Alginate Inhibits Iron Absorption from Ferrous Gluconate in a Randomized Controlled Trial and Reduces Iron Uptake into Caco-2 Cells

  title={Alginate Inhibits Iron Absorption from Ferrous Gluconate in a Randomized Controlled Trial and Reduces Iron Uptake into Caco-2 Cells},
  author={Anna Wawer and Linda J Harvey and Jack R. Dainty and Natalia P{\'e}rez-Moral and Paul A Sharp and Susan J. Fairweather-Tait},
  journal={PLoS ONE},
Previous in vitro results indicated that alginate beads might be a useful vehicle for food iron fortification. A human study was undertaken to test the hypothesis that alginate enhances iron absorption. A randomised, single blinded, cross-over trial was carried out in which iron absorption was measured from serum iron appearance after a test meal. Overnight-fasted volunteers (n = 15) were given a test meal of 200 g cola-flavoured jelly plus 21 mg iron as ferrous gluconate, either in alginate… 
Alginate-Iron Speciation and Its Effect on In Vitro Cellular Iron Metabolism
The results infer alginate as being useful in the chelation of excess iron, especially in the context of inflammatory bowel disease and colorectal cancer where excess unabsorbed luminal iron is thought to be a driver of disease.
The chelation of colonic luminal iron by a unique sodium alginate for the improvement of gastrointestinal health.
Manucol LD could be useful for the chelation of this detrimental pool of unabsorbed iron and it could be fortified in foods to enhance intestinal health.
The Safety and Tolerability of a Potential Alginate-Based Iron Chelator; Results of A Healthy Participant Study
Results from this study suggest that daily ingestion of 3 g alginate was well tolerated with very minor side effects and there were no detrimental changes in a variety of haematological parameters or the intestinal microbiome.
The use of alginates and polyphenols in medicinal iron chelation for the improvement of colonic health
It has been demonstrated that a unique alginate, Manucol LD, is an excellent candidate for sequestering luminal iron present in the gastrointestinal tract and underpin the rationale in utilising these types of natural and safe bio-polymers for the prevention and treatment of gastrointestinal disease.
In Vitro Iron Bioavailability of Brazilian Food-Based by-Products
It is suggested that cucumber and pumpkin peel could be valuable alternative sources of bioavailable Fe to reduce iron deficiency in at-risk populations.
The Use of Chitosan, Alginate, and Pectin in the Biomedical and Food Sector—Biocompatibility, Bioadhesiveness, and Biodegradability
The purpose of this review is to summarize the most compatible biopolymers such as chitosan, alginate, and pectin, which are used for application in food, biotechnological processes, and biomedical applications.


Evidence for an enhancing effect of alginate on iron availability in Caco-2 cells.
Alginate beads delivered available iron to Caco-2 cells, indicating that they are a promising vehicle for soluble iron with potential use in food fortification programs.
EDTA and the absorption of iron from food.
Na2EDTA added to meals with molar ratios of EDTA to iron between 1.0 and 0.25 significantly increases iron absorption provided the meal is of low iron bioavailability, according to standard double isotope techniques.
Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans.
Addition of calcium chloride to wheat rolls significantly reduced iron absorption, suggesting that the effect of calcium is related to the mucosal transfer of iron.
Inhibitory effect of calcium on non-heme iron absorption may be related to translocation of DMT-1 at the apical membrane of enterocytes.
The data suggest that calcium reduces iron bioavailability by decreasing DMT-1 expression at the apical cell membrane, thereby downregulating iron transport into the cell.
Low-pH cola beverages do not affect women's iron absorption from a vegetarian meal.
Although there was no effect of low-pH drinks on iron bioavailability in healthy women, their effect on absorption of fortification iron that requires solubilization in dilute acid, such as reduced iron, and in individuals with low gastric acid production,such as older people and individuals with Helicobacter pylori infection, warrants further investigation.
Serum iron curves can be used to estimate dietary iron bioavailability in humans.
Serum Fe curves were highly reproducible and were affected as expected by food composition, and the extent and rate of absorption of nonheme iron from meals, rather than in individuals, can be investigated with such subjects without the need for isotopes.
Calcium does not inhibit the absorption of 5 milligrams of nonheme or heme iron at doses less than 800 milligrams in nonpregnant women.
An isolated effect of calcium (as chloride) on absorption of 5 mg of iron provided as nonheme (as sulfate) and heme ( as CRBC) iron was observed at doses higher than previously reported from single-meal studies.
Alginate, small bowel sterol excretion, and absorption of nutrients in ileostomy subjects.
Five of six subjects showed a decreased apparent absorption of iron and manganese with alginate, which, however, was not statistically significant, and the increased fatty acids excretion may be explained by the binding or trapping of fatty acids in the gel matrix formed by alginates.
Calcium and iron absorption--mechanisms and public health relevance.
  • B. Lönnerdal
  • Biology
    International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition
  • 2010
The effect of Ca on Fe absorption may be of short duration and adaptation may occur with time, which may explain why studies on long-term Ca supplementation of different groups fail to show any adverse effects on Fe status.