IngredientsThe term Sequoia, as used in the dietary supplement and natural ingredient context, most commonly refers to one or both of two closely related coniferous trees: Sequoia sempervirens (D. Don) Endl. — the coast redwood or California redwood — and Sequoiadendron giganteum (Lindl.) J. Buchholz — the giant sequoia or Sierra redwood. A third closely related species, Metasequoia glyptostroboides (the dawn redwood), is occasionally grouped with them phylogenetically but is rarely used in supplement applications. Both primary species belong to the family Cupressaceae and the order Pinales.
Sequoia sempervirens (coast redwood) and Sequoiadendron giganteum (giant sequoia) are two redwood species on the west coast of the United States; they are among the most widely recognized and iconic tree species on earth because of their height and volume, and they are also listed as endangered species on the IUCN Red List. S. giganteum thrives in fragmented groves in the U.S. Sierra Nevada mountain range, and S. sempervirens is naturally distributed along the Pacific Coast from southwest Oregon to central California.
S. giganteum and its close relative Metasequoia are diploids (2n = 2x = 22), whereas S. sempervirens is a natural hexaploid (2n = 6x = 66), which is quite rare among gymnosperms. This unusual polyploidy in S. sempervirens is considered notable in the evolutionary biology of conifers.
The giant sequoia is a majestic tree native to California, reaching 80 meters in height and 10 meters in circumference. Its evergreen leaves are flat, pointed, aromatic needles whose scent is reminiscent of anise. It is a conifer that can exceed one thousand years of life.
Sequoia is encountered in several commercially available forms:
The Yurok, Karuk, and Chilula tribes, among other Native American groups, showed profound respect for these towering trees and integrated them into their religious practices and everyday existence.
Native American tribes such as the Yurok and Karuk utilized redwood bark in poultices to treat wounds, burns, and skin irritations, capitalizing on its soothing and potentially antiseptic qualities. California Redwood (Sequoia sempervirens) has a storied history among the indigenous peoples of the Pacific Coast, particularly in Northern California, where traditionally various parts of the redwood tree — including the bark, needles, and sap — were valued for their medicinal properties.
Native people commonly prepared the Sequoia sempervirens bark into medicinal teas and applied it in poultices to combat colds, fevers, and infections. The natural antibacterial properties of the tannins found in the bark made it suitable for treating wounds. Indigenous tribes practiced making water infusions from the needles because they believed it strengthened respiratory systems and enhanced immune defenses.
The aromatic resins served dual purposes by treating joint pain and by being used as incense in purification rituals.
The aromatic needles were sometimes used in steam inhalations for respiratory complaints, capitalizing on their invigorating scent and potential expectorant qualities.
Gemmotherapy is the branch of phytotherapy that uses fresh plant parts in the embryonic state (such as buds or young shoots) whose active ingredients are extracted by an appropriate solvent; it is, as a remedy for human health, among the first discovered natural therapies used by men as well as primates.
Experimentally, it has been found that many active ingredients, contained in considerable quantities in the buds, are often found only in traces in the adult parts of the plants. This rationale underlies the specific use of young sequoia shoots rather than mature wood or bark in gemmotherapy preparations.
Pol Henry, often considered the father of gemmotherapy, described sequoia buds as having revitalizing and tonic properties, particularly beneficial for elderly people. His early 20th-century work was subsequently elaborated upon by Dr. Max Tétau, whose writings on Sequoiadendron giganteum as a "polychrest" of gemmotherapy have become reference texts in this tradition.
In gemmotherapy, sequoia buds are prized for their toning action, particularly in mature men. They are reputed to improve prostate health, addressing chronic prostatitis and prostate adenoma. The buds are also used for their purported ability to stimulate adrenal hormones, which is said to support sexual functions.
In women, sequoia is used in gemmotherapy to help fight fibroids and to combat osteoporosis through its purported ability to stimulate bone formation. More generally, sequoia is promoted as an anti-aging remedy for men and, to a lesser extent, for women.
The immunomodulatory and antiulcerogenic activities of the chloroform, ethyl acetate, and n-butanol fractions of Sequoia sempervirens leaves have been investigated. The ethyl acetate fraction showed the best results, with a high significant increase of RAW 264.7 macrophage cells and reduction of ulcer number and severity compared with ranitidine. HPLC was used to investigate phenolic contents, identifying 12 phenolic acids and 15 flavonoids (in mg/g dry powder ± SD); protocatechuic acid was the predominant phenolic acid (10.94 ± 1.22), followed by salicylic acid (4.52 ± 1.23), coumaric acid (4.42 ± 0.21), and sinapic acid (3.57 ± 0.63).
