Five ingredients. Twenty-four studies. Zero guesswork.

What it does. Adenosine builds up in the brain while you're awake and signals drowsiness. Caffeine blocks its receptors, which keeps neurons firing and indirectly raises dopamine and norepinephrine signalling. The felt result is better alertness, vigilance and reaction time.

What the research shows. The International Society of Sports Nutrition's 2021 position stand concludes caffeine improves attention and vigilance in most people, with effects starting at roughly 2mg per kg of body weight. A 2016 review in Neuroscience & Biobehavioral Reviews found low-to-moderate doses (about 40–300mg) reliably improve vigilance, attention and reaction time, especially when you're tired. In a 22-person crossover trial, 150mg of caffeine — the exact amount in a can of Void — improved digit-vigilance reaction time and rapid visual processing accuracy, and reduced self-rated mental fatigue.

Why 150mg. For a 75kg adult, 150mg is about 2mg/kg: the low end of the effective range, roughly a strong cup of coffee. It's enough to sharpen attention without pushing heart rate and jitters, and it leaves room in the day. The FDA considers up to 400mg a day generally safe for healthy adults; one can is 37.5% of that.

Timing. Effects begin in 15–30 minutes, peak between 30 and 120 minutes, and the half-life is 4–6 hours — so keep it out of the 6 hours before bed.

REFERENCES

1. Guest NS et al. (2021). ISSN position stand: caffeine and exercise performance. J Int Soc Sports Nutr 18:1. doi:10.1186/s12970-020-00383-4
2. McLellan TM, Caldwell JA, Lieberman HR (2016). A review of caffeine's effects on cognitive, physical and occupational performance. Neurosci Biobehav Rev 71:294–312. PMID 27612937
3. Haskell CF et al. (2008). The effects of L-theanine, caffeine and their combination on cognition and mood. Biol Psychol 77(2):113–122. doi:10.1016/j.biopsycho.2007.09.008
4. Owen GN et al. (2008). The combined effects of L-theanine and caffeine on cognitive performance and mood. Nutr Neurosci 11(4):193–198. doi:10.1179/147683008X301513

What it does. Theanine crosses the blood–brain barrier and increases alpha-band brain activity — the frequency associated with relaxed alertness. It modestly raises GABA, glycine and dopamine and blunts the body's sympathetic stress response (heart rate, salivary IgA). Unlike a sedative, it promotes calm without drowsiness.

What the research shows. A 2026 meta-analysis in Molecular Psychiatry pooled 31 randomised trials (1,168 people). A single 200mg dose taken 30–60 minutes before testing improved choice reaction time (effect size 0.51) and modestly reduced acute stress; no serious adverse events were reported. In a 4-week trial, 200mg a day improved trait anxiety, sleep quality, verbal fluency and executive function versus placebo. Under a mental-arithmetic stressor, 200mg blunted the rise in heart rate and stress markers.

Why it's paired with caffeine. This is the best-replicated pairing in the formula. 150mg caffeine plus 250mg theanine — almost exactly Void's ratio — produced faster reaction times, better accuracy, higher alertness and lower headache and fatigue than placebo. Lower doses (40–50mg caffeine with 97–100mg theanine) improved task-switching accuracy and reduced distractibility compared with caffeine alone, with only a ~3 mmHg rise in systolic blood pressure.

Why 200mg. 200mg is the single most-studied dose in the literature and matches Void exactly. Onset is 30–60 minutes; the alpha-wave effect lasts 2–3 hours.

REFERENCES

1. Gerolymos C et al. (2026). Cognitive and affective effects of L-theanine: a systematic review and meta-analysis of 31 randomized trials. Mol Psychiatry. doi:10.1038/s41380-026-03727-9
2. Hidese S et al. (2019). Effects of L-theanine administration on stress-related symptoms and cognitive functions in healthy adults. Nutrients 11(10):2362. doi:10.3390/nu11102362
3. Kimura K et al. (2007). L-theanine reduces psychological and physiological stress responses. Biol Psychol 74(1):39–45. doi:10.1016/j.biopsycho.2006.06.006
4. Haskell CF et al. (2008). Biol Psychol 77(2):113–122. doi:10.1016/j.biopsycho.2007.09.008
5. Giesbrecht T et al. (2010). The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness. Nutr Neurosci 13(6):283–290. doi:10.1179/147683010X12611460764840
6. Owen GN et al. (2008). Nutr Neurosci 11(4):193–198. doi:10.1179/147683008X301513

What it does. Alpha-GPC (L-alpha-glycerylphosphorylcholine) is a phospholipid-bound form of choline that crosses the blood–brain barrier and supplies the raw material for acetylcholine — the neurotransmitter of attention, learning and muscle activation. 400mg delivers roughly 160mg of choline, about 29% of the adult Adequate Intake.

What the research shows. In a 2021 placebo-controlled trial, 39 healthy adults took 400mg a day — Void's exact dose — for two weeks; motivation scores measured in the evening were significantly higher than placebo, with no adverse events across a 12-month follow-up. A small pilot in resistance-trained men found 600mg taken 90 minutes before exercise raised peak bench-press force 14% versus placebo. A 2017 randomised trial compared 250mg and 500mg daily on strength, reaction time and mental arithmetic.

Honest framing. Trials in healthy adults are small and several are industry-funded; the largest body of evidence is in clinical populations at higher doses, which we cite only for mechanism, not as a claim. Void's 400mg sits inside the 250–600mg range used in the healthy-adult studies.

