PON1 and type 2 diabetes mellitus: Therefore, as the activity of serum-PON-1 has been reported to be lower in subjects with T2D [31], we have now shown that increased F&V intake augmented its activity, in serum and particularly in HDL3, in this T2D population, which was further supported by the positive correlation between the concentration of β-cryptoxanthin and the activity of PON-1 in HDL3 (r = 0.258, p = 0.043).