Biomedical subjects

C Kies

Publications and source records attributed to C Kies.

At least 37 records · Page 2Linked to original sources

PubMed1989

Copper absorption as affected by supplemental calcium, magnesium, manganese, selenium and potassium.

Effects of feeding supplements of calcium, magnesium, manganese, selenium and potassium on dietary copper bioavailability of humans were investigated. Results indicated that the calcium supplements depressed fecal copper losses and improved body copper retention as did potassium supplements. Magnesium and selenium supplementation of diets resulted in increased apparent fecal losses of copper while no effect of manganese supplementation was found. It may be that the unexpected positive effect of calcium on copper utilization was due to its neutralizing effect on the relatively high level of ascorbic acid provided by the constant background diet. Ascorbic acid is known to inhibit the absorption of copper.

Animals↗

PubMed1989

Inhibitors of copper bioutilization: fiber, lead, phytate and tannins.

Considerable evidence suggests that copper intakes of Americans have declined in recent years to levels that might be considered seriously low. Under such conditions, other dietary factors which inhibit copper utilization might be of concern since otherwise marginally adequate copper diets might be made copper deficient. A large number of mineral nutrients have been found to interact with copper. Non-nutrient substances in food also may affect copper utilization. Evidence suggesting that lead, certain kinds of dietary fiber, phytates and tannins inhibit copper utilization are reviewed in this paper.

Animals↗

PubMed1985

Non-soluble dietary fiber effects on lipid absorption and blood serum lipid patterns.

Generalized effects of dietary fiber on lipid absorption and blood serum lipid patterns of humans have not been defined and may not even exist. The term dietary fiber covers a wide variety of materials with different chemical and physical characteristics. The ability of pectins and mucilages, often classed as soluble fibers, to lower blood and liver lipids has been demonstrated repeatedly and consistently. However, demonstrated hypolipidemic effects of feeding such non-soluble fibers as cellulose, hemicellulose and bran are by no means consistent. On the basis of pooled data, it appears that hypolipidemic response or non-response of humans to inclusion of non-soluble fibers in diets is in part related to the degree of fecal bulking as a result of in vitro water holding capacity and in part related to pre-study blood serum lipid levels of the individual subjects.

Cholesterol↗

PubMed1979

Effect of dietary fiber on copper, zinc, and magnesium utilization by adolescent boys.

The effect of three dietary fibers on zinc, copper, and magnesium utilization by adolescent boys was studied. The 21-day study was divided into a 2-day introductory nitrogen depletion period, a 3-day adjustment period, and a four 4-day randomly arranged experimental period. During the four experimental periods, the eight adolescent male subjects received a basal diet plus 14.2 g supplements of cellulose, hemicellulose, or pectin. All subjects received all experimental diets. Zinc, copper, and magnesium contents of food, urine and blood serum were measured by atomic absorption spectrophotometry. Relatively small changes in urinary excretion or in blood serum contents of these minerals were found that could be attributed to dietary fiber supplementation. Statistically significant changes in fecal mineral loss were demonstrated. While receiving the basal diet alone or plus hemicellulose, cellulose, or pectin, mean fecal zinc contents (milligrams per subject per day) were 9.64, 13.32, 10.26, and 9.63, respectively; mean fecal copper contents (milligrams per subject per day) were 3.78, 5.04, 4.07, and 3.91, respectively; and mean fecal magnesium contents (milligrams per subject per day) were 303.71, 379.20, 325.69, and 278.48, respectively.

Adolescent↗

PubMed1978

Comparative protein quality as measured by human and small animal bioassays of three lines of winter wheat.

Incomplete information on factors contributing to apparent protein quality and to value of food products as sources of protein and how these factors interact necessitate the use of bioassay procedures. Ideally bioassay procedures should be done using the animal species for which the protein is intended. Practical considerations dictate the use of small animal bioassay rather than human bioassays for routine use in protein product evaluation. To be of real value for routine use in protein product evaluation. To be of real value for assays of food products designed for human use, animal bioassays must accurately predict human performance. Surprisingly little information is available on this topic. In the current project three Nebraska winter wheats of similar genetic backgrounds were evaluated for protein value and for value of the wheats as sources of proteins. Chemical, weanling mouse, adult human and growing human bioassay techniques were employed. Rankings of the grains were similar regardless of species used for protein quality evaluations. Similar rankings were found regardless of species used for protein quality/quantity evaluations. However, ranking varied between methods designed to evaluate protein quality and those designed to measure protein quality/quantity interrelationships. The results stress the importance of matching appropriate methodology with information desired. In a latter project, wheats of dissimilar genetic background were not as uniformily evaluated. This suggests that other factors known to affect protein quality and value were more variable in these wheats.

Animals↗

PubMed1978

Urea as a dietary supplement for humans.

Use of urea as a nonprotein supplement in the feeding of beef cattle and other ruminant animals is a technique of practical application. Urea has also been used in human feeding studies. Its early employment was that of an added source of amino nitrogen in studies designed to determine minimum requirements of the essential amino acid. Later studies suggested that it's inclusion in diet containing sub-optimal amounts of protein supplied by various food product could result in the establishment of apparent improvement in protein nutriture. Other studies indicate that urea is not unique in this ability but is only one of many possible sources of amino nitrogen and is actually one of the least effective. Known and potential hazzards definitely prohibit the use of urea supplements to food products other than in research or clinical laboratories at the present time.

Adolescent↗

PubMed1978

Urinary ascorbic acid excretion in the human as affected by dietary fiber and zinc.

