Researchers used data from a large US study that followed more than 8,200 people over the age of 50 for 24 years. They measured body mass index (BMI) over time and tested cognitive skills such as memory and executive function. Executive function means planning, organizing and concentrating.
The study found that higher BMI over time led to faster declines in thinking and memory. Every unit increase in BMI was linked to a quicker decline, and the link was strongest around year eight. The effect was most pronounced in adults over 65.
Obesity (BMI of 30 or higher) was tied to worse brain health. Researchers list possible causes: inflammation, less blood flow to the brain, and insulin resistance. They also say that managing weight could lower the rate of decline in just two years.
Difficult words
- body mass index — A number showing weight related to height.BMI
- cognitive — Related to thinking and mental skills.
- executive function — Skills for planning, organizing and concentrating.
- decline — A reduction or loss in ability or quality.declines
- inflammation — Body reaction that causes redness or swelling.
- insulin resistance — When the body does not use insulin well.
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think managing weight is important for older adults? Why?
- Have you or someone you know tried to change weight for health? What happened?
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