BCAAs have legitimate use with strenuous exercise particularly in caloric deficit. However they have a definite effect on neurotransmitters. They decrease norepinephrine and dopamine levels in the brain (resulting in Prolactin increase).
If they make you feel off I would lower the dose and restrict intake to workouts only.
Supplementing with essential amino acids is more interesting to me.
Psychopharmacology (Berl). 2002 Mar;160(2):192-7. Epub 2002 Jan 10.
A dose-finding study on the effects of branch chain amino acids on surrogate markers of brain dopamine function.
Gijsman HJ, Scarna A, Harmer CJ, McTavish SB, Odontiadis J, Cowen PJ, Goodwin GM.
University of Oxford, Department of Psychiatry, Warneford Hospital, Oxford OX3 7JX, UK.
RATIONALE: We have previously shown in healthy volunteers that an amino acid mixture lacking tyrosine and phenylalanine reduces tyrosine availability to the brain and produces cognitive and neuroendocrine effects consistent with reduced dopamine function. This could provide a potential nutritional approach to disorders such as mania and schizophrenia, which are characterised by overactivity of dopamine pathways. The amino acid mixture we tested previously is unpalatable, whereas mixtures containing only branch chain amino acids can be made more palatable. However, the effects of such mixtures on dopamine function in humans have not been studied. OBJECTIVE: To assess the tolerability of different doses of branch chain amino acids and to measure their effects on neuroendocrine and cognitive measures sensitive to changes in dopamine function. METHODS: We used a randomised, double-blind, cross-over design in 12 healthy volunteers to assess the effect of single oral doses of 10 g, 30 g and 60 g branch chain amino acids on plasma prolactin and a test of spatial recognition memory RESULTS: The branch chain amino acids were well tolerated. The availability of tyrosine for brain catecholamine synthesis decreased in a dose-related manner. As hypothesised, the drink increased both the plasma prolactin and the latency to respond on the spatial recognition memory task. CONCLUSIONS: A drink containing branch chain amino acids is well tolerated in healthy volunteers and produces effects consistent with lowered dopamine function.
Psychopharmacology (Berl). 2005 Jun;179(4):761-8. Epub 2005 Feb 5.
The effects of a branched chain amino acid mixture supplemented with tryptophan on biochemical indices of neurotransmitter function and decision-making.
Scarnà A, McTavish SF, Cowen PJ, Goodwin GM, Rogers RD. University Department of Psychiatry, Warneford Hospital, Oxford, OX37JX, UK.
[email protected]
RATIONALE: We have previously shown that a 60-g mixture of branched chain amino acids (BCAAs) lowers the plasma availability of the catecholamine precursors tyrosine (TYR) and phenylalanine (PHE) and produces biochemical and neuropsychological changes consistent with impaired dopamine neurotransmission. However, the BCAA mixture also lowers the ratio of tryptophan (TRP) to BCAA which could impair brain serotonin function. OBJECTIVES: To determine the biochemical and neuropsychological effects of a BCAA mixture supplemented with TRP. METHODS: We studied 32 healthy volunteers who were randomly and blindly allocated to either a single administration of amino acid mixture (60 g BCAA and 2 g TRP) or placebo. We carried out venous sampling to measure plasma levels of amino acids and performed selected cognitive tasks sensitive to monoamine manipulation 5 h after mixture ingestion. RESULTS: Relative to placebo, the BCAA/TRP mixture substantially lowered the ratio of TYR+PHE:BCAA and increased plasma prolactin. The ratio of TRP:BCAA was also lowered but to a lesser extent. The BCAA/TRP mixture produced significant changes in a task of decision-making where volunteers showed reduced discrimination between gambles with large and small losses. CONCLUSIONS: A 62 g BCAA/TRP mixture decreases the availability of TYR and PHE for brain catecholamine synthesis and increases plasma prolactin consistent with lowered brain dopamine function. Addition of 2 g TRP to the 60 g BCAA mixture does not prevent a reduction of the ratio TRP:BCAA relative to placebo. The effects of the BCAA/TRP mixture on decision-making suggest a general action of dopamine pathways on the processing of emotional information in risky choice, including punishment-related cues, consistent with suggestions that dopamine mechanisms mediate behavioural responses to aversive as well as appetitive stimuli in instrumental conditioning.