Are you an Apple or a Pear?

I am of course refering to your general body shape. By which I mean do you carry excess weight (okay, let's be blunt about this, fat) around your stomach area, making you apple shaped, or do you carry your excess weight around your hips and buttocks, making you pear shaped. Why do I ask? Because research shows that this can affect your likelihood of suffering from kidney problems.

Now everyone knows that being overweight is unhealthy, and it is also suggested that if the extra weight is located around your abdomen - apple shaped, rather than around your hips, then there is an increased chance of suffering from cardiovascular problems. (Although some studies say there is not much difference, and being overweight with high blood pressure is one of the more important factors causing cardiovascular problem.)

But a recent study published in the Journal of the American Society of Nephrology (JSAN) reported that apple-shaped people have lower kidney function, lower kidney blood flow and higher blood pressure within their kidneys compared with "pear-shaped" people who carry their fat in their buttocks, hips and thighs. Those factors could lead to kidney disease.

The research examined the kidney function of 315 otherwise healthy men and women, and measured their waist to hip ratios - the group was generaly within the normal BMI range, not the obese range. Each unit increase in waist-to-hip ratio coincided with a 4 millimeter per minute loss of blood flow through the kidney's filters, a process called glomerular filtration. Typically, filtration rates drop 1 millimeter per minute per year of normal aging.
Glomerular filtration rate (GFR) is the volume of fluid the kidneys can filter in a given amount of time. It is used to assess the excretory function of the kidneys.

The researchers suspect that the higher blood pressure in the kidneys of the apple shaped subjects may be resonsible for the increased risk of developing renal problems. So treatment that reduces kidney blood pressure may be beneficial for people with this body shape. The study cited previous research that has shown that high blood pressure in the kidneys can be treated with salt restriction or medication.

The researchers speculate that the cause might be from the fat triggering inflammation or insulin resistance, which can impede blood flow, or fat creating free radicals, which can damage the kidneys at a cellular level.