Frankincense & Myrrh: The Sacred Resins That Built Empires

In 2004, a team of French chemists led by C. Mathe and G. Culioli published a study in the Journal of Chromatography A. They had run gas chromatography-mass spectrometry on the residue inside an ointment vessel from a tomb at Dahshour, Egypt, excavated over a century earlier by Jacques de Morgan. The vessel came from the burial of Princess Sat-mer-Hout, sister of Pharaoh Amenemhat I, dating to the XIIth Dynasty (c. 1897-1844 BCE). The residue contained alpha-boswellic acid, beta-boswellic acid, and their O-acetyl derivatives. It was frankincense, nearly four thousand years old, and still chemically identifiable.

That finding confirmed what textual sources had long suggested: the resins of Boswellia and Commiphora trees were among the most valued substances in the ancient world. Their trade financed entire kingdoms. Their smoke filled every major temple from Memphis to Rome. Their chemistry, as it turns out, interacts with the brain’s inflammation, pain, and mood pathways in ways that modern pharmacology is only beginning to map.

The Trees That Weep

Frankincense comes from several species of Boswellia, small, gnarled, drought-adapted trees that grow in some of the harshest landscapes on earth: the limestone escarpments of Dhofar in Oman, the arid hills of Somaliland and Ethiopia, the dry forests of India. When the bark is cut, the tree bleeds a milky sap that hardens into amber-golden “tears” with a scent that is immediately recognizable: citrus and pine, warm and resinous.

Myrrh comes from Commiphora species, an even larger genus of thorny shrubs and small trees growing across the Horn of Africa and the Arabian Peninsula. Its resin is darker, reddish-brown, with a bitter-sweet aroma that has depth and earthiness where frankincense has brightness.

The most prized frankincense comes from Boswellia sacra (Oman and Yemen), also classified as B. carterii in Somalia, though whether these are the same species remains contested. Woolley et al. (2012) found dramatically different alpha-pinene enantiomeric ratios between Omani and Somali resins, suggesting distinct species despite being treated as synonyms by most databases. B. serrata from India produces a spicier, woodier resin used in Ayurvedic medicine as salai guggul. B. frereana, called “Maydi” or “King of Frankincense” in Somalia, produces a honeyed, delicate resin traditionally chewed as gum. B. papyrifera in Ethiopia produces copious but less complex resin.

For myrrh, Commiphora myrrha is the classic species of historical record: deep, bitter-sweet, wine-dark tears. C. guidottii produces the softer “opoponax” or sweet myrrh prized in perfumery.

Harvesting follows a method essentially unchanged since antiquity. Harvesters make shallow incisions in the bark during the dry season, a practice called tapping. The tree responds by bleeding sap to seal the wound. Two to three weeks later, the hardened tears are collected. A single tree may be tapped multiple times per season. In Somalia, there are two tapping periods per year, each three to four months long, with successive tappings at roughly fifteen-day intervals.

The quality hierarchy is traditional and specific. In Oman, the grading system ranks Hojari (the green-tinged tears from high-altitude inland trees) as the finest, followed by Nejdi, Shazri, and Sha’abi. Quality correlates with color (whiter or greener is better), altitude, and tapping order. First tappings produce the cleanest resin.

The Road That Built Kingdoms

By the first millennium BCE, an overland trade network rivaling the Silk Road in economic importance ran from the frankincense groves of southern Arabia to the ports of the Mediterranean. Pliny the Elder, writing in the first century CE, described the route in detail in Book 12 of his Natural History. The journey from Thomna (capital of the Gebbanitae) to Gaza on the Mediterranean coast covered 65 stages with halts for camels, approximately 2,437 Roman miles. The trip took about twelve weeks.

Pliny also recorded the costs. By the time a camel-load of frankincense reached the Mediterranean, expenses had mounted to 688 denarii per camel, including taxes, water, fodder, lodging, and tolls paid to priests, the king’s secretaries, guards, gatekeepers, and servants at every stop along the route. Diverting from the established road was a criminal offense.

The key stops tell the story of an entire civilization organized around aromatic resin. Dhofar and the Hadramaut valley provided the raw material. Qana served as a shipping port. Shabwa, the capital of the Kingdom of Hadramaut from the first millennium BCE to the fifth century CE, was the major caravan junction. (Pliny called it Sabota and described a prosperous city with multi-story fortifications.) From there, the route ran north through Najran, Dadan, and Hegra to Petra, the Nabataean capital carved into rose-red sandstone that still draws visitors today. The Nabataeans built their entire civilization on incense commerce, charging as much as 25 percent on top of goods they handled as middlemen. From Petra, the resins went to Gaza, and from Gaza to Egypt, Greece, and Rome.

