It is well known that vitamin C is an important enhancer of nonheme iron bioavailability due to its high reducing capacity. Camu-camu, a fruit that grows in the jungle of Peru, contains high amount of vitamin C (2,780 mg per 100 g). In this study, we investigated the effect of camu-camu on nonheme iron bioavailability from two different meals (rice with lentils and wheat flour porridge) using an in vitro Caco-2 cell model. These two meals were treated with three different camu-camu juice concentrations (C 0 = 0 g, C 1 = typical consumption, and C 2 = 3X typical consumption). The results showed that camu-camu reduced rather than enhanced nonheme iron bioavailability. The inhibiting trend was significant (p<0.0001) in the wheat flour porridge (from 124 to 91 and 35 µg ferritin/µg protein, for C 0 , C 1 and C 2 , respectively). With the rice with lentils, there was no significant effect of camu-camu due to the high polyphenols and phytate contents of the meal. Relative bioavailability values obtained showed significant decrease with increasing camu-camu juice concentration for both meals. As expected, the ascorbic acid added to the meals at a concentration equivalent to that present in C 2 , had no effect on bioavailability with rice meal but increased significantly with wheat flour meal. The findings of this study suggest that camu-camu, in the traditional way of preparation, may significantly reduce nonheme iron bioavailability because of its high polyphenol content which overrides the beneficial effect of its high ascorbic acid content. Unauthenticated Nonheme iron content determinationNonheme iron content of each meal was determined by the modified method of Torrance & Bothwell [1968] using ferrozine instead of bathophenanthroline disulfonic acid as a chromogen in a microplate assay [Chidambaram et al., 1989]. MealsTwo meals, namely rice with lentils and wheat flour porridge which are common dishes in Peru were prepared as a regular adult portion sizes and used in the experiments. The rice and lentil meal was prepared from 110 g of rice and 70 g of lentils. These ingredients were cooked and homogenized with iron-free water (260 mL). In preparing the wheat flour porridge, wheat flour (28 g) was dissolved in water, heated to boil and it was further cooked after adding sugar (11 g) and powdered milk (17 g). Both meals were weighed and saved as small batches at -20 o C. Camu-camu juice was prepared by mixing the pulp with water 1:5 as it is usually consumed as a refreshment drink in 1:5 water dilution (240 mL per serving). Three different treatments in triplicates were prepared with each meal as follows. Water (C 0 ) was added to the first aliquot; Two different amounts of Camu-camu juice were added to the second (C 1 ) and the third (C 2 ) sample. C 1 represents typical intake level in Peru and C 2 contains three times the vitamin C concentration in C 1 . The amount of juice added (C 1 ) was proportional to the fraction of one serving of meal. To further understand the effect of camu-camu on iron bioavailability,...