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

@article{Markus2005EveningIO,
  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},
  year={2005},
  volume={81 5},
  pages={
          1026-33
        }
}
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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References

SHOWING 1-10 OF 49 REFERENCES

Whey protein rich in alpha-lactalbumin increases the ratio of plasma tryptophan to the sum of the other large neutral amino acids and improves cognitive performance in stress-vulnerable subjects.

The results suggest that dietary protein rich in alpha-lactalbumin improves cognitive performance in stress-vulnerable subjects via increased brain tryptophan and serotonin activities.

Effects of a Tryptophan-Free Amino Acid Drink Challenge on Normal Human Sleep Electroencephalogram and Mood

The bovine protein alpha-lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids, and in vulnerable subjects raises brain serotonin activity, reduces cortisol concentration, and improves mood under stress.

Testing whether alpha-lactalbumin, a whey protein with a high tryptophan content, may increase the plasma Trp-LNAA ratio and reduce depressive mood and cortisol concentrations in stress-vulnerable subjects under acute stress found it improved coping ability.

Dose-Dependent Effect of α-Lactalbumin in Combination with Two Different Doses of Glucose on the Plasma Trp/LNAA Ratio

Investigation of the time- and dose dependent effects of α-lactalbumin enriched whey protein with a high tryptophan content in combination with two doses of glucose on plasma Trp/LNAA shows that ingestion of 20 g α- lact Albumin may be a suitable dietary method to investigate the effect of alterations in brain serotonin.

Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios.

Whether carbohydrate-rich or protein-rich breakfasts, such as those Americans normally eat, produce substantial differences in the plasma tryptophan-LNAA ratio and in the corresponding ratio for tyrosine, the precursor of brain dopamine and norepinephrine is determined.

Effects of L-tryptophan on sleepiness and on sleep.

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

Evaluation of l-tryptophan for treatment of insomnia: A review

In younger situational insomniacs, whose sleep problem consists solely of longer than usual sleep latencies, l-tryptophan is effective in reducing sleep onset time on the first night of administration in doses ranging from 1 to 15 g.

BRIEF COMMUNICATION: Sleep Induced by L-Tryptophan: Effect of Dosages within the Normal Dietary Intake

The present laboratory study extends the dose-response curve downward, comparing doses of ¼ g, ½ g, and 1 g of L-tryptophan with placebo, in 15 mild insomniacs (subjects who reported sleep latencies of over 30 minutes).