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《交互式心脏血管和胸部手术》
Jaipur (Rajasthan), India.
Q.1. I would like to seek comments from the expert regarding tonic containing iron and zinc.
(i) Ascorbic acid (vitamin C) when administered along with oral iron, enhances absorption of iron; so, it is recommended that fruit juice or vitamin C be administered along with oral iron for better response.
(ii) If oral iron is taken with food, specially containing pulses rich in phytates, iron absorption is reduced. Thus iron is administered some time before food for better absorption.
(iii) Zinc administered along with oral iron results in reduced absorption of iron and vice versa. Many tonics containing iron and zinc with or without other vitamins are available in the market.
Reply
(i) Vitamin C whether naturally present in food or added in synthetic form, has an enormous effect on the absorption of nonheme iron from the diet. Vitamin C also enhances the absorption of iron fortificants that are soluble in gastric juice. However, these findings were obtained from studies that used ferrous sulfate as the iron fortificant, the form of iron that is frequently used in iron-containing pharmaceutical supplements. The effect of vitamin C on the absorption of iron derived from other iron fortificants, such as elemental iron powders and ferrous fumarate, has not been evaluated rigorously(1). As such a general statement of co administering vitamin C with all oral iron preparations for better response cannot be made.
(ii) Phytates markedly reduce iron absorption from diet and also bioavailability of iron from ferrous salt preparations. However, absorption of iron from iron amino acid chelates which are conjugates of the ferrous or ferric ion with amino-acids has been reported to be good in presence of phytates. Ferrous glycine sulphate (FGS) is the only salt of this group available in India. Absorption of iron polymaltose complex is also not affected by food or milk. Following intake of carbonyl iron preparations, iron absorption occurs slowly over 1 to 2 days. Hence, many newer iron preparations can be administered without consideration of the timing of feed(2).
(iii) Interaction between iron and zinc in ‘tonics’ has been a matter of considerable debate. In a recent study in Indonesia led by the Department of Public Health and Clinical Medicine at the University of Umea, Sweden, concludes that combined iron-zinc supplements may be less effective in preventing deficiencies of the minerals than individual supplementa-tion(3). In view of paucity of data on interactions between various forms of iron and zinc salts, it is preferable to use iron and zinc preparations separately, for the present, for children needing both the nutrients.
Multiple micronutrient formulations have been a subject of international interest, as it is assumed that single micronutrient deficiencies are unlikely especially in malnourished children. A novel strategy that is being developed is the use ‘sprinkles’ in which the micronutrients are encapsulated, or coated with lipids or other substances, to reduce adverse interactions among the nutrients. Sprinkles in sachets can be mixed with any food or liquid(4).
REFERENCES
1. Lynch SR, Stoltzfus RJ. Iron and Ascorbic Acid: Proposed Fortification Levels and Recom-mended Iron Compounds. J Nutr 2003; 133: 2978S-2984S.
2. Nagpal J, Choudhury P. Iron formulations in pediatric practice. Indian Pediatr 2004; 41: 807-815
3. Torbjrn Lind, Bo Lnnerdal, Hans Stenlund, Djauhar Ismail, Rosadi Seswandhana, Eva- Charlotte Ekstrm, et al. A community-based randomized controlled trial of iron and zinc supplementation in Indonesian infants: Interactions between iron and zinc. Am J Clin Nutr 2003; 77: 883- 890.
4. ACC/SCN. What works A review of the efficacy and effectiveness of nutrition interventions, Allen LH and Gillespie SR. ACC/SCN: Geneva in collaboration with the Asian Development Bank, Manila, 2001; p. 39-40.(Yash Paul,)
Q.1. I would like to seek comments from the expert regarding tonic containing iron and zinc.
(i) Ascorbic acid (vitamin C) when administered along with oral iron, enhances absorption of iron; so, it is recommended that fruit juice or vitamin C be administered along with oral iron for better response.
(ii) If oral iron is taken with food, specially containing pulses rich in phytates, iron absorption is reduced. Thus iron is administered some time before food for better absorption.
(iii) Zinc administered along with oral iron results in reduced absorption of iron and vice versa. Many tonics containing iron and zinc with or without other vitamins are available in the market.
Reply
(i) Vitamin C whether naturally present in food or added in synthetic form, has an enormous effect on the absorption of nonheme iron from the diet. Vitamin C also enhances the absorption of iron fortificants that are soluble in gastric juice. However, these findings were obtained from studies that used ferrous sulfate as the iron fortificant, the form of iron that is frequently used in iron-containing pharmaceutical supplements. The effect of vitamin C on the absorption of iron derived from other iron fortificants, such as elemental iron powders and ferrous fumarate, has not been evaluated rigorously(1). As such a general statement of co administering vitamin C with all oral iron preparations for better response cannot be made.
(ii) Phytates markedly reduce iron absorption from diet and also bioavailability of iron from ferrous salt preparations. However, absorption of iron from iron amino acid chelates which are conjugates of the ferrous or ferric ion with amino-acids has been reported to be good in presence of phytates. Ferrous glycine sulphate (FGS) is the only salt of this group available in India. Absorption of iron polymaltose complex is also not affected by food or milk. Following intake of carbonyl iron preparations, iron absorption occurs slowly over 1 to 2 days. Hence, many newer iron preparations can be administered without consideration of the timing of feed(2).
(iii) Interaction between iron and zinc in ‘tonics’ has been a matter of considerable debate. In a recent study in Indonesia led by the Department of Public Health and Clinical Medicine at the University of Umea, Sweden, concludes that combined iron-zinc supplements may be less effective in preventing deficiencies of the minerals than individual supplementa-tion(3). In view of paucity of data on interactions between various forms of iron and zinc salts, it is preferable to use iron and zinc preparations separately, for the present, for children needing both the nutrients.
Multiple micronutrient formulations have been a subject of international interest, as it is assumed that single micronutrient deficiencies are unlikely especially in malnourished children. A novel strategy that is being developed is the use ‘sprinkles’ in which the micronutrients are encapsulated, or coated with lipids or other substances, to reduce adverse interactions among the nutrients. Sprinkles in sachets can be mixed with any food or liquid(4).
REFERENCES
1. Lynch SR, Stoltzfus RJ. Iron and Ascorbic Acid: Proposed Fortification Levels and Recom-mended Iron Compounds. J Nutr 2003; 133: 2978S-2984S.
2. Nagpal J, Choudhury P. Iron formulations in pediatric practice. Indian Pediatr 2004; 41: 807-815
3. Torbjrn Lind, Bo Lnnerdal, Hans Stenlund, Djauhar Ismail, Rosadi Seswandhana, Eva- Charlotte Ekstrm, et al. A community-based randomized controlled trial of iron and zinc supplementation in Indonesian infants: Interactions between iron and zinc. Am J Clin Nutr 2003; 77: 883- 890.
4. ACC/SCN. What works A review of the efficacy and effectiveness of nutrition interventions, Allen LH and Gillespie SR. ACC/SCN: Geneva in collaboration with the Asian Development Bank, Manila, 2001; p. 39-40.(Yash Paul,)