Also see:
Sodium Deficiency in Pre-eclampsia
Nutrition and Brain Growth in Chick Embryos
PUFA, Development, and Allergy Incidence
“Sodium is required for cells to cells to absorb glucose and amino acids.
…
In the fetus and newborn baby, sodium promotes growth. Progesterone, sodium, and glucose are limiting factors in the growth of the baby’s brain; whey they are deficient, cells die instead of growing.
The fact is the sodium energizes. It helps to remove calcium from the cell, to produce ATP, and to promote absorption of glucose and amino acids.” -Ray Peat, PhD
Pediatr Nephrol. 1993 Dec;7(6):871-5.
The influence of sodium on growth in infancy.
Haycock GB.
Sodium (Na) is an important growth factor, stimulating cell proliferation and protein synthesis and increasing cell mass. Sodium chloride (NaCl) deprivation inhibits growth, as reflected by reduced body and brain weight, length, muscle and brain protein and RNA content and brain lipid content compared with controls. This is not due to deficiency of other nutrients since control and experimental diets were identical except for NaCl content. Subsequent NaCl supplementation restores growth velocity to control values but does not induce “catch-up” growth. In humans, salt loss causes growth failure and subsequent salt repletion improves growth. Preterm infants < 32 weeks’ gestation at birth are renal salt losers in the first 2 weeks of post-natal life and are vulnerable to hyponatraemia. This can be prevented by increasing Na intake, which also produces accelerated weight gain that persists beyond the period of supplementation. Early nutrition in preterm infants can affect subsequent growth and also cognitive function: this is probably multifactorial, but NaCl intake differed substantially between study groups and is likely to be an important factor. The mechanism whereby Na promotes cell growth is not understood, but stimulation of the membrane Na+,H(+)-antiporter with alkalinization of the cell interior is a likely possibility.
Arch Dis Child Fetal Neonatal Ed. 2002 March; 86(2): F120–F123.
Effect of salt supplementation of newborn premature infants on neurodevelopmental outcome at 10–13 years of age
J Al-Dahhan, L Jannoun, and G Haycock
Background: The nutritional requirements of prematurely born infants are different from those of babies born at term. Inadequate or inappropriate dietary intake in the neonatal period may have long term adverse consequences on neurodevelopmental function. The late effect of neonatal sodium deficiency or repletion in the premature human infant on neurological development and function has not been examined, despite evidence in animals of a serious adverse effect of salt deprivation on growth of the central nervous system.
Methods: Thirty seven of 46 children who had been born prematurely (gestational age of 33 weeks or less) and allocated to diets containing 1–1.5 mmol sodium/day (unsupplemented) or 4–5 mmol sodium/day (supplemented) from the 4th to the 14th postnatal day were recalled at the age of 10–13 years. Detailed studies of neurodevelopmental performance were made, including motor function and assessment of intelligence (IQ), memory and learning, language and executive skills, and behaviour. Sixteen of the children were found to have been in the supplemented group and 21 in the unsupplemented group.
Results: Children who had been in the supplemented group performed better in all modalities tested than those from the unsupplemented group. The differences were statistically significant (analysis of variance) for motor function, performance IQ, the general memory index, and behaviour as assessed by the children’s parents. The supplemented children outperformed the unsupplemented controls by 10% in all three components of the memory and learning tests (difference not significant but p < 0.1 for each) and in language function (p < 0.05 for object naming) and educational attainment (p < 0.05 for arithmetic age).
Conclusions: Infants born at or before 33 weeks gestation require a higher sodium intake in the first two weeks of postnatal life than those born at or near term, and failure to provide such an intake (4–5 mmol/day) may predispose to poor neurodevelopmental outcome in the second decade of life.
