Maternal Energy Intake Research Articles

Impact of Food Supplementation during Lactation on Infant Breast-Milk Intake and on the Proportion of Infants Exclusively Breast-Fed

To evaluate whether milk production can be improved by increasing food intake, a randomized, double-blind, supplementation trial was completed among 102 lactating Guatemalan women. The subjects were undernourished, as indicated by their low values for calf circumference (CC) and the small size of their infants at birth. A high-energy (2.14 MJ/d, HES) and a low-energy (0.50 MJ/d, LES) supplement were distributed 6 d/wk from wk 5 to 25 of lactation. Data were evaluated using repeated-measures analysis of variance on the increments from initial values for each outcome variable with one-tailed tests of statistical significance. The maternal energy intake increased 1.18 MJ/d (P < 0.01) more among the HES than the LES women. Benefit from supplementation was more evident among the more undernourished (CC ≤ median value, 29.5 cm) women. Among these 53 lower-CC women, infant milk and milk energy intakes were 10% higher (64 g/d and 14 MJ/d, respectively, at wk 25) in the HES than the LES group. After controlling for other determinants of infant milk and energy intakes in regression analyses, the significance of these differences increased to P < 0.04. However, there was no detectable effect on infant growth. Logistic regression analysis was used to show that HES women were significantly (P < 0.05) more likely than LES women to be exclusively breast-feeding their infants at wk 20, the time when the effect of supplementation was most evident. These findings establish that milk production and the duration of exclusive breast-feeding of undernourished women can be improved with the provision of supplemental food.

Effect of Chronic Maternal Calcium (Ca) Supplementation on Fetal Bone Mineralization (FBM). † 1535

Pregnancy is a time of physiologic stress on Ca homeostasis but there has been no systematic study on the effect of maternal Ca intake on FBM. We tested the hypothesis that maternal Ca supplementation increases FBM as indicated by dual energy X-ray absorptiometry (DXA) measurements of the neonate. Two hundred eighty-nine women enrolled in a randomized trial of Ca supplementation during pregnancy were approached to participate in a study of FBM; 276 agreed. The women had been randomized to receive 2-g elemental Ca or placebo tablets daily from 13-21 wks gestation until delivery. At each prenatal visit compliance was determined by pill counts. The treatment grp received an average of 1284 mg supplemental Ca/d. All mothers were provided with the same prenatal vitamin supplement. There were no significant differences in maternal dietary Ca, protein and energy intake between grps based on the average of 24-hr recalls conducted at randomization and at 32-33 wks gestation. There was also no significant difference between grps in maternal body mass index and wt gain during pregnancy. Eight neonates were not studied because of 2 deaths, 5 technical problems with DXA and learly discharge. Twelve infants had delayed DXA studies beyond one week after birth because of illness. Of the remaining 256 infants (128/grp), DXA measurements were performed by the same operator at 1.75 (mean) ± 0.1 (SEM) d. Scan acquisition used Hologic 1000/W densitometer (Hologic Inc., Waltham, MA) and infant platform. Quality control scans using manufacturer supplied phantom showed a long term (>3 yrs) CV of<0.5%. Only scans without movement artifact were analyzed using software(v5.64 for total body and v4.57Q for spine) developed in conjunction with the manufacturer. General linear modeling showed that the mean total body bone mineral content (BMC) and lumbar spine BMC were significantly (p<0.05) higher in the treatment grp (13.4% and 14.6%, respectively) at the lowest quintile of maternal dietary Ca intake (mean 504 [treatment] vs 555 [placebo] mg/d). The effect of Ca supplementation on FBM was not significantly different at the highest quintile of dietary Ca intake. We conclude that FBM can be significantly improved by Ca supplementation at low maternal dietary Ca intake.

Increased Energy Intake in Pregnant Smokers Does Not Prevent Human Fetal Growth Retardation

