Plasma pyridoxal phosphate concentrations and coenzyme stimulation of erythrocyte alanine aminotransferase activities of white and black adolescent girls.

The vitamin B6 status of 96 white and 90 black female adolescents was assessed utilizing plasma pyridoxal phosphate concentrations, coenzyme stimulation of erythrocyte alanine aminotransferase activities, and vitamin B6 intakes. These values were similar for the two race and three age groups. Fifty-eight percent of the girls reported consuming less than 0.02 mg vitamin B6/g protein daily. The mean coenzyme stimulation and pyridoxal phosphate values of the subjects were 13.5% and 45.2 nM. Coenzyme stimulation values greater than 25% were observed in 18% of the girls and values between 16 and 25%, in 23%. Plasma pyridoxal phosphate concentrations less than 34.4 nM were observed in 26% of the girls and values from 34.4 to 40.5 nM, in 14%. Vitamin B6 inadequacy was prevalent among white and black southern adolescent girls participating in this study as indicated by plasma pyridoxal phosphate concentrations, coenzyme stimulation of erythrocyte alanine aminotransferase activities, and vitamin B6 intakes.

Lung function and treadmill performance of smoking and nonsmoking males receiving ascorbic acid supplements.

Twelve cigarette smoking and 10 nonsmoking healthy human volunteers, 25 to 38 yr of age, performed lung function and treadmill performance tests over two periods of 3 wk duration while taking either ascorbic acid (300 mg daily) or placebo tablets in a cross-over design. The two exercise periods were separated by a one-month inactive phase. Tablets were administered in a random, double-blind manner. Plasma vitamin C levels were significantly increased after 3 wk of ascorbic acid supplementation in both smokers and nonsmokers as compared to initial levels in the same subjects. No differences between ascorbic acid and placebo treatments of smokers and nonsmokers were observed for 1-s forced expiratory volume, forced vital capacity, 1-s forced expiratory percent, resting heart rate, resting and postexercise systolic and diastolic blood pressures, treadmill workload, postexercise blood lactic acid, and ventilation measurements. The postexercise systolic blood pressure values of the nonsmokers were lower, although not quite significantly, after the ascorbic acid treatment than after the placebo. The 300-mg ascorbic acid supplement appeared to have little effect on the lung function and physical performance of healthy smoking and nonsmoking males.

Vitamin B6 status of a group of preschool children.

The vitamin B6 status of 35 preschool males and females was evaluated using plasma pyridoxal phosphate levels. The kilocalorie, protein, and vitamin B6 intakes were also estimated. Height and weight values of the three and four year old volunteers were within normal ranges. Seventeen percent of the children had estimated vitamin B6 intakes less than 2/3 of RDA. The estimated B6 intakes and plasma pyridoxal phosphate levels of children who took vitamin supplements were significantly higher than values for subjects not taking supplements. The plasma pyridoxal phosphate levels of children reportedly consuming less than the RDA for vitamin B6 were significantly lower than those of subjects consuming higher levels. Of the children 9% seemed to have inadequate vitamin B6 status as indicated by their having plasma pyridoxal phosphate levels below 8.5 ng/ml.

Plasma pyridoxal 5'-phosphate concentrations in obese and nonobese black women residing near Petersburg, VA.

The vitamin B-6 status of 15 obese and 15 nonobese black women aged 21-51 y who were not taking vitamin supplements was assessed by using plasma pyridoxal 5'-phosphate (PLP) measurements. Ages, heights, and ideal body weights of the two groups were similar as were reported energy, protein, and vitamin B-6 intakes obtained by using 24-h intake data collected on two nonconsecutive days separated by at least 1 wk. The reported vitamin B-6 intakes were 1.18 +/- 0.44 mg/d (means +/- SD). Plasma PLP levels in the obese and nonobese black women were similar; these levels were also similar to those observed previously for white obese and nonobese women having similar physical characteristics. All subjects had plasma PLP levels indicative of adequate status with one possible exception. Obesity did not affect the plasma PLP levels in these black women.

Riboflavin and thiamin status and birth outcome as a function of maternal aerobic exercise.

