Men develop type 2 diabetes at a lower BMI (body mass index) than women, according to a new study by clinical researchers in Scotland expected to be published in a scientific journal this week. Their findings may explain why in many countries, men are more prone to the disease than women.

Being overweight is a major risk factor for type 2 diabetes, but this study appears to show that men have to gain less weight than women to develop the condition, said the lead researcher Professor Naveed Sattar, of the Institute of Cardiovascular & Medical Sciences at the University of Glasgow.

Body Mass Index is a person’s weight in kg divided by their height in metres squared and is used in health research and practice as a measure of obesity.

Type 2 diabetes is a condition that develops when there is too much sugar in the blood and the body can’t control it. This upsets several organs, and appears also to be linked to how much fat is in organs like the liver and also the muscles. According to information from the NHS, about 2.5 million people in the UK have type 2 diabetes.

Sattar said there are several risk factors for developing the disease, including age, ethnicity, family history, and of course, being overweight.

But this study appears to show that men don’t have to be as overweight as women to develop the disease:

“In other words, men appear to be at higher risk for diabetes,” said Sattar.

For their study, Sattar and colleagues analyzed data from 51,920 men and 43,137 women living in Scotland who had been diagnosed with type 2 diabetes and compared their BMI rates (measured within one year of diagnosis), taking into account factors like age and smoking status.

They found that the mean BMI at diabetes diagnosis was 33.69 in the women but only 31.83 in the men. This difference was even greater in the younger age groups.

Sattar suggests one of the reasons why women should develop diabetes at higher BMIs than men could be because of the way fat is distributed around the body.

Generally, men without diabetes have more fat around the abdomen and in the liver than women, who conversely tend to carry a greater proportion of their body fat under the skin, the so-called “subcutaneous fat” which is thought to be less risky for type 2 diabetes and other health problems.

Dr Victoria King, Head of Research at Diabetes UK, said studies like this one helps us understand why men tend to be more prone to type 2 diabetes, and give us”greater insight into what we can do to improve prevention of Type 2 diabetes”.

She said Diabetes UK urges all men and women to lower their risk for type 2 diabetes by shedding those excess pounds, eating a healthy and balanced diet and exercising regularly.

The Wellcome Trust through the Scottish Health Informatics Programme (SHIP) and the Scottish Government, and NHS Research Scotland through the Scottish Diabetes Research Network, provided funds for the study.

Written by Catharine Paddock