Inclusion of pork meat in the diets of young women reduces their intakes of energy-dense, nutrient-poor foods: results from a randomized controlled trial.

Adherence of young women to dietary recommendations has been examined predominantly by surveys. This study aimed to determine the quality of women's diets relative to the Australian Guide to Healthy Eating (AGHE); and to evaluate dietary changes during an intervention trial with pork meat or an iron supplement. A 12-week randomized trial was conducted in young women who were assigned to one of three groups. They maintained three, seven-day food diaries while continuing their routine diet (CG); taking an iron supplement (SG); or incorporating into their diets 500 g/week of pork (PG). Participants (n = 58) provided dietary information on 1218 diary-days. The serves consumed from the vegetable, fruit and dairy groups were lower (p < 0.001), and from the meat and alternatives group greater (p < 0.001) than the recommended serves. PG consumed significantly fewer (p < 0.001) serves of "extra" foods, and ate fruit more frequently (p < 0.001) than CG and SG. The participants' dietary self-assessment showed poor agreement with the AGHE description of "serve". The inclusion of pork in the diets of young women is associated with the reduced consumption of energy-dense nutrient-poor "extra" foods and increased frequency of fruit intake. The effect may be explained by diverse factors such as increased food knowledge, cooking skills and the effect of pork on satiety.

Biological variability and impact of oral contraceptives on vitamins B(6), B(12) and folate status in women of reproductive age.

Vitamins B(6), B(12) and folate play crucial metabolic roles especially during the reproductive years for women. There is limited reporting of within-subject variability of these vitamins. This study aimed to determine the within and between subject variability in serum vitamins B(6), B(12), folate and erythrocyte folate concentrations in young women; identify factors that contribute to variability; and determine dietary intakes and sources of these vitamins. Data were obtained from the control group of a trial aimed at investigating the effect of iron on the nutritional status of young women (age 25.2 ± 4.2 year; BMI 21.9 ± 2.2 kg/m2). The coefficients of variability within-subject (CVI) and between-subject (CVG) for serum vitamins B(6), B(12)and folate, and erythrocyte folate were calculated. Food frequency questionnaires provided dietary data. CVI and CVG were in the range 16.1%-25.7% and 31.7%-62.2%, respectively. Oral contraceptive pill (OCP) use was associated (P = 0.042) with lower serum vitamin B12 concentrations. Initial values were 172 ± 16 pmol/L and 318 ± 51 pmol/L for OCP and non-OCP users, respectively; with differences maintained at four time points over 12 weeks. BMI, age, physical activity, alcohol intake and haematological variables did not affect serum or erythrocyte vitamin concentrations. Vitamin B12 intakes were derived from traditional and unexpected sources including commercial energy drinks. Young women using OCP had significantly lower serum vitamin B12 concentrations. This should be considered in clinical decision making and requires further investigation.

Iron supplementation decreases plasma zinc but has no effect on plasma fatty acids in non-anemic women.

Limited information is available on the role of iron in fatty acid metabolism in humans. We hypothesized that iron supplementation will increase desaturase activity, and so, the aim of this study was to determine the effect of iron supplementation on fatty acid desaturase activity in young women. Participants were randomly assigned to a control group (CG) or supplementation group (SG) who were provided with 37.4 mg of elemental iron daily for 12 weeks. Forty women completed the trial, n = 19 in CG and n = 21 in SG. The mean ages were 25.2 and 24.6 years, and body mass indices were 21.8 and 21.2 (kg/m(2)) in CG and SG, respectively. Serum ferritin concentrations increased significantly (P < .01) in subjects assigned to SG but were unchanged in CG. Serum iron concentrations were not significantly changed. Plasma zinc concentrations at the end of the intervention were similar to baseline values for individuals in CG but were decreased significantly (P = .004) in SG. Plasma fatty acids, phospholipid fatty acids, and desaturase activities, expressed as precursor-to-product ratios, were not significantly affected by the intervention, although in SG the concentration of serum ferritin was correlated positively (P < .05) with Δ6-desaturase activity. Supplementing non-anemic women with low dose iron improves iron status but has no significant effect on desaturase activity. The lack of a clear effect on an indirect indicator of desaturase activity may be related to the antagonism between iron and zinc, as illustrated by the decrease in plasma zinc concentrations in women who were supplemented with iron.

A randomized controlled trial in young women of the effects of consuming pork meat or iron supplements on nutritional status and feeling of well-being.

OBJECTIVES: Limited information is available on the role of pork meat in influencing iron status. The aim of this study was to determine the effect of consuming pork meat as compared to iron supplementation on nutritional status and feeling of well-being. METHODS: Young women were randomly assigned to a control diet (CG), a pork-containing diet (PG), or a control diet with iron supplementation (SG) for 12 weeks. Sixty-five women aged 24.6 ± 4.4 years (mean ± SD) completed the trial. RESULTS: Serum ferritin concentrations were increased significantly (p = 0.001) in participants assigned to the SG as compared with the other groups, as assessed by repeated-measures analysis of variance. At week 12, hemoglobin concentrations were significantly higher in PG and SG as compared with CG. Plasma zinc concentrations at the end of the intervention were similar to baseline concentrations for individuals in the CG and PG but were decreased significantly (p < 0.05) in SG. Plasma-, erythrocyte-folate, and serum vitamin B6 and B12 concentrations were not significantly affected by the intervention, although the concentrations of vitamins B6 and B12 tended to increase in PG. Well-being, as measured using the Health Survey Short Form (SF-36) and its 8 multi-item scales, showed significant improvement in vitality in SG (p < 0.05) and bodily pain in PG (p < 0.05). No significant relationships were observed between these health concept scores and biomarkers of nutritional status. CONCLUSIONS: Consumption of pork meat by young women maintains hemoglobin levels to the same extent as low-dose iron supplementation and enhances the components of well-being, mainly their perception of bodily pain.