Vitexin showed the highest content of identified flavonoids (6.67 ± 1.21), followed by orientin (5.96 ± 1.18) and quercetin-3,7-di-O-glucoside (4.92 ± 0.73). Ten flavonoids — including isoorientin, isovitexin, orientin, vicenin-II, mangiferin, vitexin, luteolin, apigenin, and kaempferol — were isolated from S. sempervirens leaves.
Young sequoia shoots contain flavonoids including rutin and quercitrin, as well as phenolic compounds; in the wood portion there are cyclitols: sequoitol, myoinositol, and pinitol.
The bark is rich in tannins, which, based on their known chemistry, underlie its astringent and antimicrobial properties. Condensed tannins (proanthocyanidins) are characteristically abundant in the bark of coniferous species and are responsible for the distinctive reddish coloring of redwood bark.
Secondary metabolites — polyphenols, catechins, and terpenoids — are mainly localized in the epidermal, parenchymal, and conductive tissues of Sequoia leaves and stems.
Shikimic acid has been identified as a major component of Sequoiadendron giganteum (SG) callus extract. Shikimic acid (3,4,5-trihydroxy-1-cyclohexene-1-carboxylic acid) is a well-characterized metabolic intermediate in the biosynthesis of aromatic amino acids; it is notably the precursor from which the antiviral drug oseltamivir (Tamiflu) is semi-synthetically derived. Its presence as a major constituent in giant sequoia callus tissue is the basis for significant recent dermatological research (see Section 5).
The wood fraction of sequoia contains cyclitols including sequoitol, myoinositol, and pinitol. Young sequoia shoots used in gemmotherapy preparations contain both flavonoids (rutin, quercitrin) and phenolic compounds, while the wood part contains cyclitols: sequoitol, myoinositol, and pinitol. Pinitol and myoinositol have been studied in other botanical contexts for effects on insulin signaling and bone metabolism, though specific clinical evidence from sequoia-derived cyclitols is lacking.
The high level of magnesium found in the plant is proposed to produce a tonic effect, and the zinc content is noted to potentially sustain prostate function, according to gemmotherapy practitioners. These claims are based on gemmotherapy literature and have not been independently validated in clinical trials.
The most mechanistically detailed peer-reviewed evidence concerning a sequoia-derived compound relates to shikimic acid from Sequoiadendron giganteum. Shikimic acid, a major component of Sequoiadendron giganteum callus extract, was demonstrated to induce mesenchymal-to-epithelial transition (MET) and consequently convert human dermal fibroblasts to neural precursor-like skin precursor cells (NeuSKPCs).
The reprogrammed cells expressed nestin (a neural precursor-specific protein), fibronectin, and vimentin, and could differentiate into the ectodermal and mesodermal lineage. Nestin expression was induced by shikimic acid through the mannose receptor and subsequent MYD88 activation, leading to P38 phosphorylation and then CREB binding to the nestin gene promoter.
Results of an artificial skin model and a clinical study on aged female volunteers show that shikimic acid improves skin regeneration. This represents one of the very few published studies involving human tissue or volunteers, though it was conducted in an artificial skin model context and in a small volunteer cohort (see Section 5).
Sequoia extractive substances obtained from intact and callus tissues demonstrate high biological (fungicidal) activity and cytotoxicity. An inhibitory effect on Fusarium oxysporum was noted when 200 mg/L of Sequoia extract was added to the nutrient medium.
Extracts of redwood callus cultures were low in toxicity to normal FetMSC cells but inhibited the growth of lines of "immortal" cervical HeLa cancer cells and human glioblastoma A172. This observation from an in vitro cell-culture study (2024, published in the journal Life) is preliminary and does not constitute evidence of anticancer efficacy in humans.
The immunomodulatory and antiulcerogenic activities of the chloroform, ethyl acetate, and n-butanol fractions of Sequoia sempervirens leaves were investigated. The ethyl acetate fraction showed the best results regarding a high significant increase of RAW 264.7 macrophage cells and reduction of ulcer number and severity compared with ranitidine. This was an in vitro and preclinical (cell and animal model) study only.
Phytochemical analyses have revealed that sequoia extracts contain a range of potentially beneficial constituents, such as polyphenols, flavonoids, and lignans, which are known for their antioxidant properties in other plant sources. A limited number of in vitro studies have suggested these compounds may help counteract oxidative stress, one of the underlying factors in various chronic conditions.
Evidence level: Preliminary — in vitro, ex vivo artificial skin model, and a small clinical component.
