Development and cross-validation of a prediction equation for estimating resting energy expenditure in healthy African-American and European-American women.

OBJECTIVE: To develop, validate, and cross-validate a formula for predicting resting energy expenditure (REE) in African-American and European-American women. DESIGN: A cross-sectional study of REE in women. Participants were randomly assigned to one of two groups. One group served to develop and validate a new equation for predicting REE while the second was used to cross-validate the prediction equation. The accuracy of the equation was compared to several existing formulae. SETTING: University metabolic laboratory, Memphis, TN, USA. SUBJECTS: Healthy, premenopausal African-American and European-American women between 18 and 39 y of age. The validation sample included 239 women (age: 28.4 y, wt: 70.7 kg, body mass index (BMI): 25.2 kg/m(2), REE: 5840 kJ/day), while the cross-validation sample consisted of 232 women (age: 27.5 y, wt: 70.7 kg, BMI: 25.2 kg/m(2), REE: 5784 kJ/day). RESULTS: The prediction equation derived from the current sample, which included adjustments for ethnicity, was the only formula that demonstrated a high level of accuracy for predicting REE in both African-American and European-American women. The mean difference between REE predicted from the new formula and measured REE was 28 kJ/day (s.d.=668) for European-American women and 142 kJ/day (s.d.=584) for African-American women. CONCLUSIONS: Previous equations for predicting energy needs may not be appropriate for both African-American and European-American women due to ethnic differences in REE. A new equation that makes adjustments in predicted REE based on ethnicity is recommended for determining energy needs in these groups (Predicted REE (kJ/day)=616.93-14.9 (AGE (y))+35.12 (WT (kg))+19.83 (HT (cm))-271.88 (ETHNICITY: 1=African American; 0=European American)). SPONSORSHIP: Support for this study was provided by Grant #HL53261 from the National Heart, Lung, and Blood Institute.

Cigarette smoking is associated with energy balance in premenopausal African-American adult women differently than in similarly aged white women.

OBJECTIVE: To investigate the differential association of cigarette smoking with energy balance in African-American and white premenopausal women. DESIGN: Cross-sectional study of energy balance, weight, and smoking in women. SUBJECT: A total of 374 women: 191 African-American (mean age=29.8+/-6.5 y) and 183 white women (mean age=28.9+/-7.1 y). MEASUREMENTS: Weight, cigarette smoking habits, resting energy expenditure, dietary intake, and physical activity. RESULTS: There were no significant differences in dietary intake by race or smoking status. The model for physical activity was significant (P=0.0004), with body mass index (BMI) having the largest effect on activity (P<0.001). Smoking status was related to activity, with the heaviest smokers reporting more activity than nonsmokers (P=0.008) or light smokers (P=0.028). The model for resting energy expenditure (REE) was significant (P<0.0001), with the largest again being BMI (P<0.001). There was also an interaction between ethnicity and smoking status (P<0.0001) such that African-American nonsmokers and light smokers tended to have lower REE than several other groups, most often the African-American moderate heavy smokers. The model for BMI was significant (P<0.0001) with an interaction for ethnicity and smoking status (P=0.0009). African-American nonsmokers and light smokers had significantly higher BMIs than most of the other groups. CONCLUSION: African-American women who were the heaviest smokers had a lower adjusted BMI than the heaviest smoking white women. This effect, at least partially, may be related to an increased REE in the African-American smoking women. While energy intake did not appear to be important in this relationship, energy expended in physical activity appeared to be increased with smoking, as was REE.

Food sources of calcium in a sample of African-American an Euro-American collegiate athletes.

Adequate calcium intake is integral to bone health as well as for optimal athletic performance. This study was conducted to investigate: (a) food sources of calcium in a sample of collegiate athletes, (b) gender and/or ethnic differences in food sources of calcium, and (c) whether athletes that derive less of their calcium intake from dairy sources increase their calcium intake from supplements or other food sources. Participants were African-American and Euro-American NCAA Division 1-A athletes. Eighty-five men and 59 women participated. Calcium intake for the previous 7-day period was assessed with a brief calcium screen. Men consumed significantly more calcium than women (1,354 vs. 898 mg/day), with female cross-country runners exhibiting the lowest average intake (605 mg/day). Both men and women obtained the majority of their calcium from dairy products and mixed dishes, while men consumed significantly more calcium-fortified foods. Several gender and ethnic interactions for calcium intake from food groups were found. Mean total dairy calcium intake was found to vary according to total calcium intake in men, and supplemental calcium was not used to augment low dairy intakes of calcium in any group. While African-Americans and Euro-Americans athletes were consuming similar levels of calcium, the female athletes in the sample did not get adequate amounts.

Research and the clinical dietitian: perceptions of the research process and preferred routes to obtaining research skills.

