K. Simmer

Are long-chain polyunsaturated fatty-acids essential nutrients in infancy?

We investigated whether the disparity in neural maturation between breastfed and formula-fed term infants could be corrected by the addition of fish oil, a source of docosahexaenoic acid (DHA, 22:6 omega 3), to infant formula. Healthy, term infants were randomised at birth to receive either a supplemented or placebo formula if their mothers had chosen to bottle feed. Breastfed term infants were enrolled as a reference group. Infant erythrocyte fatty acids and anthropometry were assessed on day 5 and at 6, 16, and 30 weeks of age. Visual evoked potential (VEP) acuity was determined at 16 and 30 weeks. VEP acuities of breastfed and supplemented-formula-fed infants were better than those of placebo-formula-fed infants at both 16 and 30 weeks of age (p < 0.001 and p < 0.01). Erythrocyte DHA in breastfed and supplemented-formula-fed infants was maintained near birth levels throughout the 30-week study period but fell in placebo-formula-fed infants (p < 0.001). Erythrocyte DHA was the only fatty acid that consistently correlated with VEP acuity in all infants at both ages tested. A continuous supply of DHA may be required to achieve optimum VEP acuity since infants breastfed for short periods (< 16 weeks) had slower development of VEP than infants receiving a continuous supply of DHA from either breastmilk or supplemented formula. Erythrocyte arachidonic acid (20:4 omega 6) in supplemented-formula-fed infants was reduced below that of infants fed breastmilk or placebo formula at 16 and 30 weeks (p < 0.001), although no adverse effects were noted, with growth of all infants being similar. DHA seems to be an essential nutrient for the optimum neural maturation of term infants as assessed by VEP acuity. Whether supplementation of formula-fed infants with DHA has long-term benefits remains to be elucidated.

Eating Behaviour of Children 1.5-3.5 Years Born Preterm: Parents Perceptions

Objective: To investigate parents’ perceptions of the eating behaviour of toddlers born preterm.

Erythrocyte fatty acids of term infants fed either breast milk, standard formula, or formula supplemented with long-chain polyunsaturates

The purpose of our study was to assess whether a supplement of fish oil (FO) and evening primrose oil (EPO) for formula-fed infants was capable of avoiding reductions in erythrocyte docosahexaenoic acid (DHA, 22∶6n−3) and arachidonic acid (AA, 20∶4n−6) associated with standard formula feeding. Healthy, term infants, whose mothers chose to formula feed, were randomized to either a placebo or supplemented formula for their first 30 wk of life. A reference group of beast-fed infants also was enrolled. Erythrocyte fatty acids were measured by capillary gas chromatography on day 5 and in weeks 6, 16, and 30. Supplementation of formula with 0.36% of total fatty acids as DHA resulted in erythrocyte DHA being maintained at or above breast-fed levels for the entire 30-wk study period, and breast feeding (0.21% DHA) resulted in a modest fall in erythrocyte DHA relative to baseline (day 5) values. The level of erythrocyte DHA in placebo formula-fed infants was halved by week 16. AA levels decreased in all infants in the first six weeks, but the levels in breast- and placebo formula-fed infants increased with age and returned to approximate baseline (day 5) values by 16 and 30 wk of age, respectively. Erythrocyte AA in FO+EPO-supplemented infants remained low and below breast- and placebo formula-fed levels. Our data suggest that dietary supplementation with DHA at 0.36% total fatty acids results in erythrocyte DHA levels above those found in breast-fed infants. EPO supplementation was not effective at maintaining erythrocyte AA when given with FO.

Ratios of linoleic acid to α-linolenic acid in formulas for term infants

Commercial infant formulas with a ratio of linoleic acid (LA) to a-linolenic acid (ALA) of 10:1 or higher are nutritionally inadequate; the tissue levels of docosahexaenoic acid (DHA) are lower and the visual function indices are reduced in infants who are fed these formulas. All the evidence points to using LA:ALA ratios of less than 8:1, but there has been only one study in infants that used formulas with reduced LA:ALA ratios, and only biochemical indices were monitored. There is a need for both short-term studies to establish the ratios of LA to ALA that will make possible the accumulation of DHA to levels close to those in breast-fed infants and long-term trials to determine the effects of such fat blends on growth and development.

Essential fatty acid deficiency in parenterally fed preterm infants

To determine the incidence of essential fatty acid (EFA) deficiency during short term fat‐free parenteral nutrition, the authors investigated prospectively the EFA status of nine low birthweight (1145 ± 343 g) preterm (28.2 ± 1.9 weeks) infants, in whom delivery of dietary fat was delayed postnatally for 2–9 days. Serial determinations of plasma fatty acids showed that during fat‐free alimentation, the major EFA, linoleic acid (LA), decreased rapidly (‐0.75% total fatty acids per day), accompanied by a rise in endogenously produced non‐essential fatty acid, eicosatrienoic acid (Mead acid). Essential fatty acid deficiency was confirmed biochemically by an elevation in the triene‐tetraene ratio in six of the infants, only one of whom developed clinical symptoms. Abnormal fatty acid profiles were corrected within a few days of fat delivery by either intravenous or enteral routes.

