Ingredient encyclopedia · Active botanicals

Heartleaf

Heartleaf extract is investigated in skincare for hydration and surface oiliness. A small eight-week toner study reported improvements in these measurements, but its detailed results deserve a more careful reading than the headline promises. The preparation matters as much as the plant name.

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The plant behind the name

Heartleaf is Houttuynia cordata, a member of the Saururaceae family. Its native range extends from the Himalaya through temperate eastern Asia and Indochina. It is a perennial with underground stems, rather than a tea species or a type of Centella. A native range describes botanical distribution; it does not identify where the ingredient in a particular bottle was grown.

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A mixture, not one “soothing molecule”

Heartleaf contains several related flavonoids. In a 2023 analytical investigation, researchers measured rutin, hyperin, isoquercitrin, quercitrin and quercetin in 32 fresh-leaf samples and four powder products. These are individual chemical names within a wider plant mixture, not five interchangeable names for the extract.

The useful contribution of this work is a chemical fingerprint: instruments can distinguish and measure selected constituents instead of treating every green powder as identical. The analysis does not establish how much of each molecule reaches living skin from a finished toner, or which constituent would explain a clinical change.

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What “flavonoid” and “extract” mean

A flavonoid belongs to a large family of plant molecules with related ring-shaped carbon frameworks. Small differences in attached groups can change how a molecule interacts with water, oils and proteins. A family name is therefore a chemical description, not a single skincare action.

An extract is a selected mixture obtained from plant material. Changing the extraction liquid changes which substances move out of the plant. Removing that liquid can produce a dry extract; dissolving the material again produces a liquid ingredient. Neither the original leaf nor every extracted preparation has one universal composition.

For example, one documented cosmetic heartleaf extract is supplied in water and butylene glycol. The ingredient added to a cream therefore includes a carrier as well as botanical material. Butylene glycol is not another name for heartleaf, and a percentage of this liquid is not a percentage of pure flavonoids.

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A different identity appears on a widely marketed “77% heartleaf” toner: its botanical ingredient is listed as Houttuynia Cordata Flower/Leaf/Stem Water. The complete formula also lists glycerin, betaine, butylene glycol, panthenol and other ingredients. That label percentage should not be read as 77% isolated plant actives. A botanical water and a concentrated dry extract are different preparations, even when both feature the same plant prominently.

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Conceptual identity guide, not a composition chart. A percentage needs a clearly defined material before it can be compared with another percentage.

Why researchers are interested

Phosri and colleagues compared aqueous and ethanolic extracts of dried aerial parts in 2022. Their phenolic and flavonoid assay results differed, and laboratory tests found inhibition of enzymes associated with breakdown of collagen, elastin and hyaluronic acid. They also examined activity against Cutibacterium acnes in culture.

What these laboratory tests can tell us

They help identify preparations worth investigating. They do not show that applying a toner prevents wrinkles or treats acne. An enzyme in a test vessel and bacteria in a culture are not a whole skin barrier. “Quercetin equivalents” in a total-flavonoid assay describe comparison with a reference standard, not the percentage of pure quercetin in the extract.

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A 2024 experiment made this preparation question more specific. Researchers adjusted an ethanol-and-salt extraction system, using ultrasound, to enrich two flavonoids: hyperin and quercitrin. They measured these molecules and tested the resulting extract against bacterial cultures. This links a processing choice with a measurable chemical change rather than assuming all heartleaf extracts behave alike.

Despite “towards acne treatment” in the paper’s title, this was extraction and laboratory antibacterial research, not a trial showing fewer acne lesions in people. Its most useful skincare lesson is that an extract has a chemical history, and that history affects what is actually being tested.

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The human toner study: promising, with important limits

In 2023, sixteen screened volunteers were randomized into two groups using toner with or without extract once daily for eight weeks. Surface sebum and hydration were measured. The extract group showed favorable changes, while the extract-free toner also improved hydration.

Read the comparisons carefully

The published tables emphasize within-group comparisons against baseline, and the groups began with different hydration readings. Those analyses do not by themselves demonstrate a reliable difference between treatments. With eight people per group and unclear efficacy blinding, this is preliminary evidence—not a basis for precise oil-control multipliers or claims that heartleaf treats acne.

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Oiliness and hydration are not opposite ends of one scale

Surface oil and water in the outer skin layer are different things. An oiliness measurement asks about sebum at the surface; a hydration measurement asks about water-related properties of skin. A product can change one without changing the other, so “moisturizing” need not mean “oilier.”

The most informative way to understand heartleaf is to keep those separate outcomes connected to the tested preparation. Its chemistry offers plausible reasons for research, and the early human results are worth following. The useful evidence is the actual comparison—not the size of a botanical percentage on the front of a bottle.