Some previous studies have shown that coffee drinkers are at a lower risk for developing Type 2 diabetes, but the reason was unclear. A new study published in ACS' Journal of Agricultural & Food Chemistry indicates the role of a substance called human islet amyloid polypeptide (hIAPP) in causing Type 2 diabetes. The researchers Ling Zheng, Kun Huang and colleagues decided to see if coffee's beneficial effects might be due to substances that block hIAPP. They identified two categories of compounds in coffee that significantly inhibited hIAPP. They suggest that this effect explains why coffee drinkers show a lower risk for developing diabetes. "A beneficial effect may thus be expected for a regular coffee drinker," the researchers conclude.