Being fat ‘damages your BRAIN – increasing your risk of Alzheimer’s disease’
People with a high BMI are more likely to suffer a decline in cognitive function, which increases the risk of developing dementia
THERE'S a whole host of good reasons to maintain a healthy weight.
Obesity is linked to a range of fatal chronic diseases, from heart disease to various cancers - and now experts warn it could increase your risk of dementia.
Carrying extra weight and having a high body mass index (BMI) can trigger cognitive decline in older adults, new research suggests.
The study found that those with a high BMI suffer inflammation in the brain, which is proven to have a detrimental effect on how the brain functions.
"The higher your BMI, the more your inflammation goes up," said Kyle Bourassa, lead author of the research, from the University of Arizona.
"Prior research has found that inflammation — particularly in the brain — can negatively impact brain function and cognition."
Cognitive decline is a normal part of ageing, even in healthy adults, and can have a significant impact on quality of life.
Having a lower body mass is just good for you, period. It’s good for your health and good for your brain
Kyle Bourassa, University of Arizona
People diagnosed with mild cognitive impairment are at increased risk of developing Alzheimer's - the most common form of dementia.
The new research may pave the way for new interventions that could lead to preventative measures and treatments in future.
Using two separate samples from the study — one of about 9,000 people and one of about 12,500 — researchers looked at ageing adults over a six-year period.
The scientists examined information on the participants' BMI, inflammation and cognition.
And, in both samples they found a correlation between a high BMI and a decline in cognitive function.
Bourassa said: "The higher participants' body mass at the first time point in the study, the greater the change in their CRP levels over the next four years.
“CRP stands for C-reactive protein, which is a marker in the blood of systemic inflammation in your body.
"Change in CRP over four years then predicted change in cognition six years after the start of the study.
“The body mass of these people predicted their cognitive decline through their levels of systemic inflammation."
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But Bourassa’s colleague David Sbarra pointed out that although the findings indicate a clear correlation between a high BMI and cognitive decline, the research does not definitively prove the causation.
Sbarra said: “The findings provide a clear and integrative account of how BMI is associated with cognitive decline through systemic inflammation, but we need to remember that these are only correlational findings.
"Of course, correlation does not equal causation.
"The findings suggest a mechanistic pathway, but we cannot confirm causality until we reduce body mass experimentally, then examine the downstream effects on inflammation and cognition."
A high BMI also puts people at risk of cardiovascular diseases, high blood pressure, type 2 diabetes, gallbladder diseases, osteoarthritis and certain types of cancer.
Bourassa said: "Having a lower body mass is just good for you, period. It’s good for your health and good for your brain."