Your morning coffee could help to stave off type 2 diabetes, a new study suggests, but it's not down to the caffeine content.
Study co-author Fredrik Brustad Mellbye, of the Department of Endocrinology and Internal Medicine at Aarhus University Hospital in Denmark, and colleagues recently reported their results in the Journal of Natural Products.
Type 2 diabetes arises when the body is no longer able to produce enough insulin or use the hormone effectively. As a result, blood glucose levels may become too high.
Previous research has indicated that drinking coffee may help to lower the risk of developing type 2 diabetes. While some studies have attributed this association to the effects of caffeine - the well-known stimulant in coffee - other research has suggested that alternative substances in the beverage might be at play.
The new study from Mellbye and colleagues supports the latter theory, after finding that the coffee compound cafestol improved markers of type 2 diabetes in mouse models.
Cafestol: An antidiabetic drug?
To reach their findings, the team assessed three groups of mice, all of which were at high risk of developing type 2 diabetes.
For a total of 10 weeks, one group was fed a daily dose of 1.1 milligrams of cafestol, one group was fed 0.4 milligrams of cafestol daily, while the third group did not receive the compound (the controls).
After the 10 weeks, the researchers found that both groups that were fed cafestol experienced a 28 to 30 percent reduction in blood glucose levels, compared with the control group.
Also, mice fed the higher dose of cafestol showed a 42 percent improvement in insulin sensitivity, compared with the control group, as well as a 20 percent reduction in fasting glucagon, which is the hormone that increases blood glucose levels.
After the 10-week study period, the researchers isolated islets of Langerhans - which are pancreatic cells that normally produce insulin - from each group of mice.
The team found that the islets isolated from mice fed cafestol demonstrated a 75 to 87 percent increase in insulin production, compared with islets isolated from the control group.
According to Mellbye and colleagues, their findings show that "cafestol possesses antidiabetic properties" in mice at high risk for the disease.
"Consequently, cafestol may contribute to the reduced risk of developing T2D [type 2 diabetes] in coffee consumers and has a potential role as an antidiabetic drug."