not clear if this effect is universal for all kind of fiber. In the case of pectin, soluble fiber present in natural and processed foods, the evidence on the effect of its esterification degree on iron absorption is limited. Objective: To determine the effect of pectins with different degrees of esterificationon the absorption of non-heme iron in humans. Methods: Experimental, controlled, in block study. Thirteen apparently healthy adult women participated, who received in fasting state, 5 mg iron (FeSO4) without pectin (control) or with 5 g of citrus pectin, two with low esterification degree (Pectin27 with 27% esterification and Pectin36 with 36% esterification) and one with high esterification degree (Pectin67 with 67-73% esterification). Compounds were ingested on days 1, 4, 18 y 21. Iron doses were labeled with iron radioactive isotopes 55Fe y 59Fe. The iron status and incorporating isotopes to erythrocytes (iron absorption) were measured in blood at 18 and 36 days. Results: Two women had iron deficiency and one depleted iron stores. The geometric mean (range +/- 1 SD) of iron absorption of control was 18.2% (12.3%- 27.1%), iron with Pectin27 was 17.2% (10.2%-29.2%) and iron with Pectin36 was 15.3% (9.5%-24.6%), whereas iron absorption of iron with Pectin67 of high degree of esterification was 19.5% (10.0%- 38.0%). There were not statistically significant differences between the percentages of iron absorption. (Repeated measures ANOVA, p=0.22). Conclusions: The esterification degree of the pectin does not influence the absorption of non-heme iron.