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M M Polansky

Publications and source records attributed to M M Polansky.

35 records · Page 2Linked to original sources
PubMed1988

Exercise effects on chromium excretion of trained and untrained men consuming a constant diet.

Chromium excretion of eight trained and five sedentary men was determined on rest days and after exercise to exhaustion at 90% of maximum O2 consumption (VO2max) to determine if degree of physical fitness affects urinary Cr losses. Subjects were fed a constant daily diet containing approximately 9 micrograms Cr/1,000 kcal. VO2max of the trained runners was in the good or above range based on their age and that of the sedentary subjects was average or below. While consuming the control diet, basal urinary Cr excretion of subjects who exercise regularly was significantly lower than that of the sedentary control subjects, 0.09 +/- 0.01 and 0.21 +/- 0.03 microgram/day (mean +/- SE), respectively. When subjects consumed self-chosen diets, basal urinary Cr excretion of the trained subjects was also significantly lower than that of the untrained subjects. Daily urinary Cr excretion of trained subjects was significantly higher on the day of a single exercise bout at 90% VO2max compared with nonexercise days, 0.12 +/- 0.02 and 0.09 +/- 0.01 microgram/day, respectively. Urinary Cr excretion of sedentary subjects was not altered after controlled exercise. These data demonstrate that basal urinary Cr excretion and excretion in response to exercise are related to VO2max and therefore degree of physical fitness.

Adult↗
PubMed1987

Effects of supplemental chromium on patients with symptoms of reactive hypoglycemia.

To determine if chromium (Cr) is involved in hypoglycemia, eight female patients with symptoms of hypoglycemia were supplemented with 200 micrograms of Cr as chromic chloride for three months in a double-blind crossover experimental design study. Chromium supplementation alleviated the hypoglycemic symptoms and significantly raised the minimum serum glucose values observed two to four hours following a glucose load. Insulin binding to red blood cells and insulin receptor number also improved significantly during Cr supplementation. These data suggest that impaired Cr nutrition and/or metabolism may be a factor in the etiology of hypoglycemia.

Adult↗
PubMed1985

Serum chromium of human subjects: effects of chromium supplementation and glucose.

Seventy-six adult subjects, 48 males and 28 females, were given placebo or 200 micrograms Cr in the form of chromic chloride in a double-blind crossover study, with 3-month experimental periods, to determine basal serum Cr levels and the effects of Cr supplementation on serum Cr and related variables. Basal serum Cr determined by graphite furnace atomic absorption for all subjects was 0.13 +/- 0.02 ng/ml (mean +/- SEM), and increased significantly to 0.38 +/- 0.02 ng/ml following 3 months of Cr supplementation. There were no significant differences in the serum Cr values for males and females. Serum Cr 90 min following a glucose load (1 g per kg body wt) was not significantly different from fasting during either the placebo or Cr supplementation periods. These data demonstrate that serum Cr increased significantly following Cr supplementation and is a reflection of Cr intake, but serum Cr concentration, even that following a glucose load, does not appear to be a meaningful indicator of Cr status.

Adult↗
PubMed1983

Chromium supplementation of human subjects: effects on glucose, insulin, and lipid variables.

Seventy-six normal, free-living subjects were given supplements of 200 micrograms chromium (Cr) in the form of chromic chloride or a placebo in a double-blind crossover study with 3-month experimental periods. Twenty of the 76 subjects had serum glucose concentrations greater than or equal to 100 mg/dL 90 minutes after a glucose challenge (1 g glucose per kilogram of body weight). Chromium supplementation significantly decreased (P less than 0.05) the 90-minute glucose concentration of these subjects from 135 +/- 9 to 116 +/- 11 mg/dL; fasting glucose concentrations also decreased significantly. The 90-minute serum glucose levels of the 35 subjects with glucose concentrations less than the fasting serum glucose level were increased significantly by Cr supplementation, from 71 +/- 1 to 81 +/- 4 mg/dL. Fasting and 90-minute serum glucose concentrations of the remaining subjects who displayed 90-minute glucose concentrations greater than fasting levels but less than 100 mg/dL were not affected by Cr supplementation. In this study, immunoreactive serum insulin concentration, body weight, lipids, and other selected clinical variables did not change significantly during Cr supplementation. These data demonstrate that Cr supplementation decreases the serum glucose levels of subjects with 90-minute glucose concentrations greater than or equal to 100 mg/dL following a glucose challenge, increases serum glucose levels of subjects with 90-minute glucose concentrations less than fasting levels, and has no effect on the serum glucose levels of subjects with 90-minute glucose values similar to but greater than fasting levels.

Adult↗
PubMed1983

Effects of chromium supplementation on urinary Cr excretion of human subjects and correlation of Cr excretion with selected clinical parameters.

