Lorenza Colzato and her colleagues at the Universities of Leiden and Münster in Germany published new research in the Oct. 22, 2013, edition of the journal Psychological Science that is the first to prove that the amino acid tryptophan increases levels of trust in humans.
The researchers proved that tryptophan increased the levels of trust in test participants that played a money based trust game after consuming orange juice with added tryptophan. A control group that received no tryptophan was much less trusting.
Tryptophan increases the release of serotonin in the blood stream. This research and previous research have shown that serotonin induces higher levels of trust and cooperation. A video of the experiment and results can be seen here.
Tryptophan is found naturally in red meat, fish, poultry, dairy products, nuts, seeds, bananas, dates and other food. Tryptophan has been produced commercially in large quantities for use as medicines and over the counter supplements for decades.
Could tryptophan be used by salesmen to make potential clients more trusting? All it would take is a drop of tryptophan in the clients drink at the free lunch that is always provided to those who buy or influence buying.
Politicians could add tryptophan to the drinks at campaign rallies and collect more money for their campaigns from newly more trusting party supporters.
A zealot bent on perpetrating an act of terrorism could add tryptophan to a congregation’s tea or food and collect sufficient capital to fund his plan of destruction from otherwise untrusting people.
Men and women could use tryptophan to manipulate the trust of their partners or potential partners.
The researchers did not intend the use of tryptophan to be manipulative but they have opened the door to interesting sales and political opportunities.