***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objectives : To investigate whether a modest number of food frequency questions are sufficient to describe sociodemographic differences in dietary habits , and to identify sociodemographic characteristics of subjects adhering to food-based dietary guidelines operationalised in a ‘ healthy-diet index ’ . Design : Cross-sectional population survey . Subjects : A total of 480 men , 515 women , aged 15–90 y. R and om sample of private telephone numbers drawn from regional telephone records , geographically stratified . Participation rate 62 % . Methods : Computer-assisted telephone interviews , including six food frequency questions , a question on type of fat spreads used on bread , questions on seven sociodemographic variables . Results : The summary of the healthy-diet index showed that the subjects who adhered to food-based dietary guidelines ( top quintile ) compared to those who did not ( bottom quintile ) were most often women ( odds ratio (OR)=6.07 ; confidence interval ( CI ) : 3.91–9.43 , women vs men ) , of older age ( OR=9.72 ; CI : 3.02–31.31 , old age vs young ) , highly educated ( OR=3.69 ; CI : 1.53–8.92 , high education vs low ) and living in multiperson households including children ( OR=4.66 ; CI : 2.47–8.80 , multiperson household vs single household ) . The results also showed that gender difference in dietary habits is associated with other sociodemographic variables . Conclusions : The selected food frequency questions proved sufficient to describe sociodemographic differences in dietary habits , and this method may be a valuable supplement to traditional quantitative dietary surveys in monitoring sociodemographic changes in eating patterns . The results also underline the influence of sociodemographic status on dietary habits . Sponsorship : The Danish Nutrition Council funded the study Background Vegetarian diets have been associated with lower risk of chronic disease , but little is known about the health effects of low meat diets and the reliability of self-reported vegetarian status . We aim ed to establish an analytical cohort over-represented with vegetarians , pescetarians and 1 day/week meat consumers , and to describe their lifestyle and dietary characteristics . In addition , we were able to compare self-reported vegetarians with vegetarians whose status has been confirmed by their response on the extensive food frequency question naire ( FFQ ) . Study methods Embedded within the Netherl and s Cohort Study ( n = 120,852 ; including 1150 self-reported vegetarians ) , the NLCS-Meat Investigation Cohort ( NLCS-MIC ) was defined by combining all FFQ-confirmed-vegetarians ( n = 702 ) , pescetarians ( n = 394 ) , and 1 day/week meat consumers ( n = 1,396 ) from the total cohort with a r and om sample of 2–5 days/week- and 6–7 days/week meat consumers ( n = 2,965 and 5,648 , respectively ) . Results Vegetarians , pescetarians , and 1 day/week meat consumers had more favorable dietary intakes ( e.g. higher fiber/vegetables ) and lifestyle characteristics ( e.g. lower smoking rates ) compared to regular meat consumers in both sexes . Vegetarians adhered to their diet longer than pescetarians and 1 day/week meat consumers . 75 % of vegetarians with a prevalent cancer at baseline had changed to this diet after diagnosis . 50 % of self-reported vegetarians reported meat or fish consumption on the FFQ . Although the misclassification that occurred in terms of diet and lifestyle when merely relying on self-reporting was relatively small , the impact on associations with disease risk remains to be studied . Conclusion We established an analytical cohort over-represented with persons at the lower end of the meat consumption spectrum which should facilitate prospect i ve studies of major cancers and causes of death using ≥20.3 years of follow-up The effects on  pregnancy outcome  and  maternal iron status of powdered milk ( PUR ) and a milk-based fortified product ( V-N ) were compared in a group of underweight gravidas . These take-home products were distributed during regular prenatal visits . Women in the V-N group had greater weight gain ( 12.29 vs 11.31 kg , p less than 0.05 ) and mean birth weights ( 3178 vs 3105 g , p less than 0.05 ) than those in the PUR group . Values for various indicators of maternal Fe status were also higher in the V-N group . Compared with self-selected noncompliers , similar in all control variables to compliers , children of women who consumed powdered milk or the milk-based fortified product had mean birth weights that were higher by 258 and 335 g , respectively . Data indicate a beneficial effect of the fortified product on both maternal nutritional status and fetal growth The effect of increasing dietary folate on folate status during pregnancy is controversial . The aim of this study was to compare folate intake and folate status during pregnancy of women with high long-term vegetable intake and those eating an average Western diet .  In a prospect i ve study that included 109 participants , pregnant women adhering to a predominant vegetarian diet with high vegetable intake for 8 + /- 0.5 y with subgroups of ovo-lacto vegetarians ( n = 27 ) and low meat eaters ( n = 43 ) and women eating an average Western diet ( control group , n = 39 ) were compared with regard to dietary intake and plasma and red blood cell ( RBC ) folate concentrations during wk 9 - 12 , 20 - 22 and 36 - 38 of gestation . Plasma and RBC folate concentrations were highest in ovo-lacto vegetarians , followed by low meat eaters and lowest in the controls . Ovo-lacto vegetarians and low meat eaters showed a lower risk for folate deficiency , with RBC folate concentrations of < 320 nmol/L result ing in odds ratios of 0.10 ( 95 % confidence interval , 0.01 - 0.56 ) and 0.52 ( 95 % confidence interval , 0.20 - 1.34 ) , respectively . In ovo-lacto vegetarians , the RBC folate concentration was positively related to the intake of vitamin B-12 ( r = 0.51 , P : < 0.0001 ) . The results of the study suggest that long-term high vegetable intake favorably affects plasma folate as well as RBC folate concentrations throughout pregnancy and reduces the risk of folate deficiency if an adequate vitamin B-12 supply is ensured This study is a r and omized controlled double-blind trial on the effects of nutrition supplement of pregnant and lactating women on their offspring . The study was conducted by the late Dr. Bacon Chow in 14 villages in Sui-Lin township , a farming area about 180 miles from Taipei , Taiwan . Two hundred ninety-four women were r and omly assigned to