Being too thin raises dementia risk
Contrary to what's been suggested by past research, older adults who are underweight have the highest risk for developing dementia. That's the conclusion of a new study at the London School of Hygiene and Tropical Medicine.
For their study, researchers analyzed health data for almost 2 million people living in the UK and tracked the data for up to 20 years. The researchers focused on body mass index (BMI) values, so they tried to rule out other factors that may contribute to dementia risk, such as alcohol, history of stroke or heart attack, as well as use of blood pressure drugs. All 1,958,191 people who were studied were between 45 and 66 years old at the start of the study, and had their medical information pulled from a large medical data base.
They found that the people with the lowest body mass index values had the highest risk of developing dementia. A BMI that’s considered normal is between 20 and 29. Those were were underweight (a BMI lower than 20) were found to be 34 percent more likely to develop dementia. Researchers also found that as BMI increased, the risk for dementia decreased. Those with BMI values in the obese category (over 40), had a 29 percent higher risk of dementia.
The results ran counter to those from previous smaller studies, which linked higher dementia risks with obesity. The researchers say these results do not quality, but rather that those who are underweight may need to be monitored more closely for cognitive decline.