Here's the abstract of the paper, published ahead of the paper's printing:
Plasma 1-carbon metabolites and academic achievement in 15-yr-old adolescents.
Nilsson TK1, Hurtig-Wennlöf A2, Sjöström M2, Herrmann W2, Obeid R2, Owen JR2, Zeisel S2. Abstract
Academic achievement in adolescents is correlated with 1-carbon metabolism (1-CM), as folate intake is positively related and total plasma homocysteine (tHcy) negatively related to academic success. Because another 1-CM nutrient, choline is essential for fetal neurocognitive development, we hypothesized that choline and betaine could also be positively related to academic achievement in adolescents. In a sample of 15-yr-old children (n = 324), we measured plasma concentrations of homocysteine, choline, and betaine and genotyped them for 2 polymorphisms with effects on 1-CM, methylenetetrahydrofolate reductase (MTHFR) 677C>T, rs1801133, and phosphatidylethanolamine N-methyltransferase (PEMT), rs12325817 (G>C). The sum of school grades in 17 major subjects was used as an outcome measure for academic achievement. Lifestyle and family socioeconomic status (SES) data were obtained from questionnaires. Plasma choline was significantly and positively associated with academic achievement independent of SES factors (paternal education and income, maternal education and income, smoking, school) and of folate intake (P = 0.009, R2 = 0.285). With the addition of the PEMT rs12325817 polymorphism, the association value was only marginally changed. Plasma betaine concentration, tHcy, and the MTHFR 677C>T polymorphism did not affect academic achievement in any tested model involving choline. Dietary intake of choline is marginal in many adolescents and may be a public health concern.-Nilsson, T. K., Hurtig-Wennlöf, A., Sjöström, M., Herrmann, W., Obeid, R., Owen, J. R., Zeisel, S. Plasma 1-carbon metabolites and academic achievement in 15-yr-old adolescents.
From the studies I've looked at, choline is dangerous to just one group of people: men with prostate cancer. Prostate cancer cells apparently just love choline.
But for everyone else, choline is a vital nutrient for brain function, especially for children. It's so important that women have choline to give to their babies that estrogen helps females' pre-menopausal bodies make more choline. If you have a teenager, especially a boy, make sure they get enough choline!
Guess what one of the very best sources of choline is? The humble egg, until recently demonized in US nutrition and medicine. The people who make dietary recommendations have been swinging back from that stance, now grudgingly saying that one egg per day is probably OK. But a growing teenage boy needs at minimum around 2 eggs worth of choline per day. One can also get choline from beef, but there are many correlations between red meat (see recent discoveries about carnitine--which is found at very high levels in beef--and heart disease) and various diseases, so I prefer to keep our family's beef intake low. Eggs are a terrific source of nutrients for a developing body; just ask a baby chicken.