Lycopene from fresh and unprocessed tomatoes is poorly absorbed by humans. Absorption of lycopene is higher from processed foods such as tomato paste and tomato juice heated in oil. The aim of the present study was to develop a food-grade lycopene formulation that is bioavailable in humans. A formulation of lycopene named "lactolycopene" has been designed in which lycopene is entrapped with whey proteins. Healthy subjects (n = 33; 13 men and 20 women) participated and were allocated randomly to one of the three treatment groups. After a 3-wk deprivation of dietary lycopene, subjects ingested 25 mg lycopene/d for 8 wk from lactolycopene, tomato paste (positive control) or a placebo of whey proteins while consuming their self-selected diets. Plasma lycopene concentrations reached a maximum after 2 wk of supplementation in both lycopene-treated groups and then a plateau was maintained until the end of the treatment. Increases in plasma lycopene at wk 8 were not different between supplemented groups (mean +/- SEM): 0.58 +/- 0.13 micromol/L with lactolycopene and 0.47 plus minus 0.07 micromol/L with tomato paste, although they were different from the control (P < 0.001). Similar time-concentration curves of lycopene incorporation were observed in buccal mucosa cells. Although lycopene was present mainly as all-trans isomers (>90%) in both lycopene supplements, plasma lycopene enrichment consisted of 40% as all-trans and 60% as cis isomers. The precursor of lycopene, phytofluene, was better absorbed than lycopene itself. The lactolycopene formulation and tomato paste exhibited similar lycopene bioavailability in plasma and buccal mucosa cells in humans