Centella Asiatica Extract

Centella Asiatica Extract (Centella) is one of the most researched botanical extracts in skincare with decades of studies backing its effects on inflammation, collagen, and the skin barrier.

That research keeps pointing back to the same four triterpenoid saponins: Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid.

These compounds allow centella to dial back inflammation, encourage the skin to build and hold onto collagen, support the barrier and hydration, and bring solid antioxidant activity to protect against signs of aging.

Centella also carries a nice supporting cast of Vitamin A, vitamin C, several B vitamins, and amino acids. Put it all together and you get an ingredient that soothes, hydrates, and protects, all at once.

How Centella works

Most of centella's magic comes from the four big compounds (Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid). These are the actives doing the heavy lifting in almost every centella study.

Here is the short version of what they do in the skin:

1. They calm inflammation. The triterpenes turn down inflammatory signaling pathways and less of this signaling means less redness and irritation.
2. They tell your fibroblasts to make more collagen. Asiaticoside in particular boosts Type I collagen and centella's triterpenes have been shown to lift collagen and fibronectin output by roughly 20 to 35% in lab studies.
3. They protect the collagen you already have. UV light switches on enzymes called MMPs that break collagen down and centella's triterpenes help keep those enzymes in check. Asiatic Acid was the strongest of the four at blocking UVB-triggered MMPs in one study.
4. They mop up free radicals. Centella's antioxidant activity in one study came in around 84%. That puts it right alongside grape seed extract (83%) and vitamin C (88%).

So it is not just soothing for the sake of soothing. Centella calms the skin AND helps it rebuild.

Benefits

1. Soothing and redness relief: This is centella's claim to fame and the anti-inflammatory research backs it up.
2. Barrier support and hydration: A centella cream significantly improved skin hydrated and lowered water loss in a double-blind trial on workers with dry, irritated hands (holding its own against a ceramide cream). A separate study also found centella helped restore the skin's own hyaluronic acid and ceramides.
3. Anti-aging: Centella is genuinely useful for fine-lines, firmness, and photoaging because it protects and builds collagen while fighting free radicals.
4. Scars and would healing: Centella has decades of use in this context; reviews of the clinical research consistently report improved scar appearance and faster wound repair. This is also why it's found in so many post-procedure formulas.
5. Post-acne marks: The same soothing and collagen-supporting properties makes it a nice pick for calming breakouts and helping marks fade.

Types and sources

Just FYI, not all centella on an ingredient list is the same. What you are getting actually depends on the extract:

• Full extract (Centella Asiatica Extract) contains the whole mix of triterpenes plus flavonoids, amino acids, and vitamins.
• TECA (titrated extract of Centella Asiatica) is a standardized blend of Asiatic Acid, Madecassic Acid, and Asiaticoside, used a lot in the more clinical formulas.
• Isolated actives show up on their own too: Asiaticoside, Madecassoside, Asiatic Acid, and Madecassic Acid.

Fun fact on the ratios: the leaves tend to be richest in Madecassoside and Asiaticoside, and lower in the two acids. The exact amounts shift with where the plant is grown and how it is processed. This means purity really does vary brand to brand.

Compatibility

Centella is one of the most easygoing actives out there.

It layers well with basically everything: niacinamide, hyaluronic acid, peptides, and vitamin C, and also pairs nicely with stronger actives like retinoids and exfoliating acids where it can help take the edge off irritation.

On the safety side, centella and its triterpenes are classified as weak sensitizers, meaning allergic reactions are possible but uncommon.

Patch tests at 1% and 5% came back negative in test panels, and creams at typical use levels did not cause allergic reactions across large groups of people.

But as with any new active, a patch test is still a smart move for very reactive skin.

Usage percentages

Centella is widely used because it is effective at low percentages. For context, human safety testing found no meaningful irritation from creams containing centella extract at everyday use levels (the tested amounts were well under 1%).

The irritancy threshold in animal testing was also above 30% (so real-world formulas sit far below anything concerning).

In collagen lab studies, higher concentrations drove more collagen synthesis, so serums built around centella tend to feature it more prominently.

Bottom line: you will find centella working nicely anywhere from a fraction of a percent up to hero-ingredient levels depending on whether it is a supporting soother or the main event.

Fun fact: Centella has been used as a medicine and in food for many centuries. As a medicine, it is used to treat burns, scratches, and wounds.