Twenty-eight healthy pregnant women taking vitamin-mineral supplements served as controls or participated in a walking program from 22 to 30 wk gestation to determine the effects of aerobic exercise on maternal riboflavin and thiamin status and birth outcome. Aerobic capacity was evaluated by heart rate (HR) and relative oxygen consumption (RVO2) during submaximal treadmill walking. HR responses at 30 wk gestation were significantly lower for walking (n = 18) than nonwalking (n = 10) groups at 2 and 4 min of exercise. RVO2 for walkers decreased significantly from 22 to 30 wk at 2, 4, and 6 min. Riboflavin and thiamin status, determined by erythrocyte glutathione reductase and transketolase activity coefficients, was adequate for 86 and 96% of the subjects, respectively. Birth-outcome measurements were similar for all subjects. Participation in the walking program slightly improved aerobic capacity without affecting riboflavin or thiamin status or birth outcome in pregnant women taking vitamin-mineral supplements.

Erythrocyte and plasma B-6 vitamer concentrations of long-term tobacco smokers, chewers, and nonusers.

Erythrocyte and plasma B-6 vitamer concentrations were determined in males aged 25-55 y who were long-term smokers, chewers, or nonusers. Tobacco users had either smoked (n = 23) or chewed (n = 11) for > 15 y; nonusers (n = 11) had never smoked or chewed. All subjects had normal hematocrit values. Food energy, protein, and vitamin B-6 intakes of the three groups of subjects were not significantly different. All subjects had fasting plasma pyridoxal-5'-phosphate (PLP) concentrations indicative of adequacy. Erythrocyte B-6 vitamer and 4-pyridoxic acid (4-PA) concentrations of all three groups were not significantly different. Nonusers had significantly higher plasma PLP concentrations than did smokers, whereas PLP concentrations of chewers were intermediate between the two groups. Chewers had significantly higher concentrations of plasma pyridoxamine-5'-phosphate (PMP) than other groups. Plasma pyridoxal, pyridoxine, pyridoxamine, and 4-PA concentrations of the three groups were not significantly different. Differences in some B-6 vitamer concentrations in plasma but not in erythrocytes were observed between tobacco users and nonusers.

Maternal aerobic exercise and vitamin B-6 status.

Effects of an aerobic walking program during gestational weeks 22-30 on vitamin B-6 status and birth outcome were studied in 28 healthy pregnant women, aged 21-36 y, receiving vitamin-mineral supplements. Mean daily vitamin B-6 intake, excluding a 10-mg supplement, was 1.81 mg. Subjects in the walking (n = 18) and nonwalking (n = 10) groups had similar microbiologically assessed plasma total vitamin B-6 levels and radioenzymatically assessed plasma pyridoxal phosphate concentrations. One walker at 22 wk and at 30 wk and a second walker at 30 wk had plasma total vitamin B-6 concentrations in the low-normal range; the same was true for plasma pyridoxal phosphate levels except that the 30-wk value for the walker who was low at 22 wk was missing. Birth-outcome measurements were similar for both groups. Participation in the walking program slightly improved aerobic fitness without affecting vitamin B-6 status or birth outcome in pregnant women taking vitamin-mineral supplements.

Plasma pyridoxal phosphate concentrations of men fed different levels of vitamin B-6.

The vitamin B-6 status of 12 white, 3 black, and 7 men of other races was evaluated utilizing plasma pyridoxal phosphate concentrations after the males had been on controlled diets for 8 wk. The diets contained averages of 1.22-1.67 mg/d vitamin B-6 as calculated from food composition tables. The actual mean vitamin B-6 content of these diets as analyzed with Saccharomyces uvarum was 0.75-0.98 mg/d; the mean daily protein intakes were 80.8-84.5 g. All subjects had plasma pyridoxal phosphate concentrations (67.6-125.8 nmol/L) well within the normal range; the values of the different race and dietary groups were similar. Vitamin B-6 requirements were satisfied by the consumption of diets analyzed to contain means of 0.75-0.98 mg/d of the vitamin as demonstrated by plasma pyridoxal phosphate levels indicative of adequate status. Dietary vitamin B-6 intakes should be determined by actual analyses when requirements are being determined.

Effect of coarse wheat bran fiber and exercise on plasma lipids and lipoproteins in moderately overweight men.

The effects of the American Association of Cereal Chemists coarse wheat bran fiber and exercise were evaluated in 20 males, aged 24 to 35 yr, and at least 10% above ideal weight. Thirteen of the subjects participated in a 4 mile walk-jog run program 3 times weekly. In a cross-over design with diets switched midway through the experiment, both the exercising and sedentary groups consumed isocaloric amounts of either white bread or white bread containing wheat bran (0.5 g/kg body weight). Plasma total and lipoprotein cholesterol and triglycerides, body weights, and percentage body fats were determined at 0, 6, and 12 wk. No consistent effects were observed as a result of the wheat bran feeding on any of the parameters measured. Exercise training tended to decrease body weights and percentage body fats, and was associated with significantly increased (p less than 0.05) plasma high-density lipoprotein cholesterol levels and high-density lipoprotein cholesterol to low-density lipoprotein cholesterol ratios. After a rise in triglycerides at wk 6, a significant decline (p less than 0.05) back to base-line values was observed at wk 12 for the exercised subjects.

