Storing fat in particular locations around the body increases the risk of certain heart problems, according to researchers.
Boston University School of Medicine (BUSM) scientists found fat stored around the heart, aorta and inside the liver is associated with cardiovascular functions, such as slower cardiac pumping.
They said body mass index (BMI), the common measure for obesity, does not reliably predict how much fat is stored around these organs.
The study, published online in Obesity, compared the fat volumes in thin, healthy people with an average BMI of 22, to people with BMIs over 30 and high blood pressure or diabetes.
Using proton MR spectroscopy and magnetic resonance imaging (MRI), BUSM researchers collected data on aortic compliance, cardiac function, intra-hepatic lipid content and pericardial and periaortic lipid volumes.
They also measured the subjects' fasting plasma lipoproteins, free fatty acids, glucose and insulin, in a method they claim took less than an hour and could be adapted for future individual treatment.
Project leader James Hamilton said: "Our study found that fat collection around the heart, the aorta and within the liver is clearly associated with decreased heart functions and that an MRI can quickly and noninvasively measure fat volume in these areas."
"It's great knowledge. I am teaching "Health Assessment" to BScN yr one students. While teaching "Nutritional Assessment" I teach students about BMI. It's very helpful to share this knowledge to my students because many of my students are overweight. We don't take things seriously as being nurses we are caring for others and not caring for ourselves and we say all the time I have no time for me to care for myself" - Nasreen, Pakistan
"As a community rehabilitation nurse we use BMI when screening patients, this article is very interesting and confirms the controversial use of BMI in measuring cardiovascular risk" - Joanne Toller, Birmingham