The Study
Association of Obesity With Cognitive Decline in Black and White Americans
This study watched a lot of people over many years and noticed that those who were obese tended to start with lower brain scores but didn't lose brain power as fast as others. But it didn't make anyone gain or lose weight—it just watched what happened. So we can't say obesity causes slower decline; it might just be that healthier people who stayed obese were more likely to stick around.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
People who are obese tend to start with slightly lower brain function, but over time, their brain skills decline more slowly than those of people with normal weight — especially in skills like planning and problem-solving.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 572 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1This slowdown is equivalent to about 1–2 years of slower brain aging, but it doesn't make up for the lower starting point — so overall, obese adults still have worse brain function.
- 2Obese adults started with cognitive scores 0.36 points lower (on a 50-point scale), but their scores declined 0.03 points per year slower than normal-weight adults after accounting for blood pressure and glucose.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Neurology
Year
2022
Authors
E. Quaye, A. Galecki, Nicholas Tilton, Rachael T. Whitney, E. Briceño, M. Elkind, A. Fitzpatrick, R. Gottesman, Michael E. Griswold, A. Gross, S. Heckbert, T. Hughes, W. Longstreth, R. Sacco, S. Sidney, B. Windham, K. Yaffe, D. Levine
Related Content
Claims (4)
Obese adults show a slower rate of cognitive decline over time than adults with normal weight, even after accounting for blood pressure and blood sugar levels.
Obesity is associated with slower cognitive decline in both Black and White adults, and the strength of this association is the same across both groups.
Adults aged 61 who are obese have, on average, slightly lower cognitive test scores than adults of normal weight, even when accounting for blood pressure and blood sugar levels.
People with obesity show a slightly slower yearly decrease in executive function skills such as planning and decision-making compared to those without obesity, after accounting for blood pressure and blood sugar levels, but there is no similar pattern for memory decline.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.