The nutrient intakes of pregnant and lactating mothers of good socio-economic status in Cambridge, UK: some implications for recommended daily allowances of minor nutrients

Abstract

1. Forty-two mothers from social classes I, I1 and IIInon-manual and twenty-one from social classes IIImanual (M), IV and V were studied longitudinally. The mean daily nutrient intakes in months 4-9 of pregnancy, months 2 4 of lactation and 3 and 6 months post-lactation are presented and are compared with the U K and the US recommended daily allowances (RDA).2. The quality of the diets (nutrients per 4184 kJ (1000 kcal)) was found to be better than that of other adult female populations studied in the UK, except for a group of dietitians.3. The mean daily intakes of nutrients for which there are UK RDA were almost all greater than 100% of the RDA. The exceptions were iron, which in the manual group (social classes IIIM, IV and V) was 85% of the RDA in pregnancy and 75% post-lactation, and vitamin D.4. Among the nutrients for which there are US, but not UK RDA, only phosphorus and vitamin B,, intakes were greater than 100% of the RDA in both groups at all stages of the study. Intakes of other nutrients were below the RDA: pantothenate 7G91, vitamin B,, zinc, vitamin E and copper 4G72, folate 2144, and biotin <20% of the RDA.5. The bases of the RDA for adult women were examined; for most nutrients the information is limited. It was concluded that the RDA for magnesium, vitamin E and pantothenate are probably higher than necessary and that deficiency is unlikely; that zinc, copper, vitamin B, and folate are probably 'marginal' nutrients for 'at risk' groups; and that information on biotin is insufficient even roughly to assess the dietary requirement.Recommended daily allowances (RDA) are normally set at levels believed to cover the needs of the majority of the population.. The Department of Health and Social Security (DHSS) (I 979) defines them as 'the amount of the nutrient which should be provided per head in a group of people if the needs of practically all members of the group are to be met', and in the USA the National Research Council (1980) Food and Nutrition Board defines them as 'the level of intake . . . considered . . . adequate to meet the . . . needs of practically all healthy persons'.There are three main bases for establishing RDA: knowledge of the intakes of apparently normal, healthy populations and of populations known to be deficient; knowledge of the amounts required to cure clinical or biochemical signs of deficiency; and studies of metabolism such as measurement of rates of nutrient turnover, or of levels required to maintain metabolic balance or tissue saturation. Such information is used to establish an average requirement for the population, which is then increased by a factor to allow for variability of requirement within that population, and a further factor to allow for inefficient utilization (poor absorption, inefficient conversion of precursors, etc.).The tendency therefore is to set RDA higher rather than lower, and to set them at levels greater than the needs of many individual members of the population. This tendency may be exaggerated when information on which to base estimates o...

Maternal prenatal dietary potassium, calcium, magnesium, and infant blood pressure.

“…The association of the sociodemographic characteristics with maternal prenatal cation intakes is similar to other studies in pregnant women 23 - 24 and in nonpregnant adults. 25 The increased intake of potassium, calcium, and magnesium in pregnant women with increasing years of education and managerial and professional occupations is possibly due to heightened awareness of nutrition in healthy pregnancies.…”

“…Pregnant women from Cambridge, UK, consumed approximately 1,200 mg daily, with women from manual labor families consuming less than those from non-manual labor families. 24 Recent reports of calcium intake in pregnancy among the Supplemental Food Program for Women, Infants, and Children participants and controls 2627 are also lower than those in the current study. In a study of low-income pregnant women in Boston, daily calcium intake, assessed by a similar food frequency questionnaire to that used in the present study, averaged almost 1,300 mg. 18 This slightly higher intake could be due to self-selected diets reflecting recent publicity about the health benefits of calcium or to strict adherence to obstetricians' calcium intake recommendations, among other factors.…”

Associations between reproduction and maternal body weight: examining the component parts of a full reproductive cycle

“…Studies from the US, UK, New Zealand, Sweden and The Netherlands indicate that well-nourished lactating women consume more energy than NP=NL women (Institute of Medicine, 1991;Black et al, 1986;Goldberg et al, 1991;Todd & Parnell, 1994;Sadurskis et al, 1988;Van Raaij et al, 1991). In these studies, total intakes were below recommended levels, which may reflect underestimation in the dietary assessment and=or conscious efforts by lactating women to lose weight gained during pregnancy.…”

Breast pain in lactating mothers

“…Previous studies have shown that the protein intake of local lactating mothers is much higher than that of those in other countries. At 3 months postpartum, Hong Kong mothers had a protein intake of 98 g/day 5 compared to 81 g/day in the UK 6 and 80 g/day in Japan. 7 In the first month after delivery (known locally as the confinement period), the protein intake was even higher (133 g/day) 5 than at 3 months.…”