THIN people get diabetes too, scientists warn

One in five adults who are deemed a ‘healthy weight’ are at risk of developing diabetes, a new study claims.

And a third of slim people over the age of 45 also meet the criteria for prediabetes, experts say.

Prediabetes is defined as having higher blood glucose levels than normal – but not high enough for a diabetes diagnosis.

The condition puts people at a higher risk of developing type 2 diabetes and various cardiovascular problems.

Researchers from the University of Florida wanted to know if BMI measures were an effective method for diagnosing diabetes.

But they say their findings are a huge cause for concern as the adults in question wouldn’t be screened for the condition under current guidelines.

Lead investigator Dr Arch Mainous III from the University of Florida said: ‘We have an epidemic of diabetes right now and diabetes prevention is a key strategy to try to stem that tide.

‘One of the ways we can do this is to identify people with prediabetes, a high-risk state for development of diabetes, and intervene with drug or lifestyle modifications to keep them from transitioning to diabetes.’

They analysed data from the National Health and Nutrition Examination Survey – information regarding the health of adults and children in the US – between 1988 to 1994 and 1999 to 2012.

It focused on normal weight adults – with a BMI of between 18.5 to 24.9 - over the age of 20 who haven’t already been diagnosed with diabetes.

Within the first time frame, 10 per cent of people had prediabetes. But during the second study the number rose to 19 per cent.

They also found the percentage of people over the age of 45 with prediabetes increased by 11 per cent in the later study.

Dr Mainous said: ‘A large proportion of these people will develop diabetes, but we won’t be able to do any diabetes prevention with them because we aren’t looking for them under current screening guidelines.’ 

Because carrying more weight in the abdomen has been linked to diabetes and cardiovascular problems, the researchers evaluated participants waist circumference and waist-to-height ratio.

But they found an unhealthy waist size did not predict diabetes despite a slight increase in circumference between the two studies.

While roughly 6 percent of the normal-weight people had an unhealthy waist circumference in the first survey, almost 8 percent had a too-large waistline by 2012.

But more research is needed to determine the cause of prediabetes in people who are at a healthy weight, Dr Mainous said.

Although he believes it could be down to an increase in sedentary behaviour which means people with a normal weight have a high proportion of fat to lean muscle.

People with healthy weight obesity are more likely to develop metabolic syndrome, which can cause increased blood pressure, high blood sugar and abnormal cholesterol levels. 

He is planning a study that will evaluate the cost-effectiveness of screening all adults for prediabetes.

It comes as another report found more than half of people at high risk for diabetes are missed under current US screening guidelines. 

Guidelines issued in 2015 by the United States Preventive Service Task Force (USPSTF) recommend people undergo screening for diabetes if they are between 40 and 70 years old and classed as overweight or obese.

Under President Barack Obama’s health care law, the Affordable Care Act, all services recommended by the USPSTF must be fully covered by insurers.

But if a patient does not meet the criteria, they may have to pay out of their own pocket for a diabetes test. 

Professor Naveed Sattar from Glasgow University previously said: 'Weight will be a factor for anyone who develops type-2 diabetes.

 ‘The problem is the tipping point at which their weight makes them vulnerable to developing diabetes varies from person to person.

He said some people are genetically more prone to put on weight around their middle, liver and pancreas than they are to store it under the skin and that makes them more prone to diabetes.

When fat is stored in the liver and pancreas - where insulin is made - it interferes with the body’s ability to metabolise sugar.  

Further research as to why this happens is still needed, he says.

But it may be that these people store fat in the wrong place even when they are at a low weight or that their pancreas has lower insulin-making capacity.

Diabetes UK estimates that around 850,000 people have the condition without realising, and on average people will have symptoms for ten years before being diagnosed.

By then they already have some of the complications associated with the condition, such as blurred vision or even heart disease. 

Follow NEWS.am Medicine on Facebook and Twitter