May help shield the brain from the adverse effects of stress L-Tyrosine is an amino acid found in foods like wheat germ, oats, dairy, pork and poultry. It is a precursor for neurotransmitters (dopamine, norepinephrine, epinephrine) that are crucial for mood and cognitive function. It helps improve focus and alertness in stressful or demanding situations, including shift work and multi-tasking. L-Tyrosine may support healthy stress responses and mental endurance.