The economic scale was staggering. Pliny estimated in Book 12, Section 84 that Rome spent 100 million sestertii annually on Arabian and Indian aromatics. By the first century CE, Roman annual consumption has been estimated at roughly 2,800 tons of frankincense and 550 tons of myrrh, though these figures are difficult to verify precisely. When Nero’s wife Poppaea died in 65 CE, Pliny wrote that the emperor burned more frankincense at her funeral than Arabia produced in an entire year. (He gave no specific weight. The claim is rhetorical, designed to illustrate Roman excess, not to provide a quantitative measure.)

The decline was gradual and multi-causal. Augustus developed Red Sea ports and exploited monsoon wind patterns to enable direct maritime trade with India, bypassing the overland route and Nabataean middlemen. Rome’s annexation of the Nabataean kingdom in 106 CE diminished Petra’s role as an independent hub. Christianity initially reduced demand for incense (early Christians frowned on pagan cremation and sacrificial practices that relied heavily on aromatics), though the church eventually reintroduced incense into its own liturgy. By the third century CE, Shabwa was destroyed. The specialized caravan system never recovered its former scale.

What They Meant to the Ancient World

The significance of these resins was not merely economic. They occupied a central position in the religious and medical practices of virtually every civilization that encountered them.

In Egypt, temples divided the day into three incense offerings: frankincense in the morning, myrrh at midday, and Kyphi (a complex compound of up to sixteen ingredients including both resins) in the evening. The Ebers Papyrus (c. 1500 BCE) lists both substances for medicinal use. Queen Hatshepsut sent a full naval expedition to the Land of Punt around 1472 BCE specifically to bring back live incense trees for transplantation. The reliefs at Deir el-Bahri, on the second terrace of her mortuary temple, depict five ships carrying approximately 210 men and 31 live trees, each requiring four to six men to carry on poles. The trees were planted within the temple precinct as “plants for the god.”

However, what the Egyptians actually meant by their resin terminology is more complicated than previously assumed. A landmark 2023 study published in Nature by Rageot, Stockhammer, and colleagues analyzed 31 ceramic vessels from a 26th Dynasty (664-525 BCE) embalming workshop at Saqqara. Many vessels bore hieratic labels identifying their contents. The results overturned longstanding assumptions: antyw, traditionally translated as myrrh, turned out to be a mixture of cedar oil, juniper or cypress oil, and animal fats. snTr, long assumed to mean frankincense, may be primarily Pistacia (pistachio/mastic resin). Chemical analysis of mummies does detect Commiphora and Boswellia compounds, but the relationship between Egyptian substance names and specific botanical resins is now understood to be far more complex than a simple one-to-one mapping.

In Jewish tradition, frankincense (levonah, from a Hebrew root meaning “white”) was a required component of the sacred ketoret incense burned in the Temple. The recipe is specified in Exodus 30:34-38 with four named ingredients: nataf, shechelet, chelbenah, and levonah. The Talmud (Keritot 6a) expands the recipe to eleven ingredients with specific weights, adding myrrh (mor), cassia, spikenard, saffron, costus, aromatic bark, and cinnamon.

In Matthew 2:11, the gifts of the Magi to the infant Jesus are gold (chrysos), frankincense (libanos), and myrrh (smyrna). The traditional reading assigns each gift a symbolic meaning: kingship, divinity, and mortality. Myrrh appears again at the end of the narrative. In John 19:39-40, Nicodemus brings approximately 100 Roman pounds of myrrh and aloes for Jesus’s burial. The city of Smyrna (Revelation 2:8) takes its name from the Greek word for myrrh.

In Rome, no sacrifice was complete without frankincense thrown onto the altar fire. The practical purpose was masking the odor of animal sacrifice; the spiritual purpose was honoring the deity. In the imperial cult, burning frankincense before imperial images expressed civic loyalty. Refusing to do so could mark someone as a Christian. Herodotus, writing around 430 BCE, had described frankincense trees as guarded by “winged serpents of small size and various colours,” a traveler’s tale designed to inflate mystery and price. Theophrastus, a century later, corrected this with a more sober account drawn from reconnaissance ships sent by Alexander the Great: the inhabitants, he noted, were “righteous people” who had not bothered to guard their trees.

