The fish that never stops: why we work with wild skipjack
Notes on why the bonito — and not a synthetic analogue — is the source we chose, and what we mean when we say the active fraction equals 1.5 kg of fish.
Skipjack tuna — bonito, katsuo — are obligate swimmers. They have no gill cover and breathe by ramming water across their gills as they move. If they stop, they suffocate. A skipjack will swim, without pause, every day of its life.
They cruise at speeds up to 60 mph. They migrate thousands of kilometers a year. The muscle chemistry that lets them do this is the subject of a long literature in Japanese sports nutrition.
Why an extract, not a synthesis
Synthesized peptides have their place. We chose extraction because the active fraction is a profile, not a single molecule — and the profile that evolution arrived at is, by any honest reading, the one we want to start from.
Every batch is concentrated from sustainably caught wild bonito. A single serving of Katsuo Stamina — two capsules — concentrates the active peptides from roughly 1.5 kg of fish.