A new study suggests that people who go on to develop dementia often start losing weight and body fat years before they are diagnosed.
The study, published in JAMA Network Open, also found that these individuals had higher levels of “good” cholesterol, known as HDL, before their condition was recognized.
Researchers led by Dr. Zimu Wu at Monash University in Australia analyzed health data from thousands of older adults. The participants were part of the Aspirin in Reducing Events in the Elderly (ASPREE) study, which looks at how aspirin affects aging.
The team compared 1,078 people who were later diagnosed with dementia to 4,312 similar people who did not get the condition. Both groups were similar in age and background, making the comparison fair.
The results showed a clear pattern: people who developed dementia had lower body mass index (BMI) and smaller waist sizes for at least seven years before their diagnosis. In fact, in the ten years leading up to dementia, their BMI and waist size dropped more quickly than in those who stayed healthy.
This suggests that unexplained weight loss in older adults—even if they seem healthy—could be an early warning sign of memory and thinking problems.
The study also found that people with dementia had higher HDL cholesterol levels several years before their diagnosis.
However, these levels started to drop closer to when the disease was detected. Researchers also noticed that these individuals had slightly higher levels of LDL (bad cholesterol) and total cholesterol, but these differences weren’t very strong.
Blood pressure and fat levels in the blood also changed over time. People who later got dementia had lower systolic blood pressure (the top number in a blood pressure reading) and lower triglyceride levels up to ten years before being diagnosed.
Triglycerides are a type of fat in the blood usually linked to heart health. While high levels can be harmful, this study suggests that very low levels may also be related to dementia risk.
These findings suggest that changes in weight, cholesterol, and blood pressure could be early signs that something is wrong—possibly even before memory loss begins. However, scientists aren’t sure if these changes actually cause dementia or if they are simply part of the disease process that starts in the body before symptoms show up.
One important takeaway is that doctors might want to keep a closer eye on older adults who are losing weight without trying or whose cholesterol levels are dropping for no clear reason. It may be a clue that something more serious, like dementia, could be developing.
The study does have some limitations. It doesn’t prove that weight loss or changes in cholesterol cause dementia—only that they are linked. Also, some researchers involved in the study have ties to the pharmaceutical industry, which readers should keep in mind.
Still, the results add to growing evidence that dementia affects not just the brain, but the whole body. More research is needed to understand how these changes happen and whether they can be used to prevent or delay the condition.
If you care about dementia, please read studies about a simple solution to fight dementia and big causes of memory loss, dementia you need to know.
For more health information, please read studies that people who take high blood pressure medications have lower dementia risk and early indicators of dementia: 5 behaviour changes to look for after age 50.
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