A retrospective cohort study of 729 smoking and 610 nonsmoking pregnant women participating in the Prince Edward Island Prenatal Nutritional Counselling Program (1979–1989) was undertaken to study whether lower energy intake results in lower maternal weight gain and/or a higher rate of small-for-gestational-age infants (SGA) among smokers. A second objective was to quantify, using etiological fractions, the independent contributions of cigarette smoking, maternal pregravid underweight and low pregnancy weight gain to the risk of SGA. Measurements of maternal pregravid weight, height, pregnancy weight gain, smoking status, physical activity, energy intake by a series of 3-d food records throughout the duration of pregnancy, and infant birth weight were collected for women with uncomplicated pregnancies resulting in full-term singleton infants. Multiple linear regression analyses were performed to predict the effect of smoking on maternal energy intake, weight gain and infant birth weight. The independent contributions of smoking, pregravid underweight and low pregnancy weight gain to the risk of SGA were determined using logistic regression analysis. Smoking was independently associated with a higher energy intake [+702 kJ/d (+168 kcal/d)] but with lower maternal weight gain (-2.16 kg) and infant birth weight (-205 g). Dietary energy intake was positively associated with only a small increment in birth weight [5.9 g per 418 kJ (100 kcal)]. The etiologic fraction for SGA attributable to smoking was 30.8%, pregravid underweight 16.7%, and low gestational weight gain 15.3%. We conclude that the important negative effect of smoking on retarding fetal growth cannot be adequately mitigated by simply increasing energy intake.

Dietary and serum folate: their influence on the outcome of pregnancy

We examined the influence of folate intake from diet and supplements b y 28 wk of gestation and third trimester circulating concentrations of serum folate on the outcome of pregnancy in women from Camden, NJ. Mean daily folate intake by week 28 included both dietary and supplemental folate obtained prospectively in 832 women. Circulating concentrations of serum folate as well as serum vitamin B-12 were assayed at 28 wk of gestation (+/- 2 wk) by radioimmunoassay. The outcomes of interest included preterm delivery (<37 wk) and infants with low birth weight (<2500 g). Mean folate intake was significantly correlated with circulating concentrations of serum folate (r=0.17, P<0.001). Women with a low mean daily folate intake (</-240 microgram/d) had an approximately twofold greater risk of preterm delivery and infant low birth weight after maternal characteristics, energy intake, and other correlated nutrients were controlled for. Lower concentrations of serum folate at week 28 were also associated with a greater risk of preterm delivery and low birth weight.

Nutrition and reproductive outcome in maternal phenylketonuria.

Maternal weight gain and intake of selected nutrients were correlated with plasma phenylalanine (Phe) concentrations and reproductive outcomes (in 150 and 142 subjects respectively) in the Maternal PKU Collaborative Study. Daily protein intake was negatively correlated with plasma Phe concentration. Birth length, weight and head circumference of offspring were negatively influenced by the length of time required for the maternal plasma Phe to decline below 600 mumol/l (10 mg/dl) and positively influenced by weight gain of mother as a percentage of recommended weight gain. Birth weight and length were positively correlated with maternal protein and energy intakes. During the first trimester, intakes of fat, calcium, phosphorus, vitamin A and folate were significantly greater in women who had a good reproductive outcome than by women who had a poor outcome. In addition to plasma Phe control in maternal phenylketonuria (PKU), maternal weight gain and dietary intake of protein, energy and fat were correlated with outcome. Therefore, nutrient intake and maternal weight gain should be considered along with plasma Phe concentration when managing the therapy of a pregnant woman with PKU.

The traditional humoral food habits of pregnant Vietnamese–Australian women and their effect on birth weight

Vietnamese-Australian women have infants with lower birth weight than Australian-born women. Traditional humoral food habits, based on ancient Chinese medicine, are more likely to be followed during life changes like pregnancy. These food habits may influence maternal energy intake, weight gain and therefore infant birth weight. This study determined the proportion of pregnant Vietnamese women in southwestern Sydney who practise traditional humoral food habits, and their effect on birth weight. A cohort of 113 pregnant Vietnamese-born women were questioned on smoking status, height, weight, parity, food practices and demographics. Dietary intake was measured in each trimester. Known risk factors and infant birth weights were collected from medical records for participants and nonresponders. Fifty-seven per cent practised the traditional food habits. There were no differences in energy intake or weight gain between the two groups. After adjusting for confounders, birth weight was estimated to be 3257 g (95 per cent confidence interval (CI) 3205 to 3309) and 3272 g (CI 3211 to 3333) for the infants of traditional and nontraditional women respectively. Following humoral food habits does not appear to affect birth weight. Women who choose to follow these traditions should not be discouraged from doing so.