one of two treatment groups . The daily supplement for one group provided 800 kcal and 40 g of protein/day ; for the other group it only provided 80 kcal/day . Supplementation began after 3 wk of the delivery of a first study infant , continued throughout lactation , and through the pregnancy and lactation of a second study infant . Between group comparisons on the birth weight , number of low birth weight infants , or incidence of fetal deaths showed no statistically significant findings . However , the birth weight of the second study infant was statistically different and higher than that of the first study infant in the high supplement group . Moreover , in the low supplement group there was a correlation of 0.22 ( p = 0.06 ) between the change scores for birth weight from the first to the second study infant and the quantity of supplements consumed during the last trimester of pregnancy . There was also in this same group a significant slope in a linear regression of birth weight on total daily caloric intake during the 3rd trimester of pregnancy for the male second study infants . These findings are partly in agreement with findings from three other large supplementation studies in Colombia , Guatemala , and New York . In this study the findings indicate that caloric supplementation does result in a small yet statistically meaningful increment in birth weight within a population which is not nutritionally at risk BACKGROUND Few data exist for the effects of multiple micronutrient ( MM ) or food supplementation to undernourished pregnant women on their offsprings ' development . OBJECTIVE We aim ed to compare the effects on infant development of early ( 8 - 10 wk gestation ) or usual ( approximately 17 wk gestation ) supplementation with food and MM , 30 mg Fe + 400 microg folate , or 60 mg Fe + 400 microg folate . DESIGN A large , r and omized , controlled trial of pregnancy supplementation was conducted in Bangladesh . A sub sample of infants ( n = 2853 ) were assessed on 2 problem-solving tests ( support and cover tests ) , the motor index of the Bayley Scales of Infant Development , and Wolke 's behavior ratings at 7 mo of age . RESULTS There were no significant effects of any intervention in the group as a whole . However , infants of undernourished mothers [ body mass index ( BMI ; in kg/m2 ) < 18.5 ] who received early food supplementation performed slightly but significantly ( P = 0.035 ) better on the support test than did infants of mothers who received usual food supplementation ( z score : 0.17 ; 95 % CI : 0.01 , 0.33 ) . There were no benefits in infants of higher- BMI mothers ( P = 0.024 for BMI x food interaction ) . Children of low- BMI mothers who received MMs had slightly better motor scores ( z score : 0.28 ; 95 % CI : 0.08 , 0.48 ) and activity ratings ( z score : 0.24 ; 95 % CI : 0.037 , 0.45 ) than did those who received 30 mg Fe + 400 microg folate , whereas other children did not benefit ( P = 0.05 for both motor scores and BMI x micronutrients and for activity and BMI x micronutrients ) . CONCLUSIONS Small benefits from early food and MM supplementation were found in infants of low- BMI but not of high- BMI mothers . However , the benefits were of doubtful functional importance , and longer follow-up is required to determine programmatic implication BACKGROUND Iron deficiency during pregnancy is associated with adverse birth outcomes , particularly , if present during early gestation . Iron supplements are widely recommended during pregnancy , but evidence of their benefit in relation to infant outcomes is not established . This study was performed in the UK , where iron supplements are not routinely recommended during pregnancy , to investigate the association between iron intake in pregnancy and size at birth . METHODS From a prospect i ve cohort of 1274 pregnant women aged 18–45 years , dietary intake was reported in a 24-h recall administered by a research midwife at 12-week gestation .  Dietary supplement intake  was ascertained using dietary recall and three question naires in the first , second and third trimesters . RESULTS Of the cohort of pregnant women , 80 % reported  dietary iron intake below the UK Reference Nutrient Intake of 14.8 mg/day . Those reported taking iron-containing supplements in the first , second and third trimesters were 24 , 15 and 8 % , respectively . Women with dietary iron intake > 14.8 mg/day were more likely to be older , have a higher socioeconomic profile and take supplements during the first trimester . Vegetarians were less likely to have low dietary iron intake [ odds ratio = 0.5 , 95 % confidence interval ( CI ) : 0.4 , 0.8 ] and more likely to take supplements during the first and second trimesters .  Total iron intake , but not iron intake from food only , was associated with birthweight centile ( adjusted change = 2.5 centiles/10 mg increase in iron , 95 % CI : 0.4 , 4.6 ) . This association was stronger in the high vitamin C intake group , but effect modification was not significant . CONCLUSION There was a positive relationship between  total iron intake , from food and supplements , in early pregnancy and birthweight . Iron intake , both from diet and supplements , during the first trimester of pregnancy was higher in vegetarians and women with a better socioeconomic profile OBJECTIVES The purpose of this project was to develop a detailed , in-home , prenatal nutrition intervention protocol for low-income women and to assess the effectiveness of the intervention in improving their dietary intake . A secondary objective was to identify predictors of infant birth weight . DESIGN A defined protocol was developed and nutritionists followed it to conduct in-home nutrition sessions that included nutrition assessment , education , counseling , and goal setting for low-income women during their pregnancies . A pre/post design was used to assess the effects of the nutrition program on dietary intake . A control group was used in evaluating the effect of the nutrition intervention on birth weight . SUBJECTS/ SETTING Forty low-income pregnant women selected r and omly by the county health department nursing staff completed the nutrition intervention . Twenty-six women were also selected to serve as a control group . INTERVENTION For women in the intervention group , in-home visits were conducted weekly for 4 weeks , followed by 2 monthly visits . The purpose of the in-home visits was to use the defined 
    Output:
    
The nine heterogeneous studies on microelements and vitamins suggest vegan-vegetarian women may be at risk of vitamin B12 and iron deficiencies .