Biomedical subjects

M A Kenney

Publications and source records attributed to M A Kenney.

33 records · Page 2Linked to original sources

PubMed1986

Nutrients supplied by food groups in diets of teenaged girls.

Sources of nutrients were determined in diets of teenaged girls, a group generally thought to be at nutritional risk. This study of Southern adolescent girls of two races examines intakes of energy, energy-yielding nutrients, vitamins, minerals, and other components of various food groups. Effects of race, age, place of residence, and per capita income on nutrients furnished by food groups were determined from two 24-hour dietary recalls from each of 1,195 girls, aged 12, 14, or 16. Of the food groups examined, foods of low nutrient density provided the most energy, fat, and carbohydrate. The meat group provided the most protein. Dairy products, which supplied the largest amounts of six vitamins and minerals of any food group, were used less by black, rural, or older teenagers than by white, urban, or younger girls. Blacks obtained more vitamin A from vegetables and more thiamin from meat than whites. Amounts of meat, starchy, and low-nutrient-density subgroups also varied with race, age, and/or place of residence. As income increased, consumption of starches (especially breakfast cereals) and eggs decreased and that of fruit increased.

Adolescent↗

PubMed1985

Vitamin B-6 status of southern adolescent girls.

The vitamin B-6 status of 583 white and black adolescent girls living in Alabama, Arkansas, North Carolina, Oklahoma, and Virginia was assessed using the parameters coenzyme stimulation of erythrocyte alanine aminotransferase activities and dietary intakes of the vitamin. The sample included 382 white and 201 black girls who were 12, 14, or 16 years of age; the sample was also divided into low, medium, and high per capita income groups. The height and weight measurements of the subjects were within normal ranges. The mean estimated daily vitamin B-6 intake of the girls from food sources was 1.20 mg daily, as indicated by evaluation of data obtained via two nonsequential 24-hour food recalls; about half of the subjects reported consuming less than 66% of the Recommended Dietary Allowance for the vitamin. Approximately 20% of the girls had marginal vitamin B-6 status and 13%, deficient status, as indicated by coenzyme stimulation values. Coenzyme stimulation and dietary values of the race, age, and income groups were similar. Vitamin B-6 inadequacy appears to be fairly prevalent among white and black southern adolescent girls.

Adolescent↗

PubMed1984

Erythrocyte and dietary zinc in adolescent females.

Erythrocyte zinc has been suggested as an index of zinc status. This study was undertaken to investigate the possible relationships of erythrocyte zinc concentration to age, physical maturity, and zinc intake of teenage girls of two races. Dietary zinc was calculated from two 1-day food recalls, and erythrocyte zinc was determined for over three hundred 12-, 14- and 16-yr-old girls in Oklahoma and Virginia. Erythrocyte zinc concentration increased and the intake of zinc from the diet decreased after attainment of menarche. Among girls of the same menarcheal state, age was not related to zinc intake, but concentration of zinc in erythrocytes increased with each 2-yr age increment in those that were past menarche. Results did not show a direct relationship of erythrocyte zinc values to calculated intakes of zinc by adolescent females. Black and white races did not differ in either zinc intake or red cell zinc content.

Adolescent↗

PubMed1984

Nutrient intakes of female adolescents from eight southern states.

Nutrient intakes were calculated from two 24-hour recalls for 1,247 adolescent black and white girls. Whites consumed more vitamins E, C, and B-12, niacin, folacin, calcium, phosphorus, magnesium, and zinc and had higher intakes per 1,000 kcal of those nutrients, protein, vitamin D, and iron than blacks. Intakes of calcium (whites) and magnesium (both races) decreased with age. Urban girls consumed more energy and magnesium than rural ones. Folacin intake increased with income. Folacin intakes were most frequently below 67% RDAs, followed by intakes of iodine, vitamin D, iron, calcium, vitamin B-6, zinc, magnesium, and vitamin A. The majority of diets met or exceeded RDAs for protein, vitamins E, C, and B-12, riboflavin, and thiamin. Intakes are reported for most nutrients for which safe ranges have been set.

Adolescent↗

PubMed1983

The iron status of Black and white female adolescents from eight Southern states.

Hb, hematocrit, plasma iron, and transferrin saturation were measured in approximately 1000 girls aged 12, 14, or 16 yr in eight southern states. The iron status parameters did not differ significantly among the three age groupings or between menstruating and nonmenstruating girls. Blacks had significantly lower mean Hb (p less than 0.0001), hematocrit (p less than 0.0001), and transferrin saturation (p less than 0.05) levels than whites and a greater proportion of Blacks exhibited low Hb (p less than 0.05) and low hematocrit levels (p less than 0.01). Adjusting for dietary iron intakes and per capita income levels did not adequately account for significant race differences for iron status parameters. These findings support the contention that genetic as well as environmental factors are responsible for the frequently reported Black-white differences in Hb and hematocrit levels.

Adolescent↗

PubMed1983

Copper content of tea.

Published data for copper content of tea are contradictory. To resolve the issue, various brands and flavors of four different types of tea were prepared in two kinds of containers and analyzed for copper. Copper concentrations averaged from 0.14 p.p.m. for herbal and instant teas to 0.19 for brewed regular tea, plain or flavored. All concentrations were well below a previously reported value for tea as a beverage.

Copper↗

PubMed1975

Depressed immune response in the magnesium-deficient rat.

The effects of dietary magnesium on growth, food efficiency, organ development, splenic nucleic acids, and serum antibody were studied in two experiments with male Wistar rats. Diets containing 30% protein from casein were fed ad libitum. Rats were immunized intravenously with sheep red blood cells. Blood was obtained 5 and 9 days after immunization. In experiment 1, a group of weanling rats was fed 10 ppm Mg for 8 days, followed by 142 ppm for 37 days. Group 2 (controls) was fed 480 ppm Mg for 45 days. Group 1 weighed less but had larger spleens, kidneys, and testes relative to body size than did group 2. Nucleic acids per gram spleen were similar in both groups as were serum gamma-globulin and its 19S and 7S components. Antibody log titers for group 1 were 45 and 65% of control agglutinin levels and 44 and 80% of control hemolysin values on days 5 and 9, respectively. In experiment 2,200-g rats were fed 10 (group 3) or 480 ppm (group 4) Mg for 38 days. Most effects of the 10 ppm Mg diet were similar to those seen in magnesium deficiency in experiment 1. Antibody titers for group 3 were 30 and 25% of control agglutinin and 43 and 53% of control hemolysin values on days 5 and 9, respectively. Total serum gamma-globulin and its 19S fraction were similar in both groups, while the 7S fraction of group 3 was only 64% of the control value.

Animals↗

PubMed1973