While prebiotic substances have attracted considerable attention in terms of their stimulatory effect on intestinal calcium absorption, the potential influence of probiotic bacteria on calcium absorption has received little research emphasis. Therefore, the objective of this study was to investigate the effect of well-characterized probiotics (Lactobacillus salivarius (UCC 1‚1‚8) and Bifidobacterium infantis (UCC 35624)) on calcium uptake and transepithelial calcium transport in human intestinal-like, Caco-2, cells in culture. Cells were seeded onto permeable transport membranes and allowed to differentiate, over 1‚6 d, into intestinal-like cell monolayers. Monolayers (n=1‚2ñ20/ treatment) were then exposed to E. coli, UCC 1‚1‚8, UCC 35624 (107 cfu/ml) or no bacteria (control) for 6 or 24 h prior to calcium transport studies. Calcium transport was unaffected by exposure of Caco-2 cells to E. coli, UCC 1‚1‚8 or UCC 35624 for 6 or 24 h. Calcium uptake into Caco-2 cell monolayers after 24 h was unaffected by UCC 35624, but was significantly (P<0.05) or tended (P=0.079) to be increased by UCC 1‚1‚8 and E. coli, respectively, relative to the control. In conclusion, the findings of this study which suggest that bacteria can enhance intestinal calcium uptake, if not calcium transport, highlights the need to undertake further studies in this, to date, vastly underinvestigated area.