Twin study finds the amount of fat in the pancreas depends more on environmental factors than genetics; suggesting weight loss can help lower that fat—and diabetes risk.
Obesity and overweight can raise the risk of type 2 diabetes, as experts have known for years. Research has also found that a high amount of fat in the pancreas, known as intrapancreatic fat, is linked with poor functioning of the beta cells, which store and release insulin so sugar can get to your cells.
Now, a new study finds that lifestyle habits, not genetics, is the bigger driver affecting how much intrapancreatic fat you may have—and that can affect diabetes risk. Losing weight can help reduce pancreatic fat, other research shows.
The new study suggests that lifestyle intervention should be encouraged to minimize the accumulation of pancreatic fat, said lead author Gyorgy Jermendy, MD, a researcher at Semmelweis University, Budapest, Hungary. He presented the findings at the World Congress on Insulin Resistance Diabetes & Cardiovascular Disease in Universal City, CA.
His team recruited 77 pairs of twins, 47 identical pairs and 30 not. Their average age was mid-50s.
Studying both identical and fraternal twins allowed the researchers to assess with more certainty how much of an effect environment played and how much was attributable to genetics. The twins were all healthy and diabetes-free.
The researchers evaluated the amount of fat within the pancreas with a contrast computed tomography or CT scan. ''The more density, the more fat," Dr. Germendy said.
The researchers also had information on the twins' fasting blood glucose tests, hemoglobin A1C, cholesterol levels (HDL, LDL) and triglycerides. Dr. Germendy found that environmental factors (such as being overweight) accounted for 59% of the effect, while genetics accounted for 41%. "The environmental effects are much stronger," Dr. Germendy told EndocrineWeb. The effect of genetics was moderate, he said.
Perspective: Pancreatic Fat
The new study provides some valuable new information, said Selcuk Dagdelen, MD, professor of endocrinology and diabetes at Hacettepe University in Ankara, Turkey. He attended the Congress and reviewed the study. "We tend to blame genetics," he said.
"Twin studies are always valuable,'' he said. They can help separate out and clarify how much of an effect environment plays and how much genetics does, he said.
In 2015, a team of UK researchers showed that reducing pancreatic fat could bring insulin secretion function back to normal. In that study of 18 people with type 2 diabetes and nine without, who all had bariatric surgery, the weight loss reduced the pool of fat in the pancreas only in those with diabetes.
The researchers conclude that the reduction in pancreatic fat is associated with having the diabetes, not with decreased total body fat. In that study, participants had to lose a gram of fat in the pancreas to see insulin function return to normal. To lose that amount, the researchers said, a person usually must shed about 15% of their body weight.
1. Presentation, World Congress on Insulin Resistance Diabetes & Cardiovascular Disease, Dec. 1-3, 2016, Universal City, Ca.