Vitamin B-6 content of selected foods served in dining halls.

Roast beef and green beans lost significant quantities of vitamin B-6 during institutional cooking and holding procedures; some was leached into juice and pot liquor. Whole baking potatoes lost smaller quantities of the vitamin during these procedures. A mean of 60% of the vitamin that was present in the foods before cooking was actually served. More vitamin B-6 will be retained if cooking and holding times are held to a minimum.

Vitamin E status of adolescent girls.

The vitamin E status of 88 adolescent girls living in the western Virginia area was measured. About 12% of the subjects had marginal to low vitamin E status, as indicated by plasma total tocopherol levels. Approximately 12% reported consuming less than two-thirds of the RDA for vitamin E. Plasma total tocopherol levels were not significantly correlated with reported vitamin E intakes.

Vitamin E, vitamin B-6, vitamin B-12, and folate status of gastric bypass surgery patients.

The vitamin E, vitamin B-6, vitamin B-12, and folate status of 22 gastric bypass subjects aged 23 to 60 years was evaluated before surgery and at 6 and 12 months after surgery. Before surgery, 77% of subjects had adequate plasma vitamin E levels; 36%, adequate plasma pyridoxal phosphate levels; 100%, adequate plasma vitamin B-12 levels; and 45%, adequate plasma folate levels. The food intake of all subjects was sharply reduced after surgery. After surgery, subjects were classified into three vitamin supplement groups on the basis of average daily vitamin supplement intake. Subjects taking higher levels of supplements containing the vitamins in question had significantly higher plasma concentrations of the vitamins than those taking low or moderate levels. The mean plasma vitamin values in the moderate supplement group were indicative of adequate status for all vitamins, but plasma vitamin B-12 levels at 12 months post-surgery were significantly lower than pre-surgery levels. In the low supplement group, mean plasma vitamin levels were in or near marginal or deficient ranges. The majority of subjects consuming supplements of vitamin E, vitamin B-6, and folate near the US RDA maintained normal vitamin status. Subjects taking more than 100 micrograms vitamin B-12 daily had adequate vitamin B-12 status. Significant correlations (r = .67 to .94) were observed between vitamin supplement levels and the respective plasma vitamin concentrations.

Longitudinal assessment of vitamin B-6 status in southern adolescent girls.

The vitamin B-6 status of 62 black and 50 white adolescent girls living in Virginia and Alabama was assessed in 1981 and again in 1983, using the parameters coenzyme stimulation of erythrocyte alanine aminotransferase activities and dietary intakes of the vitamin. The subjects were 12 or 14 years old in 1981. The height and weight measurements of the subjects were within normal ranges. The mean daily vitamin B-6 intake of the girls from food was 1.25 mg both years, as estimated by two nonsequential 24-hour food recalls. Approximately half of the girls reported consuming less than 0.02 mg vitamin B-6 per gm protein during both years. Almost half of the girls had coenzyme stimulation values indicative of marginal or deficient status. Coenzyme stimulation and dietary values of the race, age, and income groups were similar. Changes in the status grouping of the girls between the 2 years as reflected by the coenzyme stimulation measurement were associated with changes in their vitamin B-6 intakes in 70% of the cases. Vitamin B-6 inadequacy seems to be prevalent among both black and white adolescent girls.

Nutritional status of white college students in Virginia.

The nutritional status of the fifty men, fifty-three women, and forty-seven women taking oral contraceptives--all white--between the ages of seventeen and twenty-two years--as reflected by height-weight measurements, hemoglobin-hematocrit values, and dietary records, was similar or slightly better than reported by other investigators. Low hemoglobin values were observed in 2 to 4 per cent of these students, and low hematocrits, in 8 to 17 per cent. Similar hemoglobin and hematocrit values were observed in all women, regardless of whether they were taking oral contraceptives. Exercise patterns; use of vitamin-mineral supplements, "pot," alcoholic beverages, special diets; whether subjects ate alone; where subjects ate; snacking; number of meals consumed daily; whether subjects had ever been diagnosed as being anemic; and what subjects thought of their food habits did not affect hemoglobin or hematocrit. Iron intakes of many of the women students were below the allowance.

