These findings come from the Singapore Chinese Health Study, which recruited 63,257 adults aged 45-74 years between 1993 and 1998, and then followed them up for an average of about 11 years. The study found a positive association between intakes of red meat and poultry, and risk of developing diabetes. Specifically, compared to those in the lowest quartile intake, those in the highest quartile intake of red meat and poultry had a 23 per cent and 15 per cent increase in risk of diabetes, respectively, while the intake of fish/shellfish was not associated with risk of diabetes. The increase in risk associated with red meat/poultry was reduced by substituting them with fish/shellfish.

Source: Eating meat linked to higher risk of diabetes — ScienceDaily