Changes In Body Composition During The Postpartum Period

The common belief: that lactating women experience greater weight and fat loss than their non-lactating counterparts during the postpartum period has often been cited by pregnant women as an advantage of breastfeeding. We classified 28 women, aged 21 to 39. years, into 5 groups according to length of lactation. Group 1 consisted of 5 women non-lactating women. Group 2 breastfed solely 1–3 months and consisted of 5 women. Nine women were in group 3 whom breastfed solely 4–6 months. Group 4 consisted of 4 women who breastfed solely 7–9 months, and group 5 consisted of 5 women who: breastfed solely 10–12 months. Body composition measurements were taken at 1, 2, 3, 6, and 12 months postpartum and included body weight; percent body fat; bicep and tricep skinfold thickness; and maternal energy intake and expenditure. A steady but significant decline in mean maternal body weight occurred in all groups over the 12 month postpartum period (p=0.008); however, there were no significant differences between the 5 groups (p=0.703). Likewise, the percent body fat resulted in a significant decrease for all groups (p=0.005), while there was no significant difference between the groups (p=0.513). The bicep and tricep skinfold thickness did not change significantly between the groups during the 12 month postpartum period (p=0.688 and p=0.434 respectively). The calculated energy intake did not change significantly between groups during the 12 month postpartum period (p=0.139). In fact, the mean caloric level of all groups never actually reached the RDA level for non-pregnant, non-lactating females. Furthermore, the estimates of energy expenditure for maintenance and activity did not differ between the groups (p=0.564). These results do not support the cannon belief that breastfeeding facilitates greater weight loss in the postpartum period.

Low sodium diet in pregnancy: effects on maternal nutritional status

In the present study, besides the effect on blood pressure, the effects of a low sodium diet in pregnancy on maternal energy and nutrient intake, calcium metabolism, zinc and magnesium status, weight gain and body fat storage were investigated. No effect of the low sodium diet in pregnancy on the course of blood pressure and the incidence of hypertensive disorders was observed. The reduction in sodium intake also caused a significant reduction in the intake of energy, protein, carbohydrates, fat, calcium, zinc, magnesiuim, iron and cholesterol. The reduced intake of calcium, zinc and magnesium in the women on the low sodium diet did not result in signficant changes in circulating total calcium, ionized calcium, parathyroid hormone, zinc, alkaline phosphatase or magnesium, probably because of homeostatic adaptations by the kidneys. In the women on the low sodium diet non-significant reductions in weight gain (1.5 kg) and fat mass gain (0.9 kg) over pregnancy were observed. These reductions in weight and fat mass gain were more pronounced (3.4 kg ( P=0.003) and 1.3 kg ( P = 0.15), respectively) when only the data of the women with good compliance were analyzed. The use of a low sodium diet in pregnancy did not have significant effects on infant birth weight, placental weight or other pregnancy outcome variables.

Effects of protein and energy intake, body condition, and season on nutrient partitioning and milk production in caribou and reindeer

We used captive caribou (Rangifer tarandus granti) and reindeer (Rangifer tarandus tarandus) to study the effects of energy intake, protein intake, dietary protein:energy ratio, date, and body condition on (i) body fat versus body protein deposition and (ii) maternal tissue deposition versus milk production. Energy intake was the only variable significantly affecting body mass (BM) changes in either breeding or nonbreeding adult females. Lactating and nonlactating females had comparable efficiency coefficients for net energy retention (60 and 65%, respectively), but the daily maintenance requirement for lactating females (457 kJ/BM0.75) was twice that for nonlactating individuals (232 kJ/BM0.75). In both lactating and nonlactating females, the proportion of tissue deposited as fat rather than protein increased between spring and fall but decreased with increasing fatness. Energy intake increased protein deposition in lactating females but increased fat deposition in nonlactating females. Milk water volume increased with maternal energy intake and decreased with calf age. However, production of milk dry matter, milk fat, and milk energy were not affected by maternal energy or protein intake, maternal body condition, or calf age. Production of milk lactose correlated with maternal energy intake, while production of milk protein correlated with the maternal dietary protein:energy ratio.

Case report: failure to thrive in a breast-fed infant is associated with maternal dietary protein and energy restriction.

To determine whether failure to thrive in a breast-fed infant could be attributed to altered milk production or composition from a mother who consumed a self-imposed energy- and protein-restricted diet. We evaluated the changes in growth and body composition, dietary intakes, and milk production and composition in a mother-infant pair throughout the first postpartum year. The Children's Nutrition Research Center Metabolic Research Unit. A breast-feeding mother-infant pair. Body composition was measured by total body electrical conductance, dietary intakes by food records, milk production by the test weighing procedure, and milk composition by proximate analyses. A marked decline in the infant's linear and ponderal growth rates occurred when the mother consumed an energy- (20 kcal.kg-1.d-1) and protein- (0.7 g.kg-1.d-1) restricted diet. The retardation in body weight gain was associated with an arrest of body fat, but not lean body mass, accretion. Maternal milk production showed positive relationships with maternal dietary energy (p < 0.01, r = 0.93) and protein (p < 0.05, r = 0.83) intakes. Milk composition reflected changes consistent with those of weaning rather than a sequela of the mother's diet. We concluded that failure to thrive in a breast-fed infant could be attributed to reduced milk production in conjunction with maternal dietary energy- and protein-restriction and that an assessment of maternal dietary intakes is essential in an evaluation of the breast-fed infant with failure to thrive.

