Published in the BMJ, the researchers also found that increased consumption of milk, but not dark, chocolate was associated with long-term weight gain.
Chocolate contains high levels of flavanols (natural compounds found in fruits and vegetables) that have been shown to promote heart health and reduce the risk of diabetes.
But the link between chocolate consumption and risk of type 2 diabetes is controversial due to conflicting results.
In addition, most previous studies have not looked at whether eating dark and milk chocolate — which contain different amounts of cocoa, milk and sugar — may have different effects on the risk of type 2 diabetes.
To explore this further, researchers combined data from three long-term US observational studies of female nurses and male healthcare professionals with no history of diabetes, heart disease or cancer. was when he was recruited.
They analyzed the association between type 2 diabetes and total chocolate consumption for 192,208 participants and consumption of chocolate subtypes (dark and milk) for 111,654 participants during an average follow-up period of 25 years.
In the total chocolate analyses, 18,862 people developed type 2 diabetes.
After adjusting for personal, lifestyle, and dietary risk factors, the authors found that people who ate at least five servings of any type of chocolate per week had significantly lower rates of type 2 diabetes than those who did not. 10 percent less than those who rarely or never eat. Chocolate
In analyzes of chocolate subtypes, 4,771 people developed type 2 diabetes.
After adjusting for the same risk factors, people who ate at least five servings of dark chocolate a week had a 21 percent lower risk of type 2 diabetes, but no significant association was found for milk chocolate intake. went
The researchers also found that each additional weekly serving of dark chocolate reduced the risk of type 2 diabetes by 3 percent.
“Clinical trials are needed to confirm the results and help identify the reasons for the protective effect of dark chocolate,” the researchers said.