NAMPT and type 2 diabetes mellitus: However, in a crossover study of 11 patients with overweight and type 2 diabetes (T2DM), the daily consumption of extra virgin OO enriched with 14.425 mg of phenols (though with an unspecified HT concentration) versus placebo for 4 weeks without diet modifications, significantly reduced BMI, body weight, fasting plasma glucose, glycated hemoglobin and visfatin levels [33].