Evening intake of alpha-lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention.

  title={Evening intake of alpha-lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention.},
  author={C. Rob Markus and Lisa M. Jonkman and Jan Lammers and Nicolaas E. P. Deutz and Marielle H. Messer and Nienke Rigtering},
  journal={The American journal of clinical nutrition},
  volume={81 5},
BACKGROUND Brain serotonin function is thought to promote sleep regulation and cognitive processes, whereas sleep abnormalities and subsequent behavioral decline are often attributed to deficient brain serotonin activity. Brain uptake of the serotonin precursor tryptophan is dependent on nutrients that influence the availability of tryptophan via a change in the ratio of plasma tryptophan to the sum of the other large neutral amino acids (Trp:LNAA). OBJECTIVE We tested whether evening… 

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  • E. Hartmann
  • Psychology
    Journal of psychiatric research
  • 1982

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