Nutritional contribution of eggs to American diets

OBJECTIVES

The main purposes of this study were (1) to assess the nutritional significance of eggs in the American diet and (2) to estimate the degree of association between egg consumption and serum cholesterol concentration.

METHODS

Data from the most recent National Health and Nutritional Examination Survey (NHANES III, 1988-94) were utilized to compare the nutritional quality indicators of diets that contained eggs (USDA food grouping system) with those that did not. Nutrient intake (from 24-hour dietary recall), egg intake (from food frequency questionnaire), sociodemographic data and blood cholesterol levels of subjects who met inclusion criteria (n = 27,378) were grouped according to the occurrence and frequency of egg consumption and were analyzed using SUDAAN.

RESULTS

Daily nutrient intake of egg consumers (EC) was significantly greater than that of nonconsumers (NC) for all nutrients studied (except dietary fiber and vitamin B6). Eggs contributed < 10% of daily intake of energy and vitamin B6, 10% to 20% of folate and total, saturated and polyunsaturated fat, and 20% to 30% of vitamins A, E and B12 in EC. Compared to EC, NC had higher rates of inadequate intake (defined by Estimated Average Requirements (EAR) or < 70% Recommended Dietary Allowance (RDA)) for vitamin B12 (10% vs. 21%), vitamin A (16% vs. 21%), vitamin E (14% vs. 22%) and vitamin C (15% vs. 20%). After adjusting for demographic (age, gender and ethnicity) and lifestyle variables (smoking and physical activity), dietary cholesterol was not related to serum cholesterol concentration. People who reported eating > or = 4 eggs/wk had a significantly lower mean serum cholesterol concentration than those who reported eating < or = 1 egg/wk (193 mg/dL vs. 197 mg/dL, p < 0.01). More frequent egg consumption was negatively associated with serum cholesterol concentration (beta = -6.45, p < 0.01).

CONCLUSIONS

In this cross-sectional and population-based study, egg consumption made important nutritional contributions to the American diet and was not associated with high serum cholesterol concentrations.

The Computer Programme “MSU Nutriguide: Asian Indian Foods” is Effective in Assessing Nutrient Intakes of Indian Populations

A nutritional study was conducted on 150 female college students aged 18 to 23 at the Punjab Agricultural University, Ludhiana, India, to evaluate the effectiveness of “MSU Nutriguide: Asian Indian Foods,” a computer programme for assessing nutrient intakes and total energy expenditure (TEE) of the Indian population. A non-significant difference between analysed and calculated values for energy, protein, iron, and ascorbic acid revealed that the intake of the nutrients calculated with the MSU Nutriguide was a correct assessment in most of the subjects. TEE estimation by MSU Nutriguide gives values based on age, height, weight, and four levels of physical activity (sleeping and light, moderate, and heavy activity), whereas prediction equations are based on the body weight of each subject and a single level of activity. Therefore, MSU Nutriguide can be efficiently used to assess the TEE of people in India.

Dieting behavior of Asian college women attending a US university

Dieting behavior, body dissatisfaction, self-esteem, and food intake of 73 Asian women attending a US university were investigated and compared retrospectively with attitudes of 247 US-born female students at the same university. The Asian women reported restrained eating and body dissatisfaction only about half as often as the US women did. In both the Asian and US college women, body dissatisfaction scores were significantly correlated to body mass index and self-esteem scores. Fourteen percent of the Asian women in the restrained eating/body dissatisfied group, and 40% of the US students in that group reported intentional vomiting for weight control. Some of the Asian international students practiced undesirable dieting behaviors and reported body dissatisfaction levels similar to those of many US college women. College health professionals should recognize that disordered eating among Asian women must not be overlooked because of stereotypical perceptions about Asian women's body size and type.

Mitochondrial, but not peroxisomal, beta-oxidation of fatty acids is conserved in coenzyme A-deficient rat liver

Hepatic coenzyme A (CoA) plays an important role in cellular lipid metabolism. Because mitochondria and peroxisomes represent the two major subcellular sites of lipid metabolism, the present study was designed to investigate the specific impact of hepatic CoA deficiency on peroxisomal as well as mitochondrial beta-oxidation of fatty acids. CoA deficiency (47% decrease in free CoA and 23% decrease in total CoA) was produced by maintaining weanling male Sprague-Dawley rats on a semipurified diet deficient in pantothenic acid (the precursor of CoA) for 5 weeks. Hepatic mitochondrial fatty acid oxidation of short-chain and long-chain fatty acids were not significantly different between control and CoA-deficient rats. Conversely, peroxisomal beta-oxidation was significantly diminished (38% inhibition) in livers of CoA-deficient rats compared to control animals. Peroxisomal beta-oxidation was restored to normal levels when hepatic CoA was replenished. It is postulated that since the role of hepatic mitochondrial beta-oxidation is energy production while peroxisomal beta-oxidation acts mainly as a detoxification system, the mitochondrial pathway of beta-oxidation is spared at the expense of the peroxisomal pathway when liver CoA plummets. The present study may offer an animal model to investigate mechanisms involved in peroxisomal diseases.

