Benefits
Faster, more accurate attention-test scores 1 to 3 hours after a dose
In a randomized, double-blind trial of 96 working adults aged 35 to 65, 250 mg of the extract in water beat placebo on reaction time, correct answers and errors in computerized attention, symbol-coding and Stroop tests at 1 and 3 hours on the first day (p<0.05). The trial's later paper found fewer first-day differences. Caffeine (200 mg) produced larger changes on several measures. The maker funded the trial.
Attention and processing-speed gains held over 14 days of daily use
In the same trial, people took one sachet a day for 14 days, and 85 of 96 finished. On day 14 the extract still beat placebo on attention, symbol-coding and Stroop tests at 1, 3 and 5 hours, and on some of them at 8 hours. These are laboratory test scores in working adults, not measures of work, study or driving performance.
With caffeine, the combination kept attention-test gains the longest
In the same trial, the group taking the extract with 200 mg of caffeine showed the most differences from placebo at the 5 and 8 hour checks, especially on day 14. The papers compared each group with placebo and did not test whether the combined effect was more than the two added together. No caffeine crash or comedown was measured.
Mechanism of action
Proposed effects on brain signaling and oxidative stress
The trial authors propose that saponins, polyphenols and 1,8-cineole in the extract act on brain signaling chemicals such as acetylcholine and on oxidative stress, citing laboratory and animal research. Neither trial paper measured any blood or brain marker, so why the test scores changed is unknown.
BDNF and brain protection claims
No study cited on this page measured BDNF, neurotransmitters or brain protection in people. In one animal study, a methanol extract of black cardamom fruit (not this branded water extract) lowered oxidative stress and inflammation markers in the liver, kidneys and lungs after the drug methotrexate. It did not look at the brain.
Why the combination with caffeine lasted longer
The extract plus caffeine group differed from placebo at later time points than either alone. Why is not known. The first trial paper suggests the extract may slow caffeine breakdown (CYP1A2), but neither paper measured caffeine levels, and neither tested whether the combined effect was more than additive.
Water extraction and how black cardamom differs from green
The maker uses a water-based extraction; the first trial paper calls MA2-24 patented and the second calls it patent pending. A lab comparison found distinct chemical profiles in black and green cardamom seed and husk, so research on green cardamom does not transfer to this extract.
Clinical trials
Randomized, double-blind, placebo- and active-controlled, four-arm parallel trial (registry CTRI/2024/09/074472) of 250 mg MA2-24 (CardaMind) once daily for 14 days, with CNS Vital Signs tests at 1, 3, 5 and 8 hours after the dose on days 1, 7 and 14. The day 1 results were published first as a separate paper under the same registry number with the same 96 participants and product batches, so both papers describe one trial; their day 1 statistics differ. Funded by Akay Natural Ingredients, the maker; three authors are Akay employees and the first author works for a clinical research company. (Thomas et al. 2026, Front Neurosci)
96 working adults aged 35 to 65 (59 men, 37 women) with a Fatigue Severity Scale score above 4, 24 per group: placebo, 250 mg extract, 200 mg caffeine, or extract plus caffeine. 85 completed the 14 days.
On day 1 the first paper reports the extract beat placebo on attention, symbol-coding and Stroop scores at 1 and 3 hours (p<0.05), with caffeine larger on several measures; the 14-day paper's own day 1 analysis found no extract effect on attention-test errors at 1 and 3 hours or on Stroop at 3 hours. By day 14 the extract beat placebo on all seven scores at 1, 3 and 5 hours and on four at 8 hours. The extract plus caffeine showed the most differences from placebo at 5 and 8 hours. No adverse events were reported with the extract alone.