Est. 1956 · The Order The independent guide to oolong: the partly oxidized teas, and how to brew them. Oolong.biz
THE ORDER OF THE SEVENTH STEEP SEMPER PARTIM OXIDATUM The Order of the Seventh Steep
The Order of the Seventh Steep
OOLONG
Semper Partim Oxidatum Always partly oxidized

Tagged: caffeine

Article · Health & Science

The oolong weight-loss trials measured hours of fat-burning, not pounds

No systematic review of oolong and weight loss exists, only two small human trials. Here is what those trials, and the closest systematic review that does exist (green tea's), actually measured, in kilograms, not adjectives.

Jun 17, 2026
Article · Health & Science

Why a Green Oolong and a Heavy Roast Never Want the Same Water

The brewing guide states the temperature bands by oxidation level. Here is the extraction chemistry, measured in real studies, that makes them true.

Jun 4, 2026
Article · Brewing & Gongfu

The Pot Is Not Neutral: What Six Teapot Materials Do to the Same Oolong

Researchers brewed one oolong in six vessels, zisha and zhuni clay, stainless steel, ceramic, glass, and plastic, then measured what actually left the leaf. Clay changed the chemistry. Here is what the pore structure explains.

Mar 27, 2026
Article · science

Same Leaf, Split Into Green and Black, Kept Almost the Same Caffeine

Catechins collapsed by more than ninety percent between the two halves. Caffeine barely moved. Oxidation, the reaction that defines oolong, is not what decides how much of it ends up in the leaf.

Feb 23, 2026
Guide · Health & Science

Oolong and Health

What the published research on oolong tea actually measures, not what the label copy claims. The trial and cohort evidence on the heart, blood sugar, weight, and bone, how partial oxidation changes the chemistry those trials test, and how to read a small positive trial against a large null one.