Effects of B vitamin injections on plasma B vitamin concentrations of feed-restricted beef calves infected with bovine herpesvirus-1

For nonruminants, stress and disease greatly increase requirements for vitamin B6, folic acid, pantothenic acid, and ascorbate. The effects of feed restriction, virus infection, and vitamin injections on plasma concentrations of B vitamins critical to the immune response were evaluated. Twelve beef steer calves, 6 to 8 mo of age, were fed below maintenance for 17 d and deprived of food for 3 d during a 20-d period after weaning. They then were inoculated intranasally with live attenuated bovine herpesvirus-1 (BHV-1). Six calves received saline injections and six received injections of a B vitamin mixture and ascorbate every 48 h for 14 d before and 14 d after inoculation. A mild respiratory infection developed in all calves 4 to 5 d after inoculation. In control calves, restricted intake and food deprivation decreased plasma vitamin B6 and pantothenate and increased vitamin B12 but did not affect folic acid and ascorbate concentrations. Vitamin injections increased plasma concentrations of vitamin B6, folic acid, vitamin B12, pantothenic acid, and ascorbate (P < .002). Plasma concentrations of vitamin B6, vitamin B12, pantothenic acid, and ascorbate, but not folic acid, were markedly reduced in all calves during the BHV-1 infection (P = .001). The vitamin B6, pantothenic acid, vitamin B12, and ascorbate status of stressed calves may affect their immune response to vaccination or infection.

Quantitative use of the Food Guide Pyramid to evaluate dietary intake of college students

OBJECTIVES

To evaluate the usefulness of the Food Guide Pyramid as a quantitative tool for assessing nutritional adequacy and quality.

DESIGN

One-day food records (n = 2,489) were assigned food group scores (1 through 5) by two systems. System 1 recorded the number of food groups on a given record that included the minimum number of servings suggested by the Food Guide Pyramid. System 2 recorded the number of food groups in the Food Guide Pyramid for which at least one serving was included. The food records were further evaluated by mean adequacy ratio (MAR) for iron, calcium, magnesium, vitamin A, and vitamin B-6 (MAR-5 score) and percentage of energy contributed by fat and sugar. Sensitivity and specificity of the food group scores to predict nutritional inadequacy were determined.

SUBJECTS

College students (n = 2,489) attending introductory nutrition, foods, and health-related courses at a mid-western university.

STATISTICAL ANALYSES

Student's t test, chi2 test, Dunnett's multiple mean comparison test.

RESULTS

A food group score of 5 was given to 11% and 35% of the diet records by systems 1 and 2, respectively; MAR-5 scores of 75 or greater were given to 70% of the records. Only 4% of the diets contained both 30% or less and 10% or less of energy from fat and sugar, respectively. Both scoring systems can be used as a quantitative tool for screening nutritional inadequacy with high sensitivity (correctly classifying nutritionally inadequate diets) but with a moderate to low specificity (correctly classifying nutritionally adequate diets).

Relationship of diet, abdominal obesity, and physical activity to plasma lipoprotein levels in Asian Indian physicians residing in the United States

OBJECTIVE

To examine the relationship of total fat, saturated fat, carbohydrate and energy intake, leisure-time activity, waist-to-hip ratio (WHR), and body mass index to the prevalence of atherogenic plasma triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C) levels in Asian Indians living in the United States. High plasma TG and low HDL-C levels have been documented in Asian Indians worldwide.

DESIGN

This exploratory study examined medical history, demographics, anthropometrics, plasma lipids levels, food intake frequency, and self-reported leisure-time activity.

SUBJECTS

153 Asian Indian male physicians (mean age=47 years) were recruited at two annual national conferences of the American Association of Physicians from India, with free medical assessments as incentives.

STATISTICAL ANALYSES PERFORMED

Correlational and multiple regression analyses were performed.

RESULTS

Subjects' diets averaged 56% energy from carbohydrate, 32% from total fat, and 8% from saturated fat. High total fat intake was associated with high WHR (r=.21, P<.01) and high total carbohydrate intake (grams per day) was associated with high TG level (r=.24, P<.05). Leisure-time activity averaged 136 minutes/week and negatively correlated with total plasma cholesterol level (r=.22, P<.01) and low-density lipoprotein cholesterol level (r=.25, P<.001).

APPLICATIONS

Dietitians should recommend moderate dietary carbohydrate intake and meal patterns with energy distributed throughout the day, in addition to decreasing fat consumption, to Asian Indian clients at risk for coronary artery disease. High carbohydrate intake and uneven diurnal distribution (no breakfast and large evening meals) are associated with high TG and low HDL-C levels in this population.

