Also known as: PS
Latest evidence update: 2026-03-23
Strongest in Consistency (88). Held back by Recency (46).
Solid mix of RCTs with some methodological gaps.
Good cross-study replication, some imprecision.
Thousands of participants across the literature.
Studies agree on direction of effect.
Evidence base skews older; field may have moved on.
No per-outcome numbers yet for this one. Each finding's direction and strength is shown in the research below.
Areas where research points to a consistent direction of effect. The strength of evidence is graded; the size of the effect is not quantified.
Recommended: 100-300mg daily
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Supports memory formation, retrieval, and learning ability
May reduce inattention symptoms in children with ADHD, though effects on overall ADHD symptoms are inconsistent
Supports focus, concentration, and attention abilities
May help reduce carpal tunnel syndrome pain and symptoms when combined with other nutrients
Supports healthy nerve cell structure and may slow age-related brain changes