Impact of lactation on women with cystic fibrosis and their infants: A review of five cases

Objective To evaluate the impact of lactation on the health status of women with cystic fibrosis and their infants. Design Data were acquired through a retrospective review of pulmonary, obstetric, and pediatric medical records. Setting A medical school-based Pediatric Cystic Fibrosis Center in Philadelphia, Pa. Subjects Five women with cystic fibrosis and their respective infants. Main outcome measures For the women, measures of pregravid, gravid, and postpartum height, weight, pulmonary function test results, and energy intake were determined. For the infants, birth Apgar scores were obtained, as were measures of growth and development. Statistical analyses performed Means and standard deviations were calculated. Data were compared with published standardized references. Results Mean maternal age at conception was 25.4±4.1 years. Mean pregravid weight was 60.0±10.7 kg of standard body weight for height (range = 50.8 to 76.7 kg; median = 58 kg). Two women consumed up to two enteric-coated supplemental enzyme capsules per meal, three women consumed none. Pulmonary disease was mild in four of the five women. Mean weight gain during pregnancy was 10.2±7.4 kg. Mean gestation was 37.4±1.5 weeks; mean birth weight was 3.0±0.5 kg. Sweat tests performed on all infants were negative. Duration of breast-feeding was 3 to 30 weeks. Four of the five infants maintained appropriate growth velocity during breast-feeding. Mean maternal energy intake during lactation was above the Recommended Dietary Allowance for lactating women. Four of the five women were at or above their standard body weight during lactation. Conclusions/applications We conclude that women with the clinical diagnosis of mild cystic fibrosis disease can maintain a normal pregnancy with appropriate weight gain and can deliver infants of normal weight for gestational age. During lactation, women with mild cystic fibrosis disease can maintain their own weight and support growth in healthy infants. The dietitian needs to be an integral member of the health care team in assessing, monitoring and managing, women with cystic fibrosis during their child-bearing years.

Restriction of Maternal Dietary Carbohydrate Decreases Fetal Brain Indoles and Glycogen in Rats

In spite of evidence that dietary carbohydrate can increase brain tryptophan and 5-hydroxytryptamine in adult rats, the possible influence of maternal dietary carbohydrate on fetal brain indoles has received little attention. We studied the effect of graded levels (0, 4, 12 and 60%) of maternal dietary fructose or glucose fed throughout pregnancy on fetal brain glycogen and indoles. The diets were isoenergetic and met the NRC energy requirements for pregnant rats. The results demonstrated that low maternal dietary carbohydrate, with adequate energy intake, reduced fetal brain weight and concentrations of glycogen, tryptophan, 5-hydroxytryptamine and 5-hydroxyindoleacetic acid. There were no significant differences between glucose and fructose feeding at any dietary carbohydrate level for any fetal brain measurements, showing that it was the level and not the type of dietary carbohydrate that was important. Significant correlations between fetal brain 5-hydroxytryptamine and brain glycogen, and between fetal brain 5-hydroxytryptamine and brain weight, suggested that lowered brain 5-hydroxytryptamine was only one symptom of disrupted brain development in fetuses of dams fed low levels of carbohydrate. The results show that dietary carbohydrate restriction during pregnancy can have adverse effects on fetal brain development, glycogen levels, and neurotransmitter synthesis even when maternal dietary protein and energy intake are adequate.

Prolonged Lactation Contributes to Depletion of Maternal Energy Reserves in Filipino Women

This paper identifies determinants of women’s postpartum weight and weight change in a large group of Filipino women followed for 24 mo. Longitudinal, multivariate models focused on the effects of lactation, while controlling for energy intake, energy expenditure, reproductive history and seasonality. Lactation was found to have a significant negative effect on weight of urban women. The negative effects of lactation increased with the intensity and duration of breast-feeding. Among rural women negative effects of lactation on weight were observed only after 10–14 mo. Models of net postpartum weight change (from 2 to 24 mo) among nonpregnant women confirmed an important role for lactation. The likelihood of weight loss was significantly increased by lactation of more than 12-mo duration, by greater maternal age and by low dietary energy intake. The effects of lactation on maternal energy reserves can be mitigated substantially be increasing maternal dietary energy intakes.