A study published in Stem Cell Research & Therapy (2021, PMC8196440) hypothesized that a component of plant stem cells could convert human fibroblasts to skin-derived precursors (SKPs). Human dermal fibroblasts were treated with shikimic acid, a major component of Sequoiadendron giganteum callus extract. The characteristics of these reprogrammed cells were analyzed by qPCR, western blot, colony-forming assay, and immunofluorescence staining. Artificial human skin was used for CO₂ laser-induced wound experiments, and human tissues were analyzed by immunohistochemistry.
The team of researchers from Seoul National University Hospital, SK Chemical, AmorePacific, Chung-Ang University College of Medicine, and Pusan National University School of Medicine hypothesized that a component from plant stem cells could convert human fibroblasts to skin-derived precursors (SKPs).
The authors confirmed that shikimic acid facilitated the healing of cut injury and enhanced dermal reconstruction in a human artificial skin model. In vivo, it also increased the expression of stem cell markers in the basal layer of the epidermis and collagen deposition in the dermis.
Limitations: The wound healing component used an artificial ex vivo skin model, not a controlled clinical trial. The clinical component involved aged female volunteers but appears to have been small and is not described as a randomized controlled trial in available abstracts. The industrial affiliations of some authors (SK Chemical, AmorePacific) indicate a potential commercial interest in the findings. No independent replication of these findings has been identified in the literature as of this writing.
Evidence level: Preclinical (in vitro) only.
Intact tissues of Sequoia plants and cell cultures initiated from them in vitro are producers of secondary metabolites with high biological activity. Studies on coast redwood (Sequoia sempervirens) have focused on in vitro plant cell cultures and phytotoxicity and cytotoxicity of extracts.
The inhibitory effect on Fusarium oxysporum was noted when 200 mg/L of Sequoia extract was added to the nutrient medium. This work is relevant to potential agricultural applications and to understanding the plant's phytochemical defense systems, but its translatability to human antifungal or antimicrobial therapy has not been studied.
Evidence level: Preclinical (in vitro and cell-based) only.
The ethyl acetate fraction of S. sempervirens leaves showed high significant increase of RAW 264.7 macrophage cells and reduction of ulcer number and severity compared with ranitidine in preclinical in vitro assays. These results, published by researchers from the National Organization for Drug Control and Research in Egypt, represent the first detailed report on phenolic content and bioactivity of S. sempervirens leaves grown in Egypt. No human clinical trials have followed from these preliminary findings.
Evidence level: Preliminary in vitro only.
Extracts of redwood callus cultures were low in toxicity to normal FetMSC cells but inhibited the growth of lines of "immortal" cervical HeLa cancer cells and human glioblastoma A172. This 2024 paper published in Life (MDPI, DOI: 10.3390/life14121694) characterizes these findings as preliminary and as providing a basis for further investigation of Sequoia as a source of cytotoxic secondary metabolites. No animal or human studies have followed, and these cell-line results cannot be extrapolated to clinical anticancer efficacy.
Evidence level: Traditional gemmotherapy claims only; no peer-reviewed controlled clinical trials identified.
Giant sequoia bud extract seems to represent a therapeutic approach in the initial stages of benign prostatic hypertrophy (BPH — first and second stage), because, while not reducing hypertrophy, it is reported to be effective on the symptom complex. This bud extract is also described as a remedy for prostatitis, not so much acute as chronic, and is considered a remedy for the senescent and adenomatous prostate. These claims derive from gemmotherapy literature, not from peer-reviewed controlled clinical trials.
As noted on U.S. DailyMed labeling for sequoia gigantea gemmotherapy products, this homeopathic product has not been evaluated by the FDA for safety or efficacy, and the FDA is not aware of scientific evidence to support homeopathy as effective.
Evidence level: Traditional gemmotherapy claims only; no peer-reviewed controlled clinical trials identified.
Sequoia buds are reputed in the gemmotherapy tradition for their ability to combat tissue sclerosis, such as osteoporosis, by stimulating bone formation.
Sequoia, associated with cranberry bud extract (Vaccinium vitis idaea) and rosemary bud extract, is described in gemmotherapy literature as seeming to effectively counteract senile osteoporosis. Giant sequoia bud extract is also indicated in the "glass bones" disease where it reportedly reduces the number of spontaneous fractures, according to Tétau M., Nouvelles cliniques de gemmothérapie, Éditions Similia, France, 1991. These references are to gemmotherapy monographs, not to peer-reviewed controlled clinical trials.
