THE JOURNAL
Stories. Insights. Science.
Formulation thinking, ingredient deep-dives, and the research behind what we put in.
SLEEP QUALITY
Magnesium glycinate vs. oxide: why form matters more than dose
STRESS & CORTISOL
Ashwagandha: separating the evidence from the marketing
STANDARDS & TRANSPARENCY
The Rōnin mindset: why we called the brand Kōjō
STRESS & CORTISOL
Sleep, cortisol, and why you're wired at 11pm: the physiology of stress-disrupted sleep
STANDARDS & TRANSPARENCY
The Kōjō formula: why we built it, what we changed, and where it stands now
HORMONAL HEALTH
What happens to testosterone after 35: the evidence, without the panic
STANDARDS & TRANSPARENCY
All-in-one supplement vs. a separate stack: what the evidence says about the practical decision
STANDARDS & TRANSPARENCY
How to read a supplement facts label: what the marketing doesn't want you to notice
CARDIOVASCULAR
Omega-3 at 40: the cardiovascular and cognitive case for adequate EPA and DHA
CARDIOVASCULAR
Vitamin K2: what it actually does, and why most people are deficient
HORMONAL HEALTH
Zinc deficiency in men: the silent hormonal and immune problem most GPs don't test
COGNITIVE PERFORMANCE
L-theanine and caffeine: why the combination outperforms either alone
ALL EVIDENCE-REFERENCED, FOUNDER-WRITTEN
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Weekly research notes, formulation decisions, founder letters. No discounts, no noise - we don’t do either.