What Makes Calendula Work?

Calendula was one of the first medicinal herbs I ever grew, and if I'm being honest, I initially planted it because it was pretty.

The bright orange flowers looked cheerful in the garden, pollinators seemed to love them, and every herbal book I owned recommended growing it. Everywhere I looked, people described calendula as one of the best herbs for skin support, wound care, and healing.

That all sounded great, but eventually I found myself asking the same question I seem to ask about every herb these days.

Why calendula?

Why does this particular flower have such a strong reputation for cuts, scrapes, rashes, burns, and skin irritation? What is happening inside the plant that makes herbalists reach for it over and over again?

As I started studying phytotherapy, I noticed something interesting. Unlike chamomile, where the conversation often revolves around relaxation and digestion, or rosemary, which leads quickly into cognition and antioxidants, calendula's chemistry seems remarkably focused.

Many of the compounds in calendula point toward a common theme: protecting and repairing tissues.

Once I understood that, calendula stopped feeling like a random skin herb and started making a lot more sense.

Calendula Is a Flower Built for Protection

Calendula (Calendula officinalis) belongs to the Asteraceae family, also known as the daisy family.

Its relatives include:

• Chamomile

• Yarrow

• Echinacea

• Dandelion

• Arnica

One thing you'll notice when studying the daisy family is that many members have strong associations with inflammation, wound care, and tissue support.

Part of that comes from shared chemistry.

Calendula contains several groups of compounds that herbalists and researchers find particularly interesting, including:

• Triterpenoids

• Carotenoids

• Flavonoids

• Polysaccharides

• Sesquiterpene glycosides

Each group contributes something slightly different, but together they help explain why calendula developed such a strong reputation as a healing herb.

The Triterpenoids: Calendula's Heavy Lifters

If chamomile has apigenin and rosemary has rosmarinic acid, calendula's stars are probably its triterpenoids.

These compounds don't get nearly as much attention in popular herbal writing, which is a shame because they're fascinating.

Triterpenoids are large, complex molecules that plants produce for protection and structural support. In calendula, researchers have identified several triterpenoid compounds, including faradiol and its esters.

Faradiol is one of the compounds most often associated with calendula's anti-inflammatory activity.

When tissues are damaged, the body releases chemical messengers that trigger inflammation. This process is necessary because inflammation helps initiate repair. However, excessive inflammation can also increase redness, swelling, discomfort, and tissue irritation.

Research suggests that calendula's triterpenoids may help regulate some of these inflammatory pathways.

This doesn't mean calendula shuts inflammation off. Inflammation is part of healing and we don't want to eliminate it completely.

Instead, calendula appears to help create conditions that support healthy tissue repair without excessive irritation.

The more I read about calendula, the more I noticed that many of its traditional uses revolve around exactly this idea.

Cuts.

Scrapes.

Minor burns.

Rashes.

Chapped skin.

In all of these situations, the body is trying to repair itself. Calendula appears to support that process.

The Bright Orange Pigments Are Doing More Than Looking Pretty

One of the easiest things to notice about calendula is its color.

Those bright orange and yellow petals aren't just decorative.

They're packed with compounds called carotenoids.

Carotenoids are pigments that plants use to capture light and protect themselves from oxidative damage. They are also responsible for the colors found in carrots, pumpkins, sweet potatoes, and many other brightly colored plants.

Some of the major carotenoids found in calendula include:

• Lutein

• Zeaxanthin

• Lycopene

• Beta-carotene

These compounds function as antioxidants.

To understand why that's important, imagine leaving a piece of metal outside in the rain.

Over time it begins to rust.

Oxidation causes damage.

Something similar happens within living organisms. Normal metabolism produces reactive molecules that can damage cells if they aren't kept under control.

Plants need protection from this damage.

So do humans.

The carotenoids in calendula help explain why the flower is often associated with protecting and supporting healthy tissues.

When herbalists talk about calendula helping damaged skin, antioxidants are likely part of that story.

Flavonoids: The Compounds That Keep Showing Up

At this point I've studied enough herbs to realize that flavonoids seem to appear almost everywhere.

Calendula is no exception.

Like many medicinal plants, calendula contains a variety of flavonoids that contribute antioxidant and anti-inflammatory activity.

Plants produce flavonoids for protection against environmental stressors such as ultraviolet radiation, pathogens, and oxidative damage.

When humans consume plants containing flavonoids, some of those protective properties may benefit us as well.

This is one reason you'll often see overlap between traditional herbal uses and modern research.

Herbalists didn't know what flavonoids were.

They simply observed results.

Now we're beginning to understand some of the chemistry that may help explain those observations.

Why Calendula Is Called a Vulnerary

One of the words that kept appearing while I researched calendula was "vulnerary."

It's an old herbal term that simply means a substance that supports wound healing and tissue repair.

Calendula is often considered one of the classic vulnerary herbs.

The more I learned, the more I understood why.

Unlike some herbs that seem to focus heavily on one body system, calendula appears to have a remarkable affinity for damaged or irritated tissues.

This is likely due to multiple compound groups working together.

The triterpenoids appear to help regulate inflammation.

The carotenoids provide antioxidant support.

The flavonoids contribute additional protection.

Polysaccharides may support immune activity and tissue recovery.

No single compound explains calendula's reputation.

The herb works because many compounds are contributing to the same overall goal.

The Surprising Role of Polysaccharides

When people think about medicinal plants, they usually focus on aromatic compounds or antioxidants.

Polysaccharides don't get nearly as much attention.

Polysaccharides are long chains of sugar molecules that plants use for structure, storage, and communication.

Researchers have found that some plant polysaccharides appear to influence immune activity.

Calendula contains several polysaccharides that researchers believe may contribute to its traditional use in supporting healthy tissue recovery.

This is one of those areas where science is still catching up.

We know the compounds are there.

We know they appear biologically active.

We're still learning exactly how they fit into the larger picture.

Why Calendula Is Usually Used Externally

One thing I noticed while studying calendula is that many herbalists think of it primarily as a topical herb.

That's unusual.

Chamomile is often consumed as a tea.

Lemon balm is commonly taken internally.

Rosemary is both culinary and medicinal.

Calendula, however, is most famous for oils, salves, creams, compresses, and washes.

The chemistry helps explain why.

Many of calendula's most studied compounds seem particularly relevant to tissue repair and inflammation regulation.

That's exactly what you're looking for when dealing with irritated skin.

Of course, calendula can also be used internally, but its reputation was largely built through direct contact with damaged tissues.

When you understand the chemistry, that historical use suddenly seems very logical.

Why Herbalists Use the Whole Flower

The more I study medicinal plants, the more I realize how tempting it is to search for the one compound responsible for everything.

Calendula resists that temptation.

Faradiol helps explain some of its anti-inflammatory activity.

Carotenoids contribute antioxidant support.

Flavonoids add another layer.

Polysaccharides contribute yet another.

The flower's traditional reputation wasn't built by a single constituent.

It was built by all of them working together.

This is one reason herbalists often talk about synergy. The compounds in a plant evolved together, and many appear to complement one another.

The overall activity of calendula is greater than any single compound can fully explain.

When I look at calendula growing in the garden now, I still appreciate the bright flowers.

But I also see something else.

I see a plant that has spent millions of years developing chemistry designed to protect and repair living tissues. It just so happens that some of that chemistry appears useful to us as well.

And honestly, I think that's a lot more interesting than simply calling calendula a skin herb.