People who increased their consumption of red meat during a four-year period were more likely to develop Type 2 diabetes in a subsequent four-year period, according to an analysis involving about 150,000 people.

The analysis, led by researchers at the National University of Singapore, took data from three long-running Harvard University studies involving mostly nurses and doctors. The results were published online Monday in JAMA Internal Medicine, a journal of the American Medical Association. The studies were funded by grants from the National Institutes of Health.

While prior studies have also found a link between red-meat consumption and the development of Type 2 diabetes, the new analysis is believed to be the first time researchers have tracked changes in red-meat consumption over time with the risk of developing Type 2 diabetes. Study participants filled out detailed questionnaires about the types of food and drinks they consumed at the beginning of the study and every four years. The analysis looked at some 20 years of data.

Broadly, the study showed that, compared with a group of people who had no change in red-meat intake, increasing red-meat consumption by more than a half-serving per day over a four-year period was associated with a 48% increase in the risk of developing Type 2 diabetes during the next four years.

However, reducing red-meat consumption by the same amount during the same time period didn't cut the risk of diabetes during the next four years. It did reduce the risk by 14% over a longer time period, though.