A British health group is urging men to get naked, stand up straight and look down to check if they can see their penis. They say men who can't see their appendage are obese and are at risk of losing up to nine years of their life.

The men's health awareness website WeLoveOurHealth.co.uk has launched the test dubbed "The Big Check" to encourage men to gauge their weight by taking a serious look at their manhood.

The website recently conducted a poll of 1,000 British men and found that about 33 percent of men between 35 and 60 years old cannot see their penis because of their bellies.

Previous research has suggested that this "blind spot" leaves men with excess belly fat more prone to develop type 2 diabetes, colon cancer, heart disease and other health problems.

"If your stomach is starting to obstruct the view of your manhood you shouldn't ignore it," the website warned. "Not only can it knock years off your lifespan but it could put you at serious risk from life threatening illness."

Campaign leader Dr. Sarah Brewer told MSN that men need to start taking better care of their bodies.

"Men care more about maintaining their cars than their own bodies, and often only see the doctor if told to by a female partner or relative," she said.

Brewer encourages men who cannot see their privates to start living healthier to shrink their bellies.

Being overweight is associated with a number of health conditions, especially is the weight is carried around the middle, which is why waist measurement is considered a more accurate reflection of a person's health than their body mass index, according to a recent study from the Mayo Clinic.

"Our research shows that if a person has a normal BMI, this by itself should not reassure them that their risk for heart disease is low," study researcher Dr. Francisco Lopez-Jimenez said in a statement. "Where their fat is distributed on their body can mean a lot."

"Health professionals need to educate patients about the importance of having a healthy weight and a normal weight-to-hip ratio. Promotion of healthy lifestyle including healthy eating and exercise is perhaps the best strategy," co-researcher Dr. Karine Sahakyan said in a statement.