TREH and diabetes mellitus: In an additional small nested case–control study comparing 48 individuals who initially had normal glucose tolerance, but who subsequently developed diabetes, with matched controls who remained free of diabetes in follow-up (Lindsay et al. 2002, Krakoff et al. 2003), baseline trehalase activity also did not predict diabetes (hazard ratio 1.18, 95 % CI 0.75–1.85, p = 0.48).