Timing. Plasma choline rises within 1–2 hours; pre-exercise studies dosed 60–90 minutes ahead.

REFERENCES

1. Tamura Y et al. (2021). Alpha-glycerylphosphorylcholine increases motivation in healthy volunteers. Nutrients 13(6):2091. doi:10.3390/nu13062091
2. Ziegenfuss T, Landis J, Hofheins J (2008). Acute supplementation with alpha-glycerylphosphorylcholine augments growth hormone response to, and peak force production during, resistance exercise. J Int Soc Sports Nutr 5(S1):P15. doi:10.1186/1550-2783-5-S1-P15
3. Marcus L et al. (2017). Evaluation of the effects of two doses of alpha glycerylphosphorylcholine on physical and psychomotor performance. J Int Soc Sports Nutr 14:39. doi:10.1186/s12970-017-0196-5
4. Sagaro GG, Traini E, Amenta F (2023). Activity of choline alphoscerate on adult-onset cognitive dysfunctions: a systematic review and meta-analysis. J Alzheimers Dis 92(1):59–70. doi:10.3233/JAD-221189

What it does. Tyrosine is the amino-acid precursor of dopamine and norepinephrine. Under acute stress, noise, cold or sleep loss these catecholamines are used faster than they're replenished; extra tyrosine helps sustain synthesis so working memory and cognitive control hold up. In a rested, unstressed brain it does little — the enzyme that converts it is already saturated.

What the research shows. A 2015 systematic review in the Journal of Psychiatric Research concluded tyrosine effectively enhances cognitive performance in short-term stressful or cognitively demanding situations, with no benefit when the system isn't under load. In a 22-person trial, a 2g dose raised accuracy on a demanding 2-back working-memory task from 86.5% to 91.4%, with no effect on the easy version. Cadets given tyrosine during a one-week combat course performed better on memory and tracking tasks and had lower systolic blood pressure than placebo.

Honest framing. Most positive trials used 2g or more; military studies used 7–10g. Void's 1,000mg is below those acute doses, so we describe it as a meaningful amount of the catecholamine precursor rather than claiming the trial results. It's included because the use case — long, demanding sessions — is exactly where tyrosine has been shown to matter.

Safety. Well tolerated in short studies up to 12g a day. Talk to a clinician if you take MAO inhibitors, levodopa or thyroid medication.

REFERENCES

1. Jongkees BJ, Hommel B, Kühn S, Colzato LS (2015). Effect of tyrosine supplementation on clinical and healthy populations under stress or cognitive demands — a review. J Psychiatr Res 70:50–57. doi:10.1016/j.jpsychires.2015.08.014
2. Colzato LS, Jongkees BJ, Sellaro R, Hommel B (2013). Working memory reloaded: tyrosine repletes updating in the N-back task. Front Behav Neurosci 7:200. doi:10.3389/fnbeh.2013.00200
3. Deijen JB et al. (1999). Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training course. Brain Res Bull 48(2):203–209
4. Hase A, Jung SE, aan het Rot M (2015). Behavioral and cognitive effects of tyrosine intake in healthy human adults. Pharmacol Biochem Behav 133:1–6. PMID 25797188

What it does. Lemon balm (Melissa officinalis) contains rosmarinic acid and triterpenes that inhibit GABA-transaminase, the enzyme that breaks down GABA — so the brain's main calming neurotransmitter lingers longer. Extracts also bind to acetylcholine receptors. In trials the net effect is increased self-rated calmness, and at some doses better attention accuracy.

What the research shows. In a 20-person crossover study, single doses of 300–900mg increased calmness (at 300 and 900mg) and improved attention accuracy (at 600mg). Before a laboratory stressor, 600mg blunted the negative-mood effects of stress; 300mg sped up mathematical processing. In two trials using lemon balm in a beverage — the closest match to a can — 300mg reduced state anxiety during a stress task. A 2024 review calls it a promising calming agent but notes trials are heterogeneous and more RCTs are needed.

Honest framing. The acute calming effects were seen at 300–600mg; Void's 200mg is below every dose tested in those trials. We include it as a traditional calming botanical that complements theanine, not as a standalone active with a proven effect at this dose.

Safety. Well tolerated; higher doses can be mildly sedating. Use caution with sedatives or thyroid medication.

REFERENCES

1. Kennedy DO et al. (2002). Modulation of mood and cognitive performance following acute administration of Melissa officinalis. Pharmacol Biochem Behav 72(4):953–964. PMID 12062586
2. Kennedy DO, Little W, Scholey AB (2004). Attenuation of laboratory-induced stress in humans after acute administration of Melissa officinalis. Psychosom Med 66(4):607–613. PMID 15272110
3. Scholey A et al. (2014). Anti-stress effects of lemon balm-containing foods. Nutrients 6(11):4805–4821. PMC4245564
4. Cases J et al. (2011). Pilot trial of Melissa officinalis L. leaf extract in volunteers with mild-to-moderate anxiety disorders and sleep disturbances. Mediterr J Nutr Metab 4:211–218. doi:10.3233/s12349-010-0045-4
5. Williams CM et al. (2024). Clinical efficacy and tolerability of lemon balm in psychological well-being: a review. Nutrients 16(20):3545. doi:10.3390/nu16203545