Zinc nutrition in celiac sprue.

Zinc nutritional status was examined in 10 adult patients with biopsy-proven celiac disease; five of these patients were clinically well on gluten-free diets at the time of study. Plasma zinc and taste acuity were used as indices of zinc nutrition. Depression of plasma zinc and lowered taste discrimination were observed among the untreated patients, and some patients who were otherwise in clinical remission also had impaired zinc nutrition. With confirmation of plasma copper depression in patients with celiac sprue, these observations indicate that trace metal deficiency is another common nutritional complication of adult celiac disease.     

Folate status of adult males living in a metabolic unit: possible relationships with iron nutriture

Folate and iron status was monitored at monthly intervals in 40 adult males who were living in a metabolic unit for 2 to 8 months and consuming diets containing 150 to 250 micrograms of folate per day. There were significant (p less than 0.02) declines in hematocrit, serum folate, and serum ferritin. Men who participated in studies for 6 months or more or those with initial serum folate levels more than 10.5 ng/ml and erythrocyte folate levels more than 481 ng/ml also exhibited a highly significant (p less than 0.001) decline in red blood cell folate. Men with erythrocyte folate below 480 ng/ml or serum folate below 10 ng/ml and who participated in the studies for less than 5 months showed little or no change in folate status. The findings may reflect adjustments in body folate to reflect dietary intakes. Also a folate intake of 200 +/- 68 micrograms/day appeared to be adequate for maintenance of folate stores in adult males. A correlation between iron stores and folate status was also observed. However, this relationship may be coincidental.     

Mineral contents of brans passed through the human GI tract

Concentrations of Cu, Fe, Zn, Ca, and phytate were measured in dry-milled corn bran, wheat brans, and soybean hulls prior to being baked in bread and after passage through the human GI tract. Significant changes in mineral concentrations in the retrieved remnants compared to the starting materials were as follows: Cu, Fe, and Zn increased by factors of from two to four and Ca increased at least ten-fold in dry milled corn bran; Ca increased and phytate decreased in wheat brans; Zn increased and Fe decreased in soy hulls. These studies show that indigestible remnants of wheat brans in the human colon associate preferentially with calcium and that dry milled corn bran remnants can be loaded with increased concentrations of all four minerals, and especially with calcium. Concentrations of minerals and phytate were significantly greater in whole fecal samples from wheat bran diets than in the corresponding retrieved bran remnants.     

Renal and gastrointestinal potassium excretion in humans: new insight based on new data and review and analysis of published studies

OBJECTIVES: Little is known about the relationship between the renal and gastrointestinal excretion of potassium in humans. This information is important in light of strong associations of potassium intake with hypertension and occlusive stroke. METHODS: We determined the relationship between fecal and urinary excretion of potassium under both fixed and variable potassium intakes using our unpublished archival data and published data of others. Twenty-five subjects were evaluated. RESULTS: On a fixed, low oral potassium intake (61.2 +/- 4.7 mmol/day; mean +/- SD), there was an inverse relationship between fecal and urinary potassium excretion (r = -0.66, p = 0.040). In studies in which potassium intake varied between 61-135 mmol/day, fecal and urinary potassium excretions were positively correlated (r = 0.58, p = 0.024). Considerable within-and-between-subject variation was observed in the relationship between fecal and urinary potassium excretion. CONCLUSIONS: Inter-individual variation in fecal potassium excretion may arise from both variation in dietary potassium intake and intrinsic individual differences in the renal versus gastrointestinal handling of potassium.     

Zinc, iron and phytic acid levels of some popular foods consumed by rural children in Sri Lanka

Zinc (Zn) and iron (Fe) deficiencies may prevail in populations dependent on cereal-based diets containing few animal products. The contribution of Zn and Fe from foods of preschool children of a hill country village in Sri Lanka, is discussed as it is known that the presence of phytic acid (PA) in the diet limits bioavailability of micronutrients. The Zn, Fe and PA contents of cereal-based (rice or wheat flour) composite meals (n=12), wheat flour-based products (n=5), pulses used as staples, snacks or accompaniments (n=6) and other miscellaneous accompaniments (n=4) were determined. Additionally, 20 rice and 3 paddy varieties consumed were also analysed. Although the Zn and Fe levels were reasonable in the composite meals, the PA to Zn molar ratios (5–43) were relatively high, in a majority of meals. Composite meals containing wheat flour (refined) had lower PA levels (<6 mg/100 g) in the absence of pulses and scraped coconut, than rice meals. All rice varieties were partially polished but the PA to Zn molar ratios varied. The major contributors of PA appeared to be soy-textured vegetable protein, all types of jak fruit and scraped coconut kernel. Potable water was a poor source of Zn and Fe. These diets could potentially lead to marginal Zn and Fe deficiencies, and dietary diversification and counselling would be beneficial.     

Long term memory deficits in adult rats due to postnatal malnutrition

Rats who suffered zinc deficiency in early infancy were significantly retarded in the development of their long term memory. Other rats who suffered undernutrition during the same time period did not suffer impaired memory. It was hypothesized that zinc deficiency interfered with the normal development of the brain structures which are necessary for mediating long term memory.     

Leukocytic endogenous mediator in Crohn's disease.

Reduced concentrations of plasma zinc associated with elevated levels of serum leukocytic endogenous mediator activity were found in 17 patients hospitalized with acute exacerbation of Crohn's disease. Neither the decrease in plasma zinc nor the increase in leukocytic endogenous activator activity in nine outpatients with quiescent disease was significant. Leukocytic endogenous mediator activity may be increased in inflammatory conditions as well as in microbial infections. Although zinc deficiency may be common in patients with Crohn's disease, exclusive reliance on circulating zinc levels to assess zinc nutriture in active Crohn's disease may be misleading.