Bioavailability of zinc from NutriSet zinc tablets compared with aqueous zinc sulfate

Abstract

Background/Objectives: The apparent widespread extent of zinc (Zn) deficiency in developing countries and the efficacy of oral Zn supplements as an adjunct to oral rehydration therapy make oral Zn supplementation an increasingly important modality in clinical medicine and public health. In this study we aimed to compare the relative bioavailability of oral doses of 30 mg of Zn in two dosing forms Subjects/Methods: In total, 10 healthy male volunteers ingested oral Zn doses with 200 ml plain water at about 0830 hours in the fasting state on two occasions, once as 30 mg of Zn in an aqueous solution of reagent grade zinc sulfate (ZnSO 4 ) and another time as 1.5 NutriSet Zn tablets (Nutriset, Malaunay, France); on a third occasion, only plain water was consumed. Venous blood specimens were collected at baseline, 60, 120, 180 and 240 min after ingestion and the plasma Zn was measured for each sample. Results: The relative bioavailability of oral Zn from a commonly used, tableted (NutriSet) form is only about half of that of a reference dose of aqueous ZnSO 4 as indicated by the area under the curve of serial plasma Zn excursion and maximal change in circulating Zn. Conclusions: Reduced or absent functional outcomes in Zn intervention trials may derive, in part, from a lower than anticipated intestinal uptake of the Zn in the tableted form.

Evaluating the cost-effectiveness of preventive zinc supplementation

“…Tran et al [59] found that the fractional absorption of zinc ranged from 0.62 to 0.73 for aqueous zinc sulfate doses of 2 mg to 15 mg, with declining fractional absorption for 20 and 30 mg dosing. Solomons et al [60] compare the absorption of aqueous zinc sulfate with the absorption of NutriSet tablets, and find that aqueous zinc administration doubles the bioavailability of zinc compared to the NutriSet tabs. To date, no evidence on the health impact of aqueous zinc is available.…”

Randomised controlled trial for high-dose intravenous zinc as adjunctive therapy in SARS-CoV-2 (COVID-19) positive critically ill patients: trial protocol

“…The upper limit for daily zinc intake in an adult is 40 mg. 22 However, when 30 mg of elemental zinc was given orally to humans, it resulted in an only 1.8-fold increase in plasma zinc in the first 4 hours. 23 A similar study in humans where elemental zinc (30 mg/d) or placebo were given orally for 6 months showed a statistically significant in the plasma zinc from 14.18±1.75 μmol/L in the placebo group to 17.18±3.48 μmol/L in the zinc group. 24 Oral delivery of zinc is affected by several factors, including normal variations in gut zinc absorption, dietary factors such as the presence of phytate, and interactions with other metal ions.…”

Zinc supplementation as an adjunct therapy for COVID‐19: Challenges and opportunities

“…82 When 30 mg of elemental zinc was given orally to humans, it resulted in an only 1.8-fold peak increase in plasma zinc to 27 ± 12 μmol/L from a baseline of 15 ± 5.1 μmol/L over 4 hours. 82 Feillet-Coudray et al showed oral supplementation of 30 mg zinc per day over 6 months resulted in a marginal increase in the plasma zinc from 14 ± 1.7 μmol/L in the placebo group to 17 ± 3.5 μmol/L in the zinc group. 83 Using a preclinical large animal model of sheep, which closely resemble the pathophysiology observed in humans, a study by O'Kane et al showed that plasma zinc levels needed to be raised by 7-fold from a baseline concentration of 11 ± 0.4 μmol/L to 70 ± 5.8 μmol/L to protect the sheep against renal ischaemia reperfusion injury.…”

“…Zinc is primarily supplemented orally. Solomons et al demonstrated that different formulations of oral zinc had different bioavailability; for example, consumption of 30 mg of zinc as Nutriset tablet (ZinCfant®) resulted in lower plasma zinc when compared to an aqueous solution of zinc sulphate which contained the same amount of elemental zinc 82 . When 30 mg of elemental zinc was given orally to humans, it resulted in an only 1.8‐fold peak increase in plasma zinc to 27 ± 12 μmol/L from a baseline of 15 ± 5.1 μmol/L over 4 hours 82 .…”

“…Solomons et al demonstrated that different formulations of oral zinc had different bioavailability; for example, consumption of 30 mg of zinc as Nutriset tablet (ZinCfant®) resulted in lower plasma zinc when compared to an aqueous solution of zinc sulphate which contained the same amount of elemental zinc 82 . When 30 mg of elemental zinc was given orally to humans, it resulted in an only 1.8‐fold peak increase in plasma zinc to 27 ± 12 μmol/L from a baseline of 15 ± 5.1 μmol/L over 4 hours 82 . Feillet‐Coudray et al showed oral supplementation of 30 mg zinc per day over 6 months resulted in a marginal increase in the plasma zinc from 14 ± 1.7 μmol/L in the placebo group to 17 ± 3.5 μmol/L in the zinc group 83 …”