Micronutrient Interactions: Impact on Child Health and ... - Idpas.org

Effects of Riboflavin Deficiency on the Handling of Iron
Strategies for improving the micronutrient
status of infants and children in developing
countries should include steps to
normalize riboflavin deficiency. In view of
the importance of an adequate riboflavin
status to normalize iron economy, strategies
to improve iron status in particular
should consider riboflavin. As has been
pointed out elsewhere, the relatively low cost
of this vitamin, coupled with a negligible risk
of toxicity, are arguments for its inclusion
in fortification programs (Liu et al. 1993).
Conclusions
Riboflavin depletion disturbs the normal
handling of iron. This is true whether the
deficiency is induced at around weaning or
in adulthood. It impairs absorption and increases
the rate of gastrointestinal loss of
endogenous iron. It may also reduce the efficiency
of iron use for heme synthesis. The
effects on absorption and gastrointestinal
loss appear to result from a hyperproliferation
of crypt cells and an increased rate
of transit of enterocytes along the villi, probably
leading to functionally immature villi.
A failure to increase villus number in the
small intestine, observed after weaning when
there is riboflavin deficiency, reduces the
absorptive surface area and contributes to
the effect on iron absorption. An increase in
villus length may be an adaptation to the
observed failure to increase villus number.
The effects of changes in the small intestine
are unlikely to be specific to iron.
Ethical Considerations
All studies involving human subjects were
carried out with the approval of the University
of London or University of Cambridge
Ethics Committee.
Acknowledgments
Financial support for some of the studies
referred to here was provided by The Medical
Research Council; Hoffmann-La Roche,
Ltd; and The Wellcome Trust (035705/Z).
References
Adelekan DA, Thurnham DI (1986a) Effects of combined
riboflavin and iron deficiency on the
haematological status and tissue iron concentrations
of the rat. J Nutr 116:1257–1265
Adelekan DA, Thurnham DI (1986b) The influence of
riboflavin deficiency on absorption and liver storage
of iron in the growing rat. Br J Nutr 56:171–
179
Bamji MS, Bhaskarham P, Jacob CM (1987) Urinary
riboflavin excretion and erythrocytes glutathione
reductase activity in preschoolchildren suffering
from upper respiratory infections and measles. Ann
Nutr Metab 31:191–196
Bates CJ (1987) Human riboflavin requirements, and
metabolic effects of deficiency in man and animals.
World Rev Nutr Diet 50:215–265
Bates CJ, Prentice AM, Paul AA, et al (1981) Riboflavin
status in Gambian pregnant and lactating women
and its implications for recommended dietary allowances.
Am J Clin Nutr 34:928–935
Bates CJ, Prentice AM, Paul AA, et al (1982) Riboflavin
status in infants born in rural Gambia, and the effect
of a weaning food supplement. Trans Roy Soc Trop
Med Hyg 76:253–258
Butler F, Topham RW (1993) Comparison of changes
in the uptake and mucosal processing of iron in
riboflavin-deficient rats. Biochem Mol Biol Int
30:53–61
Buzina R, Jusic M, Milanovic N, et al (1979) The effects
of riboflavin administration on iron metabolism
parameters in a school-going population. Int J
Vitam Nutr Res 49:136–143
Charoenlarp P, Pholphothi T, Chatpunyaporn P, Schelp
FP (1980) The effect of riboflavin on the hematologic
changes in iron supplementation of schoolchildren.
Southeast Asian J Trop Med Publ Health
11:97–103
Crichton R, Roman F, Wauters M (1975) Reductive
mobilisation of ferritin iron by reduced nicotinamide
adenine dinucleotide via flavin mononucleotide.
Biochem Soc Trans 3:946–948
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