Pantothenic acid uptake and metabolism by red blood cells of rats

Red blood cells (RBC) of rats and humans contain pantothenic acid (PA) derivatives, generally referred to as bound PA, which were never characterized or quantitated. This study was undertaken to define those factors that determine the rates of uptake and efflux of PA, and possibly PA derivatives, in RBC. Uptake of PA by RBC was studied by incubating RBC with different concentrations of PA (0.34-34.0 mumol/L), each containing [14C]PA (0.34 mumol/L) at 37 degrees C for 3-360 min. The effects of Na+, energy and pH on the uptake of PA in RBC were determined in experiments varying media concentrations of Na+ (0-152 mmol/L), glucose (0 and 10 mmol/L) or pH (7.2-7.6). The release of PA from RBC was studied by incubating RBC containing [14C]PA (0.10-10.4 nmol/10(7) RBC, final concentration) in fresh media at 37 degrees C for 10-240 min. Uptake and efflux of PA were found to be nonsaturable; uptake was not affected by Na+, energy or pH. Quantitative and qualitative determination of PA derivatives was by enzymatic hydrolysis of lysed RBC, followed by analysis of PA by RIA and paper chromatography. The RBC were found to contain PA, 4'-phosphopantothenic acid and pantetheine. We conclude that PA diffuses passively into and out of RBC and that RBC contain only PA, 4'-phosphopantothenic acid, pantetheine and no CoA.

Myocardial metabolism of pantothenic acid in chronically diabetic rats

Transport and metabolism of [3H]pantothenic acid ([3H]Pa) was investigated in hearts from control and streptozotocin-induced diabetic rats. In isolated perfused hearts from control animals, the transport of [3H]Pa was linear over 3 h of perfusion when 11 mM glucose was the only exogenous substrate. The in vitro transport of [3H]Pa by hearts from 48-h diabetic rats was reduced by 65% compared to controls and was linear over 2 h of perfusion with no further accumulation of Pa during the third hour. The defect in transport observed in vitro could be corrected by in vivo treatment with 4 U Lente insulin/day for 2 days. In vitro addition of insulin in the presence of 11 mM glucose or 11 mM glucose plus 1.2 mM palmitate had no effect on [3H]Pa transport in hearts from 48-h diabetic rats during 3 h of perfusion. Accumulation of [3H]Pa was not inhibited by inclusion of 0.7 mM amino acids, 1 mM carnitine, 50 microM mersalic acid or 1 mM panthenol, pantoyllactone or pantoyltaurine. Uptake was inhibited by 1 mM nonanoic, octanoic or heptanoic acid, 0.1 mM biotin or 0.25 mM probenecid, suggesting a requirement for the terminal carboxyl group for transport. Transport of pantothenic acid was reduced in hearts from diabetic rats within 24 h of injection of streptozotocin. In vitro accumulation of [3H]Pa decreased to 10% of control 1 week after streptozotocin injection and then remained at 30% of the control value over 10 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Enzymes for liberation of pantothenic acid in blood: use of plasma pantetheinase

Reported normal concentrations for human whole-blood total pantothenic acid vary from 1.1 to 12 mumol/L. This wide range may partly arise from the various enzymes used for liberation of pantothenic acid from coenzyme A, particularly the source of pantetheinase. A purified pantetheinase from pig kidney had greater than 100 times the specific activity and less than 0.01 times the pantothenate content of other commonly used extracts. Endogenous pantetheinase activity in human plasma was identified (11.2 +/- 2.0 mumol pantothenate .min-1.L-1, n = 29) and found comparable to the activity usually added from exogenous sources for liberation of pantothenate from whole blood (1-13 mumol.min-1.L-1). Alkaline phosphatase alone liberated as much pantothenate from hemolyzed whole blood as did alkaline phosphatase with pantetheinase. Previous reports of total blood pantothenate may be elevated by pantothenate in the pantetheinase extracts, an unnecessary source of error. Whole-blood total pantothenate concentrations less than 4.6 mumol/L are normal and do not indicate deficiency, as is often currently quoted.

Effect of pantothenic acid status on the content of the vitamin in human milk

Seventeen lactating women who delivered preterm infants (between 28 to 34 wk of gestational age) and 26 nursing mothers of term infants participated in the study. Each term mother kept a record of 2-day dietary intakes, collected urines for 2 days, and provided fore and hind milk samples and a fasting blood sample at 2 and 12 wk postpartum. Each of preterm women provided fore and hind milk samples once a week for 16 wk starting 2 wk postpartum. The method of determining pantothenic acid content in milk samples was validated, and the vitamin was quantitated by the radioimmunoassay. The average pantothenate levels in fore and hind samples of preterm milk (3.31 and 3.72 micrograms/ml, respectively) were significantly (p less than 0.05) higher than those of term milk (2.64 and 2.48 micrograms/ml, respectively). No significant change was observed in pantothenic acid content within a feeding or with the progress of nursing in both groups. The vitamin content of human milk was compared with the minimum requirement of the Infant Formula Act of 1980. The pantothenate level in term milk was significantly (p less than 0.05) correlated with the vitamin level in maternal circulation and with that of the dietary intake and urinary excretion.