This suggests that a quarter of the UK population could be at risk of Alzheimer’s, with one in four adults considered overweight or obese.
Many of us are aware of some of the most common signs of Alzheimer’s disease. A progressive condition that affects the brain it can lead to gradual memory loss, and behavioural and mood changes.
However, research has suggested that a physical sign of the disease could appear on the body decades before the first signs of memory loss. Scientists have discovered a connection between visceral fat and the abnormal brain proteins associated with Alzheimer’s, potentially up to 20 years before symptoms emerge.
Visceral fat is the name for belly fat that is found deep within your abdominal cavity. It surrounds important organs, including your stomach, liver and intestines.
While visceral fat is often considered “invisible” or “hidden fat” there are ways to tell if you have too much of it – including by measuring your waist, your waist-to-hip ratio and your body shape. The study by researchers at Washington University School of Medicine examined 80 cognitively healthy adults with an average age of 49.
Just over half of the participants (58 percent) were classified as obese, with an average body mass index (BMI) of 32.31. For reference, a BMI between 18.5 and 24.9 is considered healthy.
Utilising imaging techniques, the team mapped participants’ body composition and brain chemistry in detail. Brain positron emission tomography (PET) scans allowed them to track the build-up of amyloid and tau proteins, which are hallmark indicators of Alzheimer’s disease.
MRI scans were also used to measure different types of body fat. Researchers found a striking link between higher visceral fat levels and amyloid and tau build-up.
Lead study author Dr Mahsa Dolatshahi said in a media release: “Higher visceral fat was associated with higher PET levels of the two hallmark pathologic proteins of Alzheimer’s disease—amyloid and tau.” It was concluded that visceral fat accounted for 77 percent of the effect of high BMI on protein accumulation.
Whereas other fat types showed no similar correlation. The study also revealed that higher insulin resistance and lower levels of “good” cholesterol (HDL) were linked to increased brain protein build-up.
Senior study author Dr Cyrus A. Raji commented: “A key implication of our work is that managing Alzheimer’s risk in obesity will need to involve targeting the related metabolic and lipid issues that often arise with higher body fat. Knowing that visceral obesity negatively affects the brain opens up the possibility that treatment with lifestyle modifications or appropriate weight-loss drugs could improve cerebral blood flow and potentially lower the burden of and reduce the risk for Alzheimer’s disease.”
In the UK around one in four adults are considered overweight or obese. If you are concerned about your weight you should speak to your GP.