How do you know if you might get dementia or Alzheimer's in later life? One tell-tale sign could be a measurement that's known as SAD (sagittal abdominal diameter), which is the distance from your back to your upper abdomen.
If you have a high SAD score - which is anything over 25 centimetres - when you're in your 40s, your chances of developing dementia or Alzheimer's triple, new research suggests.
Researchers measured the SAD of 6,583 participants between the years 1964 and 1973, and, of these, 1,049 developed dementia around 36 years later. Those with a high SAD and normal body-mass index (BMI) - the standard measure of obesity - were three times more likely to develop dementia than those who had a low SAD measurement. Those who had a high SAD measurement and high BMI had the highest risk of dementia at 3.6 times compared with those who had normal SAD and BMI scores.
To get an accurate SAD reading, you need to measure the distance from your back to your upper abdomen, midway between the top of the pelvis and the bottom of the ribs. You should be standing when you measure.
(Source: Neurology, 2008; doi: 10.1212/01.wnl.0000306313.89165.ef).