Dioscorides, writing his De Materia Medica around 50-70 CE, described frankincense as “warm” and “astringent,” useful for sealing wounds and treating asthma. Myrrh he called “warming, sleep-inducing, and astringent,” prescribing it diluted in wine as a mouthwash. That specific use, myrrh for oral health, has held up under modern clinical scrutiny.

The Chemistry Nobody Expected

The most significant scientific development in frankincense research is the identification and characterization of boswellic acids. These triterpene compounds were first isolated from Boswellia resin by Winterstein and Stein in 1932, but their biological mechanism was not understood for another sixty years.

In 1992, Safayhi and Ammon at the University of Tuebingen demonstrated that AKBA (acetyl-11-keto-β-boswellic acid) is a potent inhibitor of 5-lipoxygenase (5-LOX), a key enzyme in the biosynthesis of leukotrienes, which are among the body’s primary inflammatory mediators. The inhibition is non-competitive and non-redox, meaning AKBA works through a fundamentally different mechanism than standard anti-inflammatory drugs like aspirin or ibuprofen. In 2020, Gilbert et al. published the crystal structure in Nature Chemical Biology, showing that AKBA binds to an allosteric site approximately 30 angstroms from the catalytic iron center.

This matters because 5-LOX inhibition addresses a pathway that conventional NSAIDs do not. Products based on standardized Boswellia extracts (5-Loxin, containing 30% AKBA, and Aflapin, containing 20% AKBA) are now marketed for osteoarthritis and have supporting randomized controlled trials. The major limitation is bioavailability: over 95% of boswellic acids bind to plasma proteins, and they undergo extensive CYP3A4 metabolism.

Myrrh’s pharmacology follows a different but equally interesting path. In 1996, Dolara et al. published a short paper in Nature demonstrating that furanoeudesma-1,3-diene, a sesquiterpene isolated from myrrh, has analgesic effects that are reversed by naloxone. Naloxone is the standard opioid receptor antagonist. Its reversal of myrrh’s painkilling effect means the compound acts, at least partly, through opioid receptors. This is a plausible pharmacological basis for myrrh’s millennia-old use in pain relief and wound treatment.

Then there is incensole acetate. In 2008, Moussaieff et al. published a study in the FASEB Journal showing that this diterpene from frankincense activates TRPV3, a transient receptor potential channel expressed in the brain. In mice, it produced anxiolytic and antidepressant effects. The effects were abolished in TRPV3 knockout mice, confirming the receptor mechanism. The effective concentration was 16 micromolar. No human clinical trial has been conducted. Whether sufficient compound reaches the brain through inhalation of frankincense smoke remains undemonstrated. But the finding provides a molecular framework for understanding why burning frankincense in temples might have had a calming effect on congregations, beyond the purely psychological.

The German government granted EU orphan drug designation (EU/3/02/117) for a Boswellia serrata extract for the treatment of peritumoral brain edema in 2002. A 2011 randomized controlled trial by Kirste et al. (44 patients) found that 60% of patients receiving the Boswellia extract achieved greater than 75% reduction in brain edema, compared to 26% in the placebo group. No Phase III trial for any direct anti-cancer application has been completed.

The Trees Are Dying

In 2019, Bongers et al. published a study in Nature Sustainability that should have received far more attention than it did. They surveyed 23 populations of Boswellia papyrifera across Ethiopia, examining 21,786 individual trees. Their finding: over 75% of populations lacked saplings entirely. Seedlings germinated, but they were not surviving to the sapling stage. Successful regeneration appeared to have ceased since approximately 1955. At current trajectories, they projected a 50% decline in frankincense production within 20 years.

The causes are multiple and compounding. Over-tapping weakens trees: too many incisions, too frequently, reduces resin quality and eventually kills the tree. Livestock grazing (particularly by camels and goats) destroys seedlings before they can establish. Fire clears understory and kills young trees. Land conversion for agriculture eliminates habitat. Climate change is shifting rainfall patterns in already marginal environments.

Not all species are equally affected. A 2025 rapid conservation assessment of Boswellia sacra in Oman (Johnson et al., Journal of Arid Environments) found the species covering at least 3,465 square kilometers, with 97% of transects showing evidence of regeneration. Oman’s frankincense may be holding on. But B. papyrifera in Ethiopia is recommended for IUCN Vulnerable status, and B. ogadensis is considered Critically Endangered.

