People who eat fast are more likely to develop type 2 diabetes, say researchers.
This could be because eating very quickly encourages weight gain, which can trigger the illness.
Scientists in Lithuania presented their finding at the International Congress of Endocrinology and European Congress of Endocrinology in Florence, Italy, the Daily Mail reported.
They looked at 702 people, including 234 who had just been diagnosed with type 2 diabetes.
They all filled in a detailed questionnaire about their lifestyles, which included sections on diets, exercise and whether they smoked.
Overweight women miss out on jobs because of 'fat discrimination'ne question asked them if they ate faster, more slowly or at the same speed as others.
They were also measured and weighed to calculate their body mass index, which determines whether they are obese.
The researchers found that those who admitted they ate more quickly than most other people were two-and-a-half times more likely to develop type 2 diabetes.
They claimed that this trend existed even once they had accounted for other causes such as obesity, smoking, diet and a family history of the illness.
"The prevalence of type 2 diabetes is increasing globally and becoming a world pandemic. It appears to involve interaction between susceptible genetic backgrounds and environmental factors," said lead researcher Dr Lina Radzeviciene from Lithuanian University of Health Sciences.
"It's important to identify modifiable risk factors that may help people reduce their chances of developing the disease," she noted.
The scientists did not explain why eating fast appeared to be linked to type 2 diabetes.
But obesity has long been recognised as one of the main causes of the illnesses.
Previous studies have found that people who eat quickly also eat more, and consequently are more likely to be overweight.
Experts think this is because their digestive system doesn't have a chance to send a signal to the brain that it is full.
But David Speigelhalter, a professor in the public understanding of risk at Cambridge University, warned that the study was too small to be meaningful.
"This is one of those many small studies that raise an interesting question but don't prove causation. It is a huge and unjustified jump to say that eating slower reduces your risk of getting diabetes," he stated.