Among obese American adults, control of blood sugar is worsening, leading to more diabetes and heart disease, a new study finds.
Too many blood sugar spikes
While blood pressure and cholesterol levels stayed relatively stable among obese adults, poor control of blood sugar levels led to a 37 percent increase in heart disease risk factors between 1988 and 2014, the researchers reported.
"Obese adults with cardiovascular disease risk factors may need more intense approaches – healthy diet, increased physical activity – to control blood sugar and achieve weight loss," said lead researcher Dr Fangjian Guo. He is an assistant professor of obstetrics and gynaecology at the University of Texas in Galveston.
After climbing over several decades, US obesity rates have leveled off. Still, about 35 percent of American adults are obese, according to background notes with the study.
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Obesity hinders the body's ability to process blood sugar. Over time, too many spikes in blood sugar can lead to type 2 diabetes, the researchers explained. Diabetes in turn is a known risk factor for heart disease and other health problems, such as vision loss and amputations.
However, weight loss can reverse this effect, the study authors noted.
"Controlling weight in obese adults to reduce the risk of developing type 2 diabetes should be a public health priority," Guo said.
A New York City specialist agreed, and recommended weight-loss medications as part of treatment.
"This is another wake-up call to provide not only more intense lifestyle interventions in this population, but also start with medications that can prevent diabetes and help weight loss," said Dr Joel Zonszein. He is director of the Clinical Diabetes Centre at Montefiore Medical Centre.
"In our health care system we chase diseases. However, we can now prevent diabetes and treat obesity early," he added.
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For the study, Guo and colleagues analysed data on more than 18,600 obese adults who took part in the US National Health and Nutrition Examination Survey over almost 30 years. The researchers used body mass index (BMI) – a calculation based on height and weight – to gauge body fat. Obesity is defined as a BMI of 30 or more.
Only 2 percent of obese adults had ideal heart health, a figure that remained stable throughout the study period.
Between 1988 and 2014, rates of diabetes rose from 11 percent to 19 percent, which was due to increases in blood sugar, the researchers said.
The investigators found that the rate of obese adults without the three key risk factors for heart disease – diabetes, high cholesterol and high blood pressure – held steady at just 15 percent.
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But the rate of obese adults with all three risk factors rose 37 percent – to nearly one in four, Guo said.
Risk for all three factors increased progressively from age 40 on. Young adults in their 20s and 30s had the lowest rate of all three, the study found.
"We have two choices: letting this population get sick and provide monies for treatment of complications and disability; or intervene early and prevent diabetes by encouraging weight loss, leading to a healthier and more productive life," Zonszein said.
The report was published online in the Journal of the American Heart Association.
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