(Patho)physiological implications of chronic dietary sodium restriction during pregnancy; a longitudinal prospective randomized study

To study the possible pathophysiological implications of long continued dietary sodium restriction in pregnancy. Longitudinal prospective randomized study of the effects of a low sodium diet compared with unrestricted sodium intake in pregnancy. Academic Department of Obstetrics and Gynaecology at Sint Radboud Hospital, Nijmegen, The Netherlands. 42 healthy nulliparous women. A low sodium diet (20 mmol sodium daily) started in the 14th week of pregnancy and stopped after delivery. Maternal weight gain, food intake, blood pressure, cardiac output, systemic vascular resistance, haematocrit and birthweight. Total maternal weight gain and dietary energy intake during pregnancy and weight at 1 and 6 weeks postpartum were significantly lower in the low sodium group. Blood pressure during pregnancy did not show major differences. Stroke volume and cardiac output during pregnancy were significantly lower in the low sodium group whereas systemic vascular resistance was significantly higher. Haematocrit values in the low sodium group tended to be lower during pregnancy, but were significantly lower at 1 and 6 weeks postpartum than in the unrestricted group. Placental and birthweights were not significantly different between the two groups. Chronic dietary sodium restriction during pregnancy is characterized by a diminished body fat accumulation and a reduction in circulating volume, due to a decrease in both plasma and red cell volume, in combination with a high systemic vascular resistance without major effects on blood pressure and birthweight.

Influence of moderate nutritional stress during gestation on reproduction of Collared peccaries (Tayassu tajacu)

This study examined the influences of moderate restrictions in maternal energy and protein intake during gestation on reproductive success and foetal development in the Collared peccary (Tayassu tajacu). Sixteen captive females from southern Texas were bred during January 1983 and randomly assigned to one of four experimental rations for the duration of gestation. Experimental diets were formulated in a factorial design with two levels of energy (HE = high, ME = moderate) and protein (HP = high, MP = moderate). Only females on the HEHP diet gained weight during gestation. Moderate restrictions of energy or protein had no influence on the number of young born alive, litter size, litter weight and length of gestation. Foetal development was only minimally affected by prolonged restrictions in protein intake. This study suggests that nutrition‐related prenatal mortality between implantation and parturition may not be the most important mechanism limiting herd recruitment during moderate periods of drought in southern Texas.

Breast-Feeding Among Teenage Mothers

Information on breast-feeding was obtained from 25 mothers recruited from four high school programs for teenaged parents. Subjects were visited monthly 1-9 times (mean 3.7 visits) during the first 10 months of lactation to measure infant growth and maternal dietary intake and to collect a breast milk sample. Of 24 mothers visited more than once, 21 (88%) breast-fed for more than 3 months, and at least nine continued beyond 6 months. Compared to the nutrient content of milk samples from adult women, milk of teenage mothers was significantly lower in lactose, magnesium, calcium, potassium, and sodium. However, the differences in magnesium, calcium, and potassium may have been due to differences in the timing of sample collection. On the basis of infant growth, milk volume was judged to be adequate for 88% of the infants. Mean maternal energy and protein intakes were 2,897 kcal and 115 g, respectively; mean intakes of calcium, potassium, vitamin A, riboflavin, niacin, and vitamin C exceeded the National Research Council's Recommended Dietary Allowances (RDA) for lactation, while iron and thiamine intakes averaged 84% and 94% of the RDA, respectively. It is concluded that with active counseling teenage mothers are capable of successful lactation.

Breast‐Feeding Among Teenage Mothers

Information on breast‐feeding was obtained from 25 mothers recruited from four high school programs for teenaged parents. Subjects were visited monthly 1–9 times (mean 3.7 visits) during the first 10 months of lactation to measure infant growth and maternal dietary intake and to collect a breast milk sample. Of 24 mothers visited more than once, 21 (88%) breast‐fed for more than 3 months, and at least nine continued beyond 6 months. Compared to the nutrient content of milk samples from adult women, milk of teenage mothers was significantly lower in lactose, magnesium, calcium, potassium, and sodium. However, the differences in magnesium, calcium, and potassium may have been due to differences in the timing of sample collection. On the basis of infant growth, milk volume was judged to be adequate for 88% of the infants. Mean maternal energy and protein intakes were 2,897 kcal and 115 g, respectively; mean intakes of calcium, potassium, vitamin A, riboflavin, niacin, and vitamin C exceeded the National Research Council'S Recommended Dietary Allowances (RDA) for lactation, while iron and thiamine intakes averaged 84% and 94% of the RDA, respectively. It is concluded that with active counseling teenage mothers are capable of successful lactation.

