NIH/PubMed & University Evidence Supplement

NOTE: White Papers For All Items Are Available Upon Request

The FDA requires a disclosure that these products have not been evaluated by the FDA are not designed to treat or cure any ailment, including those listed within our website. We use these herbs and oils in concert with our study to provide the most effective calming and soothing results for a host of skin ailments. This does not diminish that the herbs and oils we use individually have significant compounds. This is an outline of herbs and oils in our products as seen through the lens of the NIH and University studies. We make no claims and rely on these studies, and others, to direct us.

Scope. This supplement adds peer-reviewed studies indexed by the U.S. National Library of Medicine/PubMed and studies or reviews authored by university-affiliated investigators. The purpose is scientific substantiation of ingredient selection, not limitation to cosmetic-claim standards. Evidence concerning an isolated constituent, aqueous/alcoholic extract, essential oil, colloidal preparation, or a different fatty-acid profile is identified as such and should not be treated as proof that an OHO oil infusion or finished formula produces the same clinical effect.

Evidence interpretation used throughout this white paper

·       Human clinical evidence is given the greatest translational weight when the studied preparation and route resemble the OHO ingredient.

·       Systematic reviews and university-authored reviews are used to identify active compounds, plausible mechanisms, safety issues, and the overall strength of the literature.

·       Preclinical and mechanistic studies support biological plausibility but are not represented as clinical proof.

·       Chamomile is treated as the whole botanical. Apigenin, alpha-bisabolol/bisabolol oxides, azulenes/chamazulene and other constituents are discussed as naturally occurring chamomile constituents rather than as isolated ingredients in the formula.\

Chamomile (Matricaria recutita / M. chamomilla)

Chamomile flowers contain flavonoids including apigenin, quercetin, patuletin and luteolin derivatives; volatile fractions can contain alpha-bisabolol, bisabolol oxides and azulenes including chamazulene. The dermatologic literature on apigenin is predominantly preclinical, so OHO uses chamomile as a botanical conditioning ingredient rather than claiming that an oil infusion reproduces isolated-compound pharmacology.

·       Srivastava JK, Shankar E, Gupta S. Chamomile: A herbal medicine of the past with bright future / related chamomile bioactivity literature. Key PubMed review: PMID 16628544; DOI: 10.1002/ptr.1900.

·       Apigenin and its dermatological applications: A comprehensive review. PMID: 35998830. Review conclusion: preclinical dermatologic evidence is substantial, but clinical studies of apigenin itself are lacking.

·       Russell K, Jacob SE. Bisabolol. Dermatitis. 2010;21(1):57-58. PMID: 20137740. University affiliation: University of California San Diego School of Medicine. Included only to document bisabolol as a naturally occurring German-chamomile constituent, not as an OHO isolated ingredient.

Calendula (Calendula officinalis)

Calendula contains triterpenoids, flavonoids and other phytochemicals studied in tissue-repair and inflammatory models. Human evidence is mixed: systematic reviews identify promising signals in some wound settings but emphasize heterogeneity and the need for better trials.

·       Givol O, et al. A systematic review of Calendula officinalis extract for wound healing. Wound Repair Regen. 2019;27(5):548-561. PMID: 31145533; DOI: 10.1111/wrr.12737. University affiliations include Tel Aviv University, University of Tasmania and University of Notre Dame Australia.

·       Leach MJ. Calendula officinalis and Wound Healing: A Systematic Review. Wounds. 2008;20(8):236-243. PMID: 25941793. University affiliation: University of South Australia.

Gotu kola (Centella asiatica)

Centella triterpenes such as asiaticoside, madecassoside, asiatic acid and madecassic acid are studied for collagen synthesis, fibroblast activity, angiogenesis and inflammatory modulation. Clinical and preclinical literature supports continued investigation of topical Centella preparations, while extract standardization remains important.

·       Witkowska K, et al. Topical Application of Centella asiatica in Wound Healing: Recent Insights into Mechanisms and Clinical Efficacy. Pharmaceutics. 2024;16(10):1252. PMID: 39458583; PMCID: PMC11510310; DOI: 10.3390/pharmaceutics16101252. Poznan University of Medical Sciences.

·       A Systematic Review of the Effect of Centella asiatica on Wound Healing. PMID: 35328954. Four clinical trials were included.

Comfrey (Symphytum spp.)

Topical comfrey preparations have human wound-healing literature as well as preclinical tissue-repair data. These studies generally used defined extracts or creams rather than simple oil infusions. Pyrrolizidine-alkaloid control remains an important raw-material safety issue.

·       Wound healing effects of a Symphytum herb extract cream: randomized, controlled double-blind study. PMID: 18157595; DOI: 10.1007/s10354-007-0474-y.

·       Barna M, et al. Randomized double-blind study: wound-healing effects of a Symphytum herb extract cream in children. Arzneimittelforschung. 2012;62(6):285-289. PMID: 22549241; DOI: 10.1055/s-0032-1308981. Affiliation: Charles University of Prague.

·       In vivo wound healing effects of Symphytum officinale leaves extract in different topical formulations. PMID: 22570943. University affiliation: Universidade Federal dos Vales do Jequitinhonha e Mucuri.

Plantain (Plantago major)

Plantago contains iridoid glycosides, phenolic compounds, flavonoids, polysaccharides and other constituents. Wound-related evidence is predominantly preclinical and heterogeneous; this supports a traditional/scientific rationale but not strong clinical inference for an oil infusion.

·       Cardoso FCI, et al. The Effect of Plantago major on Wound Healing in Preclinical Studies: A Systematic Review. Wound Manag Prev. 2021;67(1):27-34. PMID: 33448940. University of Campinas.

·       Topical Intervention of Natural Products Applied in Patients with Pressure Injuries: A Scoping Review. PMID: 36806281. Included Plantago major among evaluated topical natural products.

Oat (Avena sativa)

Colloidal oatmeal has human and mechanistic evidence for dry and compromised skin, including effects on epidermal differentiation, tight-junction/lipid-regulation pathways, moisturization and barrier measures. OHO oat-infused oil should not be assumed to contain the same spectrum or concentration of constituents as colloidal oatmeal.

·       Ilnytska O, et al. Colloidal Oatmeal (Avena sativa) Improves Skin Barrier