Daily urinary chromium (Cr) excretion of 15 healthy free-living female subjects was 0.20 +/- 0.03 microgram (mean +/- SEM) and nearly identical for 27 male subjects, 0.17 +/- 0.02 microgram. Minimum Cr absorption calculated from urinary Cr excretion was about 0.4 percent. Increasing intake fivefold by Cr supplementation led to a nearly fivefold increase in Cr excretion suggesting that the extent of absorption of supplemental inorganic chromium was similar to that from normal dietary sources. Correlations between 24-hour Cr excretion and urine volume, age, total creatinine and body weight were not found. Urinary Cr concentration of samples obtained following a morning void correlated with creatinine and Cr concentration following a glucose challenge but not with serum glucose, insulin, lipid parameters, age or body weight. Similar results were obtained for urine samples obtained from subjects during Cr supplementation. These results suggest that urinary Cr excretion does not appear to be a meaningful indicator of Cr status but is a meaningful indicator of Cr intake and that the absorption of supplemental inorganic Cr was similar to that of Cr from normal dietary sources.

Adult↗
PubMed1982

Urinary chromium excretion of human subjects: effects of chromium supplementation and glucose loading.

The utilization of inorganic chromium by free-living human subjects was studied in 76 volunteers (male, 48; female, 28) who were supplemented with 200 micrograms of inorganic chromium as chromic chloride or a placebo tablet for 3 months in a double-blind, cross-over experiment. For all subjects, initial mean +/- SEM urinary chromium (Cr) level was 0.20 +/- 0.01 (range, 0.05 to 0.58) ng/ml and did not differ by sex. Initial chromium/creatinine ratio (Cr/Ct) was 0.15 +/- 0.01 (range 0.03 to 0.36) ng Cr/mg creatinine for females and was significantly lower, 0.10 +/- 0.01 (range 0.03 to 0.36) for males. Mean urinary Cr level increased to 1.0 +/- 0.12 after 2 and to 1.13 +/- 0.08 ng/ml after 3 months' supplementation. The Cr/Ct ratio increased to 0.69 +/- 0.10 for females and to 0.50 +/- 0.04 for males after 2 months' supplementation; values were similar after 3 months. An increase in urinary Cr excretion in response to a glucose load was demonstrated for nonsupplemented normal free-living subjects but not for subjects supplemented daily with trivalent chromium. Urinary Cr excretion after a glucose challenge was not predictable and did not depend on Cr status.

Adult↗
PubMed1982

Effect of exercise (running) on serum glucose, insulin, glucagon, and chromium excretion.

Chromium is involved in normal glucose metabolism. To test whether chromium is also associated with the exercise-induced increases in glucose utilization, urinary chromium excretion, serum glucose, insulin, and glucagon of nine male runners (23-46 yr) were evaluated. Blood samples were taken prior to, immediately following, and 2 h after a strenuous 6-mile run. Urine samples were also taken at these times, and total daily urine collections were made the day of the run and the following day. Mean serum glucose for all runners immediately after running was 185 +/- 19 mg/dl compared with 90 +/- 1 mg/dl (mean +/- SE) prior to running. Mean serum glucagon immediately after running was significantly elevated compared with that observed prior to or 2 h after running; serum insulin levels were not altered significantly. Mean urinary chromium concentration was increased nearly five-fold 2 h after running; similar results were obtained when chromium concentration was expressed per mg of creatinine. Total daily urinary Cr excretion was approximately two times higher the day of running compared with the following nonrun day. Daily urinary excretion of sodium, potassium, and calcium were measured to determine if exercise had a general nonspecific effect on renal function; daily urinary excretion of these was not changed by exercise. These data demonstrate that accompanying the exercise-induced changes associated with increased glucose utilization, there is a significant increase in chromium excretion.

Adult↗
PubMed1979

Metal-free housing units for trace element studies in rats.

Metal-free housing units fabricated from clear plastic and polystyrene egg crate panels were used to house rats for studies involving trace elements. The cages did not require bedding, were well ventilated and fitted into commercially available cage racks. Modifications of the basic design were made to provide both maternity and metabolism cages.

Animals↗
PubMedDate not supplied

Dietary chromium intake. Freely chosen diets, institutional diet, and individual foods.

Chromium content of 22 daily diets, designed by nutritionists to be well-balanced, ranged from 8.4 to 23.7 micrograms/1000 cal with a mean +/- SEM chromium content of 13.4 +/- 1.1 micrograms/1000 cal. Most diary products are low in chromium and provide less than 0.6 micrograms/serving. Meats, poultry, and fish are also low in chromium, providing 2 micrograms of chromium or less per serving. Chromium contents of grain products, fruits, and vegetables vary widely, with some foods providing greater than 20 micrograms/serving. In summary, chromium content of individual foods varies, and is dependent upon chromium introduced in the growing, transport, processing, and fortification of the food. Even well-balanced diets may contain suboptimal levels of dietary chromium.

Adult↗