The economic realities for harvesters are stark. In Somalia, approximately 10,000 families depend primarily on incense gathering. A good tree yields 300-500 grams of myrrh resin per year. The price at harvest sites runs about one US dollar per kilogram. Retail prices are roughly five times that. In southern Ethiopia, the annual cash income from frankincense averages 60 US dollars per adult, representing 35% of total household cash income. Frankincense is Somalia’s third-largest income source after livestock and agriculture.

The conservation challenge is that restricting harvesting to protect trees directly threatens livelihoods that already exist at subsistence level. CITES discussions are ongoing, but some experts argue that trade restrictions could do more harm than good for communities that depend on the resin trade.

What Smoke Actually Does

When resin burns, it does not simply evaporate. It undergoes pyrolysis, thermal decomposition that creates new compounds not present in the raw resin. The smoke composition is different from the resin itself, which may explain why burned incense has different effects than essential oils or extracts.

This also means incense smoke is not chemically benign. Studies have measured particulate matter in incense smoke at over 45 milligrams per gram of material burned, compared to approximately 10 milligrams per gram for cigarette smoke. The smoke also contains trace amounts of benzene, toluene, polycyclic aromatic hydrocarbons (PAHs), and formaldehyde.

The largest epidemiological study on the subject, conducted by Friborg et al. (2008) as part of the Singapore Chinese Health Study, followed 61,320 participants. Long-term, heavy incense use was associated with an increased risk of upper respiratory tract squamous cell carcinoma. It was not, notably, associated with lung cancer overall. The distinction matters: the particulates from incense tend to be deposited in the upper airways rather than penetrating deep into the lungs the way cigarette smoke does.

For occasional use in well-ventilated spaces, the risk is considerably lower. Electric incense warmers, which heat resin below combustion temperature, release aromatic compounds without producing pyrolysis products. They eliminate the smoke issue entirely while preserving much of the olfactory experience.

How to Use Them

Traditional use always involved heat. The most straightforward method remains burning resin on charcoal: place a self-lighting charcoal disc on a bed of sand in a heat-safe censer, let it fully ignite (one to two minutes), then add a small pinch of resin when the charcoal is glowing and covered with gray ash. Less is more. A few tears produce ample smoke. A blend of frankincense and myrrh at roughly two-to-one by weight is the classic combination.

For essential oils, always dilute for skin application (1-3% in carrier oil) and patch test first. Myrrh oil is traditionally contraindicated during pregnancy due to potential uterine-stimulating effects. Concentrated myrrh products may interact with diabetes medications and blood thinners. Consult a healthcare provider before therapeutic use of either resin in concentrated form.

Two Readings

The skeptical reading is clear. Frankincense and myrrh are plant resins with interesting but modest pharmacological activity. The boswellic acid mechanism is real but limited by poor bioavailability. The incensole acetate finding is a single mouse study with no human replication. The myrrh-opioid connection is an in-vitro observation, not a demonstrated clinical effect. Ancient civilizations valued these resins because they smelled good and because human beings are prone to attributing sacred significance to rare, expensive substances from exotic places. The trade was commerce. The temple use was atmosphere. The medical claims were pre-scientific observation dressed up in religious language.

The other reading notices things that do not reduce so cleanly. Two resins from two different plant families, used together across every major civilization for five thousand years, and modern chemistry finds that one inhibits a key inflammatory enzyme through a mechanism no synthetic drug exploits, while the other activates opioid receptors and a third compound from the first one lights up brain regions involved in emotion regulation. The ancient Egyptians assigned frankincense to the morning (when cortisol and inflammation are highest) and myrrh to midday. Dioscorides prescribed myrrh as a mouthwash, and modern clinical studies confirm antimicrobial efficacy against oral pathogens. The nearly 4,000-year-old residue in Princess Sat-mer-Hout’s vessel is not a general aromatic mixture. It is specifically Boswellia, specifically the compounds that include the 5-LOX inhibitor.

There is also the conservation question, which carries its own uncomfortable weight. Over 75% of Ethiopian Boswellia populations have stopped producing saplings. The trees that sustained five millennia of human ritual, trade, and medicine may not survive the next fifty years. The demand that once built the Nabataean kingdom, financed the Hadramaut, and drained the Roman treasury is now destroying the source. Whether modern science can identify the mechanisms fast enough to justify the protection, or whether the trees will disappear while we are still arguing about bioavailability, is an open question that the research raises but does not resolve.