Studies on the energy metabolism of the pregnant sow. 1. Uterus and mammary tissue development.

Twenty-six gilts were used in an experiment to study the effects of level of feed intake on the growth and chemical composition of the gravid uterus and mammary tissue at several stages of gestation. The animals were given either 1.8 or 2.5 kg feed/d (20 or 30 MJ metabolizable energy (ME) respectively) and were slaughtered at intervals between days 40 and 110 of gestation. The gravid uterus was dissected into fetal, placental, fluid and empty uterus components. From day 70 of gestation the mammary tissue was also dissected. The fresh weight and dry matter (DM), energy and nitrogen contents of the various tissues were determined. With the exception of the fluid component, there was a significant increase (P less than 0.01) in the fresh weight of each tissue with both stage of gestation and level of feeding. At comparable litter sizes the total weight of the fetuses in late gestation was 16% higher with the higher feed intake. The DM content of the individual uterine tissues increased significantly (P less than 0.01) with increase in stage of gestation so that the mean DM content of the gravid uterus increased from 74.6 g/kg at day 50 to 103.1 and 159.0 g/kg at days 90 and 110 of gestation respectively. Neither stage of gestation nor feeding level influenced the respective energy contents of the individual uterine tissues, when expressed per g DM. The mean energy content of the total gravid uterus was 19.5 kJ/g DM. The N content (g/g fresh weight) of the tissues increased with stage of gestation and was generally higher at the higher feeding level. The mean N contents (g/g DM) of the fetal, placental, fluid and empty uterine tissues were 0.090, 0.101, 0.098 and 0.128 respectively. The mammary tissue was the most variable of all the tissues investigated. Whereas the fresh weight and N content increased with stage of gestation, both the DM and energy content decreased. Gompertz equations were fitted to describe the effects of stage of gestation, level of feed intake and liter size on the fresh weight and chemical content of the individual uterine tissues, total gravid uterus and mammary tissue. The use of these equations for calculating the nutrient requirements of pregnancy is demonstrated. It was calculated that between days 50 and 110 of gestation the ME requirement for reproduction increased from 3 to 12% of maternal energy intake. The calculated requirement for protein was from 7 to 41% of maternal dietary protein intake respectively.

Effects of diet and obesity on body weight regulation during pregnancy and lactation in the rat

The effects of obesity level and cafeteria feeding were studied in rats during pregnancy and lactation. The non-fetal weight gain in pregnancy was three times greater with the cafeteria diet than with chow, indicating that fat deposition is not regulated at an optimal level during pregnancy. There was a strong negative correlation between postpartum weight and weight change during lactation. Obese rats were finicky in that their weight changes in lactation were exaggerated when the diet was changed between pregnancy and lactation. Pup growth rate was proportional to maternal energy intake but in this experiment not related to maternal protein, fat or carbohydrate intake. In obese rats switched to chow, intake was inadequate for normal pup growth. Thus, the weight gains in pregnancy are not regulated at a set level, and the weight change in lactation appears to compensate for the weight gain in pregnancy.

Altered Brown Adipose Tissue Mitochondrial Function in Neonates Born to Rats Overfed Foods of Various Protein Content

On day 3 of pregnancy, 20 female Sprague-Dawley rats were randomly divided into four groups and fed either a powdered, control diet containing 27% casein (control) or “cafeteria” diets of low (7%, LP), normal (26%, NP) or high (35%, HP) protein content throughout gestation. Maternal gross energy intake was significantly increased 35% in each of the cafeteria-fed groups compared to control. At birth, mean body weight of the offspring in each diet group was not significantly different, whereas brown adipose tissue (BAT) weight and mitochondrial function (unrestricted minus GDP-inhibited anion conductance) were significantly decreased in LP offspring and increased in NP and HP offspring when compared to controls. Maternal diet composition, therefore, can alter neonatal BAT mitochondrial function and, perhaps, thermogenic capacity independent of total energy intake during pregnancy.