Evidence level: Traditional gemmotherapy claims only; no peer-reviewed controlled clinical trials identified.
Pol Henry described sequoia buds as having revitalizing and tonic properties, particularly beneficial for elderly people. According to his research, sequoia buds stimulate the adrenal glands, which helps strengthen the endocrine system.
In gemmotherapy texts, giant redwood's primary action is described as a tonic for the adrenal gland, stimulating cortisol production, resolving inflammation, and associated pain. Its secondary effect is described as acting on the endocrine system, affecting prostate and testicular health and harmonizing the production of estrogen and testosterone. None of these proposed mechanisms have been evaluated in peer-reviewed controlled clinical studies.
Evidence level: Preclinical data from one academic thesis cited in gemmotherapy literature; no peer-reviewed clinical trials identified.
An academic study referenced in gemmotherapy sources (Ermini F., Degree Thesis, University of Siena, Faculty of Pharmacy, 1995–1996) is cited as indicating that sequoia bud extract demonstrates anti-inflammatory activity that can indirectly contribute to the improvement of sexual abstinence in the elderly. There is also an indication that giant sequoia rebalances spermatogenesis. These claims are based on unpublished thesis work cited in gemmotherapy literature, not in peer-reviewed journals.
Robust clinical trials specifically investigating sequoia's effects in human populations are currently lacking. Scientific inquiry into its nutritional and health benefits is still emerging. The vast majority of health claims attributed to sequoia in current supplement and gemmotherapy contexts are based on traditional use records, practitioner-authored gemmotherapy monographs, and small preclinical (in vitro or cell model) studies. The one published study with a clinical component (Kwon et al., 2021, Stem Cell Research & Therapy) specifically involved shikimic acid from Sequoiadendron giganteum callus in the context of dermatology.
No standardized pharmacopeial dosage has been established for any sequoia preparation by a recognized regulatory body such as the European Medicines Agency (EMA), the European Food Safety Authority (EFSA), or the U.S. NIH Office of Dietary Supplements. Dosages cited below are those reported in supplement labeling and gemmotherapy practitioner literature, reproduced strictly as documented in identified sources.
No peer-reviewed clinical dose-finding or dose-ranging studies for sequoia preparations have been identified.
Gemmotherapy and homeopathic products containing Sequoiadendron giganteum listed on U.S. DailyMed have not been evaluated by the FDA for safety or efficacy, and the FDA is not aware of scientific evidence to support homeopathy as effective. These products are marketed under the FDA's regulatory framework for homeopathic products, which does not require pre-market demonstration of safety or efficacy.
Although natural and well-tolerated in general use, redwood preparations should be used with caution in certain cases, and they are not recommended for pregnant and breastfeeding women due to their hormonal effects. Commercial gemmotherapy products labeled with sequoia warn: "Do not use if you are pregnant or breastfeeding unless directed by a healthcare practitioner."
Use should be avoided in cases of hormone-dependent disorders, especially those prone to hormonal cancers. This caution stems from the purported hormonal (estrogenic/androgenic) activity attributed to sequoia in gemmotherapy literature. No pharmacological evidence from controlled studies quantifying this estrogenic or androgenic activity has been identified.
Commercial gemmotherapy preparations of Sequoia gigantea contain 36.6% alcohol (V/V), which is a relevant consideration for individuals who avoid or are sensitive to alcohol, as well as for children. Products must be evaluated individually for their alcohol concentration prior to use.
The EWG Skin Deep database rates Sequoia Sempervirens Leaf Cell Extract as LOW concern for cancer, LOW for allergies and immunotoxicity, and LOW for developmental and reproductive toxicity. This rating reflects cosmetic/topical ingredient use and is not a clinical safety assessment.
No formal pharmacovigilance data, adverse event reports, or drug interaction studies specific to sequoia preparations have been identified in peer-reviewed sources or regulatory databases. The absence of safety data should not be construed as evidence of safety; it reflects the very limited clinical research conducted on this ingredient.
Because multiple species — Sequoia sempervirens, Sequoiadendron giganteum, and occasionally Metasequoia glyptostroboides — are sold under overlapping common names ("redwood," "sequoia," "giant sequoia"), and because their phytochemical profiles may differ meaningfully, purchasers of sequoia-derived supplements should verify the precise botanical identity of the source material, including the plant part used (buds, bark, needles, or wood) and whether the material was obtained from cultivated or wild-crafted sources. Products labeled only as "sequoia" without further specification cannot reliably be assessed for phytochemical content or activity.
Health conditions that Sequoia may help support.
Body systems that Sequoia may help support.
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