Cross-referencing clinical data
A pairing appears on this page only when a trial gave both ingredients together and measured the result. Chinese Sumac has none that clears that bar.
Stitching two separate single-ingredient studies into a pairing is the one thing this engine will not do. When a study of the combination itself holds up at source, it lands here with its citation.
No invented synergy. Where actives were studied on their own rather than together, the record shows each on its own evidence, never a combined effect no trial measured.
Research strength. Research strength says how much work stands behind the combination. It is never a product score.
Independent record. Every finding is cited to a named trial, dated, and never written by the brand.
20 pairings are live across the library today. Checked 20 July 2026.
No study gave these as a pair, so they are not in the card above. But the reason they belong together is settled biochemistry, not a guess, so it is worth knowing.
Chinese sumac gall material is among the richest natural sources of gallotannins, and gallotannins bind non-heme iron in the gut into complexes that resist absorption. The effect is dose related and shows up in the same meal, not days later. Anyone taking iron should put several hours between the two.
Ascorbate reduces ferric iron to the ferrous form and competes with polyphenols for the metal, which recovers part of the non-heme iron that tannins would otherwise tie up. The rescue is partial and applies to the meal in which both are eaten. It is an absorption measurement, not a change in iron status.
Tannic acid is itself a gallotannin mixture historically produced from Chinese gall, so pairing the two is stacking the same chemistry twice. Protein binding, mineral binding and gut astringency all add up rather than complement each other. Formulators should count total gallotannin rather than list two ingredients as if they were separate.
Gallotannins form insoluble complexes with proline rich and globular proteins on contact, which is what makes strong tea and unripe fruit feel dry in the mouth. In a shake this ties up both the polyphenol and part of the protein. It shows as haze, sediment and a chalky mouthfeel before it shows anywhere else.
Amylase, protease and lipase are proteins and gallotannins precipitate proteins, so enzyme activity falls in laboratory mixtures containing both. That is why high tannin plant material is described as antinutritional in animal feed work. Co-formulating the two in one capsule undercuts the enzyme claim.
Gut bacteria carrying tannase hydrolyse gallotannins into gallic acid and then into pyrogallol and other small phenolics, which are the species that actually reach circulation. People differ in whether they carry those organisms, so the same dose produces different plasma metabolites. Read this as an explanation for variability rather than a reason to combine the two products.
Gallotannins bind zinc and calcium as well as iron, though less avidly than they bind iron. In a mineral heavy formula this lowers the free cation available for uptake. Separating the doses is simpler than trying to compensate with a higher mineral amount.
EGCG carries a galloyl group and behaves much like gallotannins in binding minerals and proteins, so combining the two doubles the same chemistry rather than adding a new one. Both also share the astringency and the empty stomach gut upset. Count the galloyl load once across the formula.
Nothing specific on file for Chinese Sumac. Match the label to the daily amount above, and tell your doctor what you take.
Not medical advice. Show the label to your pharmacist.FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This information is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement regimen.