Tryptophan and its roles:

  • Involved in serotonin and melatonin production
  • Regulator of  fatigue
  • Calming effect
  • Support proteins synthesis

Tryptophan and its sources:

  • Whey protein (Casein)
  • Eggs
  • Rice
  • Banana
  • Papilionaceae (alfalfa, …)

Tryptophan is like a branched amino acid, but with benzene and azoles chemical groups. Serotonin is derived from this amino acid. It helps regulate basic activity and especially sleep.

It seems that, in equines, the apparent calming effect of tryptophan is dose dependent.  A low supply acts as a stimulant and a larger supply has a calming effect. It is also shown that a high level of tryptophan in blood can badly affect endurance effort (Alberghina et al., 2010).