Study Title:

Low Vitamin C Adversely Influences Cognitive Development

Study Abstract

Background: The neonatal brain is particularly vulnerable to imbalances in redox homeostasis because of rapid growth and immature antioxidant systems. Vitamin C has been shown to have a key function in the brain, and during states of deficiency it is able to retain higher concentrations of vitamin C than other organs. However, because neurons maintain one of the highest intracellular concentrations of vitamin C in the organism, the brain may still be more sensitive to deficiency despite these preventive measures.

Objective: The objective was to study the potential link between chronic vitamin C deficiency and neuronal damage in newborn guinea pigs.

Design: Thirty 6- to 7-d-old guinea pigs were randomly assigned to 2 groups to receive either a vitamin C–sufficient diet or the same diet containing a low concentration of vitamin C (but adequate to prevent scurvy) for 2 mo. Spatial memory was assessed by the Morris Water Maze, and hippocampal neuron numbers were quantified by stereologic techniques.

Results: The results showed a reduction in spatial memory (P < 0.05) and an increased time to first platform hit (P < 0.05) in deficient animals compared with controls. The deficient animals had a lower total number of neurons in hippocampal subdivisions (dentate gyrus, cornu ammonis 1, and cornu ammonis 2–3) than did the normal controls (P < 0.05).

Conclusions: Our data show that vitamin C deficiency in early postnatal life results in impaired neuronal development and a functional decrease in spatial memory in guinea pigs. We speculate that this unrecognized effect of vitamin C deficiency may have clinical implications for high-risk individuals, such as in children born from vitamin C–deficient mothers.

From press release:

New research at LIFE – Faculty of Life Sciences at University of Copenhagen shows that vitamin C deficiency may impair the mental development of new-born babies.

In the latest issue of the well-known scientific journal The American Journal of Clinical Nutrition, a group of researchers headed by professor Jens Lykkesfeldt shows that guinea pigs subjected to moderate vitamin C deficiency have 30 per cent less hippocampal neurones and markedly worse spatial memory than guinea pigs given a normal diet. Like guinea pigs, human beings are dependent on getting vitamin C through their diet, and Jens Lykkesfeldt therefore speculate that vitamin C deficiency in pregnant and breast-feeding women may also lead to impaired development in foetuses and new-born babies.

The brain retains vitamin C

Several factors indicate that the neonatal brain, in contrast to other tissue, is particularly vulnerable to even a slight lowering of the vitamin C level. The highest concentration of vitamin C is found in the neurons of the brain and in case of a low intake of vitamin C, the remaining vitamin is retained in the brain to secure this organ. The vitamin thus seems to be quite important to brain activity. Tests have shown that mouse foetuses that were not able to transport vitamin C develop severe brain damage. Brain damage which resembles the ones found in premature babies and which are linked to learning and cognitive disabilities later in life.

Widespread vitamin C deficiency

In some areas in the world, vitamin C deficiency is very common – population studies in Brazil and Mexico have shown that 30 to 40 per cent of the pregnant women have too low levels of vitamin C, and the low level is also found in their foetuses and new-born babies. It is not yet known to what extent new-born babies in Denmark or the Western World suffer from vitamin C deficiency but a conservative estimate would be 5 to 10 per cent based on the occurrence among adults.

“We may thus be witnessing that children get learning disabilities because they have not gotten enough vitamin C in their early life. This is unbearable when it would be so easy to prevent this deficiency by giving a vitamin supplement to high-risk pregnant women and new mothers" says Jens Lykkesfeldt whose research group is currently studying how early in pregnancy vitamin C deficiency affects the embryonic development of guinea pigs and whether the damage may be reversed after birth.


Study Information

Pernille Tveden-Nyborg, Louise Kruse Johansen, Zindy Raida, Charlotte Krogh Villumsen, Jytte Overgaard Larsen, and Jens Lykkesfeldt
Vitamin C deficiency in early postnatal life impairs spatial memory and reduces the number of hippocampal neurons in guinea pigs.
Am J Clin Nutr
2009 September
From the Department of Veterinary Disease Biology (PT-N, LKJ, ZR, CKV, and JL), Faculty of Life Science and the Department of Neuroscience and Pharmacology (JOL), Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark.

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