The art and science of dietetics are rooted in research, yet clinical dietitians do not generally participate in the research process. Focus group methodology was used to identify clinical dietitians' perceptions about incorporating research into clinical practice and to identify potential barriers to participation in research. In a series of 9 focus group sessions with 50 registered dietitians and 3 dietetic interns, attendees recognized the importance that research findings play in their practice. Barriers such as lack of time and low comfort levels with initiating and conducting research were discussed, and possible solutions to these barriers were suggested. Collaboration with academic dietitians or with research mentors was viewed as a useful and realistic pathway to increased participation in the research process. According to participants, increased involvement in research could also be facilitated by a supportive administrative structure within the facility, clinical management that is supportive of the research process, and collaboration among members of the dietetics staff. The findings of this qualitative investigation indicate that the central tenet of successful integration of clinical practice and research is collaboration-within dietetics departments, across the strata of facilities, and in particular, between clinical and research-oriented registered dietitians.

Energy deficits associated with nasogastric feeding in patients with burns.

This study was designed to identify whether significant energy deficits occur when feedings are (1) withheld perioperatively and (2) withheld because of gastric ileus. We studied patients with more than 20% total body surface area burns, who had survived at least one surgery, and who were intubated within 3 days of admission. Energy needs and energy received from enteral feedings were summed across the period during which the patients underwent surgical procedures. The difference between energy needed and energy received was divided into that caused by feedings being withheld perioperatively and that caused by feedings being withheld because of a gastric ileus. Twenty-five patients (9 women and 16 men) were included in the study. The total energy deficit was a mean of 15,969 kcal (31.6% of 50,546 kcal needed); 58% of the energy deficit (9264 kcal of the 15,969 kcal deficit) was caused by feedings being withheld perioperatively and 42% of the energy deficit (6705 kcal of the 15,969 kcal deficit) was caused by feedings being withheld because of gastric ileus. The withholding of feedings perioperatively and because of gastric ileus were both significant contributors to energy deficits. Future studies are necessary to determine whether energy needs being more closely met would result in improved outcomes for these patients.

Socioeconomic status, ethnicity, and environmental tobacco exposure among non-smoking females.

This study examined the relationship between socioeconomic status (SES) and environmental tobacco smoke (ETS) exposure among non-smoking females, determined which SES variable(s) were most strongly associated with ETS exposure, and examined whether the relationship between SES and ETS exposure was the same for Blacks and Whites. Participants were 404 never-smoker females recruited in the community. Independent variables included income, education, occupation, median income within zip code of participants' residence, and ethnicity. Number of days per week exposed to ETS in the past year was the dependent variable. There was a significant correlation between CO levels (parts per million, ppm) and self-reported ETS exposure (r = 0.22, p < 0.001). The mean CO level exposure was 1.81 +/- 1.19 ppm, and the mean number of days per week of ETS exposure was 4.72 +/- 4.71. The most frequent source of ETS exposure was at public places (64.4%). Although Blacks tended to report higher ETS exposure than Whites (p = 0.08), this tendency disappeared when SES indicators were entered in the model. Correlations among SES indicators were either non-significant or very modest suggesting that different SES indicators may not measure the same construct. Education was the only SES variable that was significantly associated with ETS exposure in this population. The relationship between SES and ETS exposure was similar for both Blacks and Whites. These findings suggest that education may be the most important factor to be considered when designing interventions to decrease ETS exposure among young non-smoking females (e.g., public education of the hazards of ETS exposure and awareness of existing tobacco-control laws and regulations).

The effect of eating out on quality of diet in premenopausal women.

OBJECTIVE: To compare the intake of women who report varying levels of frequency of consuming food at commercial facilities outside the home. DESIGN: A 1-week descriptive study of dietary intake in women. Subjects completed daily diet records that included information regarding the source of the food eaten at each meal or snack. The sample was divided on the basis of the number of meals each subject reported obtaining from a commercial establishment outside the home. Of the 129 subjects, 56% (n = 72) reported eating out 5 times or less during the week of recording (Low Eating Out group) and the remainder (n = 57) reported eating out between 6 and 13 times (High Eating Out group) SUBJECTS/SETTING: One hundred twenty-nine premenopausal women were recruited via community advertising for an investigation of health habits. This study was conducted in a midsouthern US city. STATISTICAL ANALYSES PERFORMED: Results were analyzed using independent sample t tests and chi 2 tests. RESULTS: Mean intake was compared for the groups. The High Eating Out group was found to be consuming significantly more total energy (2,057 kcal vs 1,769 kcal; P = .002), fat (79.5 g vs 60.6 g; P < .001), and sodium (3,299 mg vs 2,903 mg; P = .043) and marginally more carbohydrate (261.5 g vs 234.6 g; P = .055) and protein (71.5 g vs 65.4 g; P = .066). Total fiber or calcium intake did not differ between the groups. CONCLUSIONS: Our study demonstrates that women who report eating out a greater number of times per week report more total energy intake as well as higher fat and sodium intakes. However, the High Eating Out group did not consume significantly more fiber or calcium in the extra energy consumed.