I approach supplements with extreme skepticism. Most nootropics I have tried produced either nothing measurable or placebo effects that evaporated once I stopped expecting them. I decided to give magnesium L-threonate a proper evaluation: 8 weeks of daily use at the standard 2,000mg dose, with weekly cognitive testing using Cambridge Brain Sciences (standardized tasks measuring working memory, reasoning, and verbal ability).
Setup: I established a 3-week baseline of weekly testing before starting the supplement. My baseline scores were consistent — working memory (Spatial Span) averaging 6.2, Token Search averaging 8.1, Grammatical Reasoning averaging 42.
Weeks 1-2: No measurable change in test scores. No subjective cognitive changes. Sleep perhaps marginally better but I was not tracking it systematically. I was prepared for this to be another expensive placebo.
Weeks 3-4: Spatial Span score bumped to 6.8 on week 3 and 7.1 on week 4. Could be noise — test scores fluctuate. But I noticed something subjective that I could not easily attribute to placebo: during code reviews at work, I was holding more context in my head simultaneously. I could read a function, keep its logic in working memory, and compare it against another function without needing to flip back and forth. This was a real, practical improvement in my daily work.
Weeks 5-6: Spatial Span stabilized around 7.0-7.2. Grammatical Reasoning improved to 46-48 range. Token Search did not change meaningfully. Subjectively, I noticed improved verbal fluency during meetings — I was articulating complex technical ideas more fluidly, with less of the usual stumbling over word choice.
Weeks 7-8: Scores plateaued at the new higher level. The working memory improvement (roughly 15% above baseline) has held. Sleep quality remained improved throughout.
My conclusion: the effects are real but modest. This is not a cognitive enhancement that will be obvious to an outside observer. It is a marginal improvement in baseline cognitive function that becomes noticeable primarily during demanding cognitive tasks. For me, the working memory improvement alone justifies the cost. I will continue taking it.