The Influence of Iron and Zinc Supplementation on Iron Apparent Absorption in Rats Fed Vitamins and Minerals Reduced Diets

Abstract

Deficient human diet is usually reduced in many nutrients, but animal studies on iron absorption have been only carried out for rats fed well-balanced (control) and iron-deficient diets. The aim of this study was to evaluate the effect of iron or iron/zinc supplementation on iron apparent absorption (IAA) in rats fed a diet reduced in all vitamins and minerals (R). The study was conducted on 77, 6-week-old male Wistar rats in 3 stages as follows: stage I, 4-week period of adaptation to R diet (50% less vitamins and minerals compared to AIN-93M recommendations); stage II, 4-week supplementation period with iron (RSFe) or iron/zinc (RSFeZn); stage III, 2-week post-supplementation period (rats fed R diet). Feces samples to IAA determination were collected at the 20–22nd days of stage I and II and the 10–12th days of stage III. To determine the changes in IAA after introducing and discontinuation of supplementation, feces were collected for 3 days after introducing (stage II) and 5 days after the supplementation discontinuation (stage III). At the end of stage II, compared to R rats, the IAA was statistically significantly higher in RSFe and RSFeZn rats (30.3 ± 2.0% vs. 47.4 ± 1.2% and 51.0 ± 1.7%, respectively). After introducing iron or iron/zinc supplementation, the IAA stabilized fast already in the first day, while after discontinuation of the supplementation, at least 4 days was required to the stabilization. At the end of stage III, the IAA was significantly lower in RSFe (15.8 ± 6.6%) than in RSFeZn rats (43.4 ± 5.9%). In conclusion, to confirm that iron and zinc supplementation is more beneficial than iron supplementation only, especially after discontinuation of supplementation, further research among humans is necessary.

Genetic and agronomic zinc biofortification modify processing and nutritional quality of common wheat

“…AA of micronutrients describe their bioavailability in diet (Kondaiah et al, 2019). In this experiment, we found that both agronomic and genetic Zn biofortification significantly ( p < .05) decrease FeAA which may be related with higher Zn saturation in intestine, because both Fe and Zn use same channels for absorption in body (Kondaiah et al, 2019; Rolf et al, 2021). Lower decrease in Zincol‐2016 FeAA seems to be associated with its significantly ( p = .0001) reduced phytate content as compared to Johar‐2016, that inhibits Fe absorption in the body (Kondaiah et al, 2019).…”

“…Therefore, higher dietary Zn intake did not warrant better Zn nutrition, but it should be studied along with its absorbable amount (termed as retained here). Significant (p < .05) decrease in ZnAA with genetic and agronomic biofortification (Figure 1) may relate to higher Zn saturation in the animals intestine (Kondaiah et al, 2019;Rolf et al, 2021), as Zn excretion increased (Supporting Information: Table S2 and Table 5). Similar results have been depicted in Quails fed on Zn biofortified wheat: an increase in Zn intake and excretion (Sahin et al, 2021).…”

Anti-inflammatory and antioxidant effects of zinc and vitamin D on nicotine-induced oxidative stress in adult male rats

“…Zinc and iron can bind due to the chemical similarities between the two trace elements. Therefore, the inhibitory effect of zinc on iron absorption (and vice versa) may be related to zinc antagonistic to iron absorption in the intestinal tract (Rolf et al, 2021). The absorption and transport mechanisms of zinc and iron are chemically similar.…”

“…Zinc is one of the essential trace element that is necessary for the development and growth at all stages of organisms and plays an important role as coenzyme in many reactions (Rolf et al 2021). A long-term elevation of IL-6 is thought to be responsible for severe lung damage to the immune system and macrophage excitation syndrome.…”

Circulating and Tissues Concentrations of Selected Trace Elements in Response to Moderate Physical Exercise: Protective Effects of Cucurbita pepo Seeds Oil Extraction

“…Scientific evidence supports that pumpkin possesses various biological properties, such as antifatigue, antioxidant, and anti-inflammatory effects (11,39). The health benefits of pumpkin seeds may be attributed to their composition of several macro-and micronutrients, including proteins, triterpenes, lignans, phytosterols, polyunsaturated fatty acids, antioxidative phenolic compounds, carotenoids, tocopherol, and minerals (11,39,40). The recommended dietary allowances (RDAs) for trace elements, including Zn, Mg, iron, manganese, and Cu, are as follows: 15 mg/day for Zn, 420 mg/day for Mg, 18 mg/day for Iron, 2.3 mg/day for manganese, and 3 mg/day for Cu, for adults (5,41).…”