Two slices of bacon, a hot dog or a serving of deli meat daily has been found to significantly boost the risk of getting type 2 diabetes, said a major US study.

The research by experts at the Harvard School of Public Health represents the largest study of its kind to date and appears in the American Journal of Clinical Nutrition.

Eating 50gr of processed red meat every day increased a person’s diabetes risk by 51 per cent, while eating 100gr of unprocessed red meat each day, about the size of a deck of cards, boosted the risk by 19 per cent.

However, those risks went down if the red meat was substituted with nuts, white meat, low-fat dairy or whole grain proteins.

“Clearly, the results from this study have huge public health implications given the rising type 2 diabetes epidemic and increasing consumption of red meats worldwide,” said senior author Frank Hu. “The good news is that such troubling risk factors can be offset by swapping red meat for a healthier protein.”

The data for the study came from questionnaire responses from more than 204,000 people in US nurses and health professionals’ studies. The subjects were tracked for between 14 and 28 years.

Researchers also updated a meta-analysis that included their data with other studies covering more than 442,000 participants.

Diabetes affects nearly 350 million adults worldwide, and more than 11 per cent of adults over age 20 – or 25.6 million people – in the United States have the disease, according to the US Centres for Disease Control and Prevention.

Type 2 diabetes, a chronic disease that involves high levels of blood sugar, is often caused by obesity, lack of exercise and unhealthy eating habits.