NutreeGuide — Find what actually works, backed by science

Focus & Mental Energy (work/study)

Adults wanting sharper attention and less mental fatigue during desk work.

focus

productivity

improve alertness

sustain attention

reduce mental fatigue

Core stack

Caffeine (low–moderate)

Form: coffee/tablet

Dose: 1–3 mg/kg

As needed in 1–2 sittings; avoid within 8 h of bedtime

Occasional/PRN

Why: Clear enhancement of alertness/attention at modest doses.

Sources

L-theanine + caffeine

Form: capsule

Dose: theanine mg: 100 · caffeine mg: 50

Co-ingest at start of task

Occasional/PRN

Why: Meta-analyses show improved attention and reduced jitter when combined with caffeine.

Sources