The objective of the project was to study the effect of dietary pectin, cellulose, hemicellulose, and zinc on human urinary excretion of ascorbic acid. The project consisted of two 33-day controlled feeding studies involving a total of 19 adult men and women normal health. Within each study all subjects received all experimental treatments. In study A during the four 7-day experimental periods the ground peanut based diets were varied as follows: no supplement, 14.2 g of hemicellulose supplement, 14.2 g of cellulose supplement, or 14.2 g of pectin supplement per subject per day. Mean urinary excretion of ascorbic acid by subjects while receiving these supplements were 26.10, 32.27, 26.27, or 20.60 mg/day, respectively. In study B during the four 7-day randomly arranged experimental periods, the following alterations were made to the basal diet: supplement of 14.2 g of pectin plus 1.3 g of zinc, 14.2 g of pectin plus 9.3 g of zinc, 4.2 g pectin plus 1.3 g of zinc, and 4.2 g of pectin plus 9.3 g of zinc. Mean urinary ascorbic acid excretion of subjects while receiving these diets were as follows: 20.61, 23.18, 28.07, 18.99. Hemicellulose supplement enhanced urinary excretion of ascorbic acid while pectin and zinc resulted in decreased urinary excretion of this vitamin. Increased urinary excretion of ascorbic acid at constant intake levels is thought usually to be indicative of enhanced absorption or of decreased need.

Adult↗

PubMed1977

Protein nutrition value of urea supplementation of opaque-2 corn for adolescent boys.

The effect of urea supplementation on the protein nutritional value of a plant protein, opaque-2 corn, for adolescent boys was investigated. Seven 12- to 16-year-old boys were subjects for this 23-day study. The mean apparent nitrogen balance when 6 g of nitrogen from corn was fed and when 4 g of nitrogen from urea was added were + 0.63 and + 1.37 g/day, respectively. The improvement in nitrogen balance resulting from the addition of urea to a plant protein source suggested that urea may be used to partially supply the protein needs of growing boys.

Adolescent↗

PubMed1977

Niacin and pantothenic acid excretions of humans fed a low-methionine, plant-based diet.

The addition of a vitamin to a diet of humans has been shown to increase the excretion of that vitamin. The effects of an increase of one vitamin on another have not been investigated. The objective of the current project was to compare the effects of two supplementation patterns on the niacin and pantothenic acid excretion values of humans consuming a peanut butter-based diet. Two groups each received one of two supplementation regimens. One group received niacin, a multi-vitamin, or no supplement. One group received methionine alone, pantothenic acid alone or methionine plus pantothenic acid. The addition of either vitamin resulted in increased excretion of that vitamin. Urinary niacin excretion of the group that received pantothenic acid and/or methionine was greater than that observed with a multi-vitamin or no supplement. Urinary pantothenic acid excretion was suppressed when niacin was a supplement. Urinary pantothenic acid excretion of the methionine supplement group was greater than the excretion of the groups which received either niacin or multi-vitamin supplements. These data suggest some possible dangers in indiscriminate supplementation of food products.

Adult↗

PubMed1975

Comparative value of L-, and D-methionine supplementation of an oat-based diet for humans.

Total sulfur-containing amino acids have been found to be the first limiting amino acid in several foods in comparison with human amino acid requirements. Addition of methionine in appropriate amounts to these foods might be expected to improve protein value. Economically, DL-methionine would be preferable to L-methionine for this purpose. However, the comparative tuilization of L- DL-, and D-methionine is unclear. The objective of the current project was to compare the effectiveness of L-, DL-, and D-methionine supplementation of diets based on a food product known to be low in methionine value for human subjects. "Instant" oatmeal was fed to adult subjects to provide 4.0 g of nitrogen/day. In randomly arranged periods, these diets were supplemented with L-, DL-, or D-methionine at two levels (0.58 and 1.16 g of methionine/day). An unsupplemented diet was used in a control period. Diets were adequate in vitamins, minerals, and energy. Mean nitrogen balances of subjects while receiving the L-methionine supplements at the 0.58 and 1.16 g levels were minus0.10 and +0.06 g of nitrogen, respectively. At similar levels of DL-methionine supplementation, nitrogen balances were minus0.12 and minus0.15 g of nitrogen, respectively, and minus0.24 and minus0.18 g of nitrogen with D-methionine supplementation. The mean nitrogen balance when no supplement was used was minus0.22 g of nitrogen. Thus, D-methionine is seemingly poorly utilized by the human. Urinary methionine excretion data supported these results.

Adolescent↗

PubMed1975

Nutritional and metabolic studies in humans with 1,3-butanediol.

Three studies of the role of 1,3-butanediol (BD) in human nutrition are described. Isocaloric substitution of BD for starch in the diets of volunteers caused less negative nitrogen balance. Ingestion of urea also decreased negative nitrogen balance, and the effect of BD plus urea in the diets seemed to be additive. No effects were detected on many blood parameters measured during and after the study, except that BD feeding decreased blood glucose significantly. 1,3-Butanediol was shown to be a nontoxic metabolite providing a source of calories for human nutrition. In a second study, ingestion of BD was shown to cause slight increases in serum insulin and growth hormone concentrations in the fasting state. We next studied the effects of prior ingestion of BD on serum insulin, growth hormone, glucose, and lipids during glucose tolerance tests. No significant differences in these parameters were noted when prior ingestion of sucrose or an isocaloric quantity of BD were compared. Possible mechanisms whereby ingestion of BD spared nitrogen and caused decreased blood glucose are discussed.

Blood Glucose↗

PubMed1973