The use of breastmilk in a neonatal unit and its relationship to protein and energy intake and growth

A nutritional audit was performed to determine whether current feeding regimes were achieving nutritional goals and to evaluate the use of breastmilk (BM) in a neonatal unit (NNU).

Aluminium concentrations in infant formulae

Abstract The aluminium concentrations in breast milk and in 25 commercially available infant formulae were measured. The mean concentration in breast milk was 49 μg/L while concentrations in most of the humanized formulae were less than 500 μ/L. Higher concentrations were found in Nan, Prem Enfamil and the three soya formulae.

Indicators of selenium status in Australian infants.

Objective: To provide the first Australian data for the commonly used indicators of selenium (Se) status including plasma and erythrocyte Se and erythrocyte glutathione peroxidase (GSHPx) activity in newborn term and preterm infants from Adelaide, South Australia. Plasma Se levels from adults from Adelaide and Tasmania are also reported.

Glutathione Peroxidase is Not a Functional Marker of Selenium Status in the Neonatal Period

BACKGROUND The antioxidant enzyme glutathione peroxidase is a selenoprotein that, in adults with low selenium intakes, has a strong linear relationship with blood selenium and hence is used as a functional indicator of selenium status. Our aim was to evaluate glutathione peroxidase as a functional marker of selenium status in preterm infants. METHODS Erythrocyte glutathione peroxidase activity and plasma and erythrocyte selenium were measured between days 1-5 and then weekly until discharge in 63 preterm infants with mean +/- standard error birth weight and gestation of 1572+/-60g and 30.7+/-0.3 weeks. A healthy reference group of term infants (n = 46) was assessed at day 5 and at 6 weeks. RESULTS In preterm infants, over the first 3 months, the association of glutathione peroxidase activity with erythrocyte selenium was weak and inconsistent and nonexistent with selenium intake or plasma selenium. No correlations between any of these indicators were evident for term infants. In preterm infants, plasma and erythrocyte selenium declined over the first 6 weeks (p < 0.01), while glutathione peroxidase activity increased (p < 0.05). In term infants, plasma selenium increased (p < 0.001), but there was no change in erythrocyte selenium or glutathione peroxidase activity. For preterm infants, glutathione peroxidase activities at weeks 4 and 6 were associated with maximum inspired oxygen concentration, ventilator pressure, and days of ventilation. CONCLUSIONS This data is consistent with animal and in vitro evidence that glutathione peroxidase may be confounded by oxygen. We conclude that erythrocyte glutathione peroxidase activity is not a reliable functional marker of preterm selenium status in the neonatal period.

How appropriate are commercially available human milk fortifiers

A preliminary investigation was made into the effectiveness of two breastmilk fortifiers on the Australian market (FM‐85 [Nestle, Vevey, Switzerland] and Enfamil Human Milk Fortifier [EHMF; Mead Johnson, Evansville, IN, USA]). Infants < 1800 g and < 34 weeks gestation at birth, who were receiving breast milk, were randomized to receive either of the fortifiers (n= 14 for FM‐85, n= 10 for EHMF), until a weight of 2 kg was reached. Infants not receiving breast milk (n= 9) were fed a preterm formula (Prenan, Nestlé). The two fortifier groups were similar in most parameters examined: (i) weight gain (17.9 ± 3.0 vs 17.4 ± 3.5g/kg per day); (ii) head circumference growth (1.02 ± 0.28 vs 1.03 ± 0.25 cm/week); (iii) arm muscle area growth (32.6 ± 20.0 vs 33.5 ± 13.7 mm2/week); (iv) arm fat area growth (14.3 ± 6.1 vs 14.0 ± 8.7 mm2/week); (v) plasma calcium (2.52 ± 0.08 vs 2.58 ± 0.15 mmol/L); (vi) plasma phosphate (2.02 ± 0.21 vs 2.13 ± 0.32 mmol/L); (vii) plasma copper (5.28 ± 2.83 vs 5.66 ± 3.07 pmol/L); and (vii) plasma zinc (13.3 ± 5.5 vs 15.8 ± 9.2 μmol/L). The FM‐85 group had a higher alkaline phosphatase level (355 ± 110 vs 231 ± 70 iu/L) than the EHMF group; however, no values were outside the normal range. The Prenan group had a higher rate of weight gain (23.6 ± 3.3 g/kg per day) and higher arm fat area growth rate (25.2 ± 7.6 mm2/week) than the fortifier groups, while all other parameters were similar. The incidence of feed intolerance was considered high in both fortifier groups. The addition of many of the components of breastmilk fortifiers has not been well validated and it is proposed that a simplified fortifier composed of protein and phosphate may be better tolerated and equally effective at optimizing growth and bone mineralization. The specific needs of extremely low birthweight infants (>1000 g) have not been addressed.