The potential cholesterol-lowering effect of a new fermented milk product was tested in a homogeneous group of Danish men (all 44-year-old; n = 58) in a randomised, double blinded and placebo-controlled study. Two hundred ml of the fremented milk or placebo (chemically acidified) was taken daily for six weeks. After these six weeks total cholesterol decreased significantly in the fermented milk group by -0.37 mmol/l (confidence interval: -0.51 to -0.23 mmol/l) and no changes were observed in the placebo group (-0.02 mmol/l) (p < 0.01). This decrement in total cholesterol could be completely ascribed to a reduction of LDL-cholesterol by 10% (i.e. -0.42 mmol/l), since HDL-cholesterol and triglyceride were unchanged in both groups during the study. Thus, in the present short term study, the tested fermented milk product was able to reduce LDL-cholesterol in middle-aged men.