Dr Olga Titova, an epidemiologist at Uppsala University who led the research, suggested snus raised the risk of diabetes because it contained nicotine.

In the study published Monday, scientists at Uppsala University, about 40 miles north of the Swedish capital Stockholm, analyzed data from 3,700 people aged 56 to 95 years old who were tracked between 2009 and 2017.

In the analysis, scientists compared the rate of type 2 diabetes cases in each group with that in non-smokers to establish whether they had a higher risk of the disease.

Results were adjusted for demographic factors including age, sex, education, alcohol intake, coffee consumption, and exercise.

The researchers concluded: 'This study indicates that current and former smoking are associated with an increased risk of Type 2 diabetes in middle-aged and older individuals.

Smokeless tobacco is already known to put the user at higher risk of cancer in the mouth, the esophagus — which connects the throat and stomach — and pancreas.