speed, in adults.1

Even after taking cardiovascular risks or vascular brain injury into account, the association between body fat and lower cognitive scores remained. This suggests that other pathways could be linked to excess body fat to reduced cognitive function.1

In the study, 9166 participants were measured by bioelectrical impedance analysis to assess their total body fat, and 6733 underwent magnetic resonance imaging (MRI) to measure abdominal fat packed around the organs, known as visceral fat, and the MRI also assessed vascular brain injury, which is when areas in the brain are affected by reduced blood flow to the brain.1

The results were published in JAMA Network Open.1

“Preserving cognitive function is one of the best ways to prevent dementia in old age. This study suggests that one of the ways that good nutrition and physical activity prevent dementia may be by maintaining healthy weight and body fat percentage,” co-author Eric Smith, MD, a neurologist and associate professor of clinical neurosciences at the University of Calgary in Canada, said in a statement.1

Participants in the study ranged in age from 30 to 75 years, with an average age of about 58 years. All lived in Canada or Poland. Approximately 56% were women. The majority were of white European origin, with about 16% from other ethnic backgrounds.1

Individuals with known cardiovascular disease were excluded.1

Smith is head of the brain core lab for the 2 population cohorts used for this new analysis: the Canadian Alliance for Healthy Hearts and Minds (CAHHM) and PURE Mind, which is a sub-study of the large, international Prospective Urban Rural Epidemiological (PURE) study.1

The CAHHM study was funded by the Canadian Partnership Against Cancer, Heart, and Stroke Foundation of Canada, and the Canadian Institutes of Health Research (CIHR). The PURE-Mind study was funded from multiple sources including the Population Health Research Institute, CIHR, and the Heart and Stroke Foundation.1

The obesity prevalence in the United States between 2017 and 2018 was approximately 42.4%, up by about 11.9% between 1999 and 2000, according to the CDC.2

During the same time, the prevalence of severe obesity increased to about 9.2% from 4.7%, according to the CDC.2

In addition to cognitive functions, obesity is commonly related to certain types of cancer, heart disease, stroke, and type 2 diabetes.2

Additionally, the obesity prevalence among adults aged 20 to 39 years-old was approximately 40%; aged 40 to 59 years, approximately 44.8%; and aged 60 years and older, about 42.8%.2

Non-Hispanic Black adults had the highest prevalence of obesity, at 49.6%, Hispanic adults had a 44.8% prevalence, non-Hispanic white adults had a 42.2% prevalence, and non-Hispanic Asian adults had a 17.4% prevalence.2

Reference

1. Greater body fat a risk factor for reduced thinking and memory ability. EurekAlert. News release. February 1, 2022. Accessed February 2, 2022. https://www.eurekalert.org/news-releases/942034

2. Overweight & obesity: adult obesity facts. CDC. Updated September 30, 2021. Accessed February 2, 2022. https://www.cdc.gov/obesity/data/adult.html