Cross-referencing clinical data
A pairing appears on this page only when a trial gave both ingredients together and measured the result. Chard 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.
Chard leaves carry non-heme iron, which is absorbed poorly on its own. Ascorbate keeps iron in the reduced ferrous state at duodenal pH and forms a soluble complex that survives the shift out of the stomach. Eating the leaves with a citrus or pepper source, or pairing a leaf powder with added ascorbate, raises the fraction absorbed. The effect is on absorption, not on how much iron the leaf contains.
Chard is one of the higher-oxalate leafy greens. Oxalate binds divalent iron in the gut lumen and forms a poorly soluble complex, so iron eaten in the same meal is less available. This matters most for people relying on plant iron rather than supplementing away from meals. Separating an iron dose from a large chard serving by a couple of hours sidesteps most of it.
Calcium and oxalate form calcium oxalate, which is close to insoluble. Some of the calcium in chard is already locked up this way before it reaches the gut, and added calcium in the same meal binds free oxalate instead of being absorbed. The same is true in the other direction, and usefully so: calcium taken with a high-oxalate meal lowers how much oxalate reaches the kidney. Anyone with a history of oxalate stones should take that trade-off up with a clinician.
Chard is often listed as a magnesium source, but leaf oxalate binds magnesium by the same chemistry it binds calcium and iron. The magnesium number on a food table is total content, not what crosses the gut wall. Read chard as a modest magnesium contributor rather than a primary one.
Phylloquinone in green leaves sits inside the chloroplast membrane, and chard carries a lot of it per gram. Stacking a K1 supplement on top of a regular chard habit adds to the same pool that drives hepatic carboxylation. People on vitamin K antagonist therapy are told to keep intake steady rather than swing it, so a sudden change in either source is the part that matters.
Lutein, zeaxanthin, beta-carotene and phylloquinone in chard are all fat soluble and need mixed micelles to cross the enterocyte. A fat-free preparation of the leaf leaves much of that behind. Adding a few grams of any dietary lipid alongside the leaf, culinary oil included, does the job.
Chard sits with rocket, spinach and beetroot in the high-nitrate group of vegetables. Both feed the same enterosalivary nitrate to nitrite to nitric oxide route, so the intakes add rather than act separately. Someone already eating large leafy salads is starting from a higher baseline than a trial protocol assumes.
Nothing specific on file for Chard. Match the label to the daily amount above, and tell your doctor what you take.
Not medical advice. Show the label to your pharmacist.These are the studies our verdict leans on, chosen from the 1 we read for Chard. The full linked list is below.
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.