Dairy product purchases by southern households.

Dairy product purchases of 1,061 southern households in 1972 and 1973 were analyzed. Quantities purchased increased with income. Whites bought more dairy products than blacks. Fluid milks represented approximately three-quarters of the dairy products purchases. Also, from mid-1972 to late-1973, households bought similar quantities of the various fluid milks despite price increases. They did not switch their purchasing practices from fluid milks higher in saturated fat and cholesterol to those that are lower. Dairy product purchases would have contributed significantly to "advised" intakes of calories, protein, calcium, fat, and cholesterol.

Margarine and butter purchases of southern households.

Margarine and butter purchases of 1,061 southern households are reported. These families purchased twelve times as much margarine as butter. Medium-income households, those headed by grammar school-educated persons, households headed by farmers, those with an unemployed homemaker, and white households bought more margarine, on the average, than those in other categories. High-income households and those headed by retired/unemployed persons, on the other hand, generally purchased more butter. In these southern households, margarine purchases would have contributed significantly to "advised" caloric and fat intakes.

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.

Vitamin E status of young women on combined-type oral contraceptives.

Differences in vitamin E status between young Caucasian women using oral contraceptives (OCs) for 1 yr or more and control females were obtained with regard to the following parameters: 1) hemolysis, 2) plasma total tocopherols by spectrophotometric analysis, 3) individual tocopherols by a thin-layer gas-liquid chromatographic (TLC-GLC) technique, and 4) dietary intakes of vitamin E, polyunsaturated and saturated lipids, cholesterol and kilocalories. Ten subjects were on Ortho-Novum- or Norinyl-1/50, 8 on Ortho-Novum- or Norinyl-1/80, and 10 had never taken OCs. Analyses of 24-hr recalls and 7-day dietary records revealed no significant differences among groups for intakes of nutrients listed above. No significant differences among groups were observed from hemolytic values. Plasma total tocopherol concentrations measured by spectrophotometric and TLC-GLC techniques revealed that OC-1/80 subjects had significantly lower values than controls. Marginally inadequate vitamin E status as assessed by the various techniques was observed in approximately one subject in the control and OC-1/50 groups and in 2 of the OC-1/80 women. Large individual variations in vitamin E status were observed for subjects in all groups on similar estimated vitamin E intakes. TLC-GLC measurements of total tocopherols in plasma seemed to be perhaps a more sensitive indicator of vitamin E status of subjects than spectrophotometric analysis of tocopherols.

Carotenoid content, physicochemical, and sensory qualities of deep-fried carrot chips as affected by dehydration/rehydration, antioxidant, and fermentation.

Carrot slices were subjected to one of the following experiments prior to deep-frying: (A) dehydration/rehydration, (B) soaking in different antioxidants, and (C) fermentation with/without blanching. There were no significant differences (P > or = 0.05) in carotenoid contents among carrot chips treated with/without dehydration. Soaking in sodium metabisulfite resulted in the highest carotenoid content and lightness (L), redness (a), and yellowness (b) values among the antioxidant treatments. Fermentation without blanching significantly decreased (P < 0.05) carotenoid content, vitamin A activity, and fat content. Dehydration and fermentation with blanching significantly increased (P < 0.05) the lightness (L), redness (a), and yellowness (b) values of the chips. Dehydration/rehydration, but not antioxidant and fermentation, significantly decreased (P < 0.05) the water activity of the chips. The textural values of carrot chips prepared using sodium metabisulfite, without dehydration and without fermentation, were the lowest among other treatments which suggests the crispiest. Carrot chips prepared using sodium metabisulfite, without dehydration and without fermentation, had the highest carotenoid content and retention, and the highest overall acceptability score.

Riboflavin and niacin concentrations of bison cuts.

We analyzed the riboflavin and niacin contents of individual cuts from clod (triceps brachii), ribeye (longissimus thoracis), top round (semimembranosus), and top sirloin (gluteus medius) from 24 fed bison bulls. The bulls came from producers in the United States and Canada and had consumed concentrate diets plus hay free choice for at least 100 d. The mean riboflavin and niacin concentrations of all of the bison cuts combined were .094 and 1.910 mg/100 g wet weight, respectively. The riboflavin and niacin content values did not differ (P < .05) among the cuts of meat. Cuts from individual bulls were significantly different (P < .05) with regard to both riboflavin and niacin contents. Little variation was observed in riboflavin and niacin content of five bison from the same producer and two bison from another producer. These content values may be used in estimating the riboflavin and niacin content of bison meat.