Jeannemarie M. Beiseigel

Whole-Grain Ready-to-Eat Oat Cereal, as Part of a Dietary Program for Weight Loss, Reduces Low-Density Lipoprotein Cholesterol in Adults with Overweight and Obesity More than a Dietary Program Including Low-Fiber Control Foods

OBJECTIVE Weight loss and consumption of viscous fibers both lower low-density lipoprotein (LDL) cholesterol levels. We evaluated whether or not a whole-grain, ready-to-eat (RTE) oat cereal containing viscous fiber, as part of a dietary program for weight loss, lowers LDL cholesterol levels and improves other cardiovascular disease risk markers more than a dietary program alone. DESIGN Randomized, parallel-arm, controlled trial. SUBJECTS/SETTING Free-living, overweight and obese adults (N=204, body mass index 25 to 45) with baseline LDL cholesterol levels 130 to 200 mg/dL (3.4 to 5.2 mmol/L) were randomized; 144 were included in the main analysis of participants who completed the trial without significant protocol violations. INTERVENTION Two portions per day of whole-grain RTE oat cereal (3 g/day oat b-glucan) or energy-matched low-fiber foods (control), as part of a reduced energy ( approximately 500 kcal/day deficit) dietary program that encouraged limiting consumption of foods high in energy and fat, portion control, and regular physical activity. MAIN OUTCOME MEASURES Fasting lipoprotein levels, waist circumference, triceps skinfold thickness, and body weight were measured at baseline and weeks 4, 8, 10, and 12. RESULTS LDL cholesterol level was reduced significantly more with whole-grain RTE oat cereal vs control (-8.7+/-1.0 vs -4.3+/-1.1%, P=0.005). Total cholesterol (-5.4+/-0.8 vs -2.9+/-0.9%, P=0.038) and non-high-density lipoprotein-cholesterol (-6.3+/-1.0 vs -3.3+/-1.1%, P=0.046) were also lowered significantly more with whole-grain RTE oat cereal, whereas high-density lipoprotein and triglyceride responses did not differ between groups. Weight loss was not different between groups (-2.2+/-0.3 vs -1.7+/-0.3 kg, P=0.325), but waist circumference decreased more (-3.3+/-0.4 vs -1.9+/-0.4 cm, P=0.012) with whole-grain RTE oat cereal. Larger reductions in LDL, total, and non-high-density lipoprotein cholesterol levels and waist circumference were evident as early as week 4 in the whole-grain RTE oat cereal group. CONCLUSIONS Consumption of a whole-grain RTE oat cereal as part of a dietary program for weight loss had favorable effects on fasting lipid levels and waist circumference.

Cognitive eating restraint scores are associated with body fatness but not with other measures of dieting in women

Nearly 50% of women report dieting to lose weight, but the ability of cognitive eating restraint (CER) scores to separate women based on indicators of restricted intake has not been adequately demonstrated. We examined the ability of the CER subscale of the eating inventory to distinguish differences in resting energy expenditure (REE), body composition, cortisol, dietary intake, and physical activity, in a group of women. Subjects (20.4+/-2.3 years) were divided into high (score>9; n=31) and low (score< or =9; n=34) CER groups based on questionnaire responses. Indirect calorimetry was used to measure REE and dual-energy X-ray absorptiometry to measure body composition. Salivary and 24-hour urinary cortisol were measured by bioassays. Food frequency questionnaires and 4-day food records, physical activity recalls, and anthropometric measures were completed. Women in the high CER group possessed more fat mass (p<0.05) and higher body fat percent (p<0.05) and consumed more servings of fruits and vegetables per day (p<0.05) compared to women in the low CER group. Differences in other indicators were not observed between CER groups. Our findings suggest that cognitive restraint and body fatness may not be independent of one another.

Dietary calcium does not exacerbate phytate inhibition of zinc absorption by women from conventional diets

