Lemon Balm

The points come from three separate placebo-controlled trials of lemon balm extract alone, not from one trial comparing all doses. In a crossover of 18 healthy adults given single doses during a laboratory stressor, 600 mg raised self-rated calmness and eased the stressor's negative mood effects but also lowered alertness, while for 300 mg the abstract reports no mood effect, only faster mathematical processing (PMID 15272110). In 60 adults with type 2 diabetes and depressive symptoms, 700 mg a day of hydroalcoholic extract for 12 weeks lowered depression and anxiety scores more than placebo, with no difference in blood pressure or sleep quality (PMID 37131158, 44 completed). In 71 adults with benign palpitations, 500 mg twice a day of lyophilised aqueous extract for 14 days reduced the number of anxious patients compared with placebo, with no serious side effects (PMID 25680840, 55 completed). The extracts differ and so do the populations and scales, so the curve is drawn flat from 600 mg: the trials cannot show that more works better. No optimal dose has been established, and nothing above 1,000 mg of extract a day was tested alone. A lemon balm and valerian combination raised anxiety at its highest single dose (PMID 16444660), which cannot be credited to lemon balm alone.