BACKGROUND Although calcium inhibits zinc bioavailability in rats, especially from high-phytate diets, the effect of calcium on zinc absorption by humans from practical diets remains unclear. OBJECTIVE The objective was to test the inhibitory effect of dietary calcium, in Western diets with high and low phytate content, on zinc absorption. DESIGN Using a 2 x 2 factorial design, zinc absorption was determined in 10 healthy women from 1-d diets with moderate and high calcium contents of approximately 700 and 1800 mg/d and low and high phytate contents of approximately 440 and 1800 mg/d. Absorption was measured by using extrinsically added (65)Zn and subsequent whole-body scintillation counting. RESULTS Mean (+/-SE) fractional zinc absorption was 32.8 +/- 2.3% from the moderate-calcium, low-phytate diet; 26.9 +/- 2.4% from the moderate-calcium, high-phytate diet; 39.4 +/- 2.4% from the high-calcium, low-phytate diet; and 26.2 +/- 2.3% from the high-calcium, high-phytate diet. The respective values for absolute zinc absorption were 3.8 +/- 0.3, 3.0 +/- 0.3, 4.5 +/- 0.3, and 3.2 +/- 0.3 mg/d. Phytate significantly reduced fractional zinc absorption by approximately 10 percentage points and reduced absolute zinc absorption by 25%, or approximately 1 mg/d. Differences in dietary calcium did not affect zinc absorption, regardless of a high or low dietary phytate content. CONCLUSIONS In healthy women consuming 1-d menus of ordinary foods (some fortified with calcium), dietary phytate reduces zinc absorption, but calcium does not impair zinc absorption, regardless of whether dietary phytate is low or high.

Distal Tibia Areal Bone Mineral Density Use in Detecting Low aBMD of the Hip in Young Women

Dual-energy X-ray absorptiometry (DXA) is a primary clinical tool for identification of adults with low areal bone mineral density (aBMD) and who are at increased risk for future osteoporosis and fragility fractures. Procedures for several aBMD scans of clinical interest might be limited by artifact, inaccessible anatomical regions, and positioning errors. Sites for scanning that overcome these limitations need further investigation for application to large-scale screening and relevance to clinical decisions regarding diagnosis and treatment. In this study, 146 women (mean +/- SE age = 20.1 +/- 0.1 yr, height = 163.3 +/- 0.2 cm, weight = 60.0 +/- 0.2 kg) underwent DXA of the total body (TB) and right and left total proximal femurs (TPF), total forearms (TF), and distal tibiae (DT). Osteopenia was identified in 24 women. Areal BMD was positively related among all measurement sites (r = 0.55-0.81, all p < 0.001). Total body, TF, and DT aBMD each displayed low sensitivity (0.29-0.33) and high specificity (0.95-0.98) to detect osteopenia of the TPF. Addition of TB fat-free mass slightly enhanced the predictive value of DT aBMD. Overall, DT aBMD can discriminate between osteopenic and normal subjects with comparable accuracy to TB or TF aBMD.

Zinc Absorption Adapts to Zinc Supplementation in Postmenopausal Women

Objective: To determine if human Zn absorption adapts to chronic high Zn intakes. Methods: Zn absorption was measured at 0, 8, and 16 wk in healthy postmenopausal women who consumed controlled diets with ∼5 mg Zn from food, supplemented to 14 (n = 6), 32 (n = 3), or 47 (n = 3) mg Zn/d for 22 wk. Zn absorption for 1 day was determined by 65Zn-labeling of meals and whole body scintillation counting. Results: At wk 0, less Zn was absorbed from diets with 14, compared with 32 or 47 mg/d (4.6, 8.7, and 10.3 mg/d, respectively; pooled SE = 0.9; p < 0.05). These differences were not apparent at wk 8 (5.4, 5.8, 6.4; NS) and became negligible by wk 16 (5.0, 5.0, 5.1; NS). Plasma Zn concentrations were unaffected. The results are consistent with a saturation response model of Zn absorption. Conclusion: Within several weeks, postmenopausal women biologically adapted to absorb a relatively uniform amount of 5 mg Zn/d when controlled, Zn-supplemented diets supplied consistent Zn intakes between 14 and 47 mg/d.

Anthropometrics, Bone Mineral Density, and Dietary Intake in a Group of Young Adult Females

Associations between anthropometric, body composition, and dietary intake and measures of bone mineral density (BMD) in young-adult females were explored. Positive associations were found between body weight and TB (p < .05), lumbar spine (LS) (L2-L4, p < .01), and total proximal femur (TPF) BMD (p < .0001); body mass index and LS (p < .05), TPF (p < .0001), and total forearm BMD (p < .01); FFST mass and TB (p < .001), LS (p < .01), and TPF BMD (p <.0001), and fat mass and LS (p < .05) and TPF BMD (p < .01). LS BMD had negative associations with protein, magnesium, and iron intake (all p < .05). Average vitamin D intake had a positive association with ultradistal forearm BMD (p < .01). Findings support the positive influence of body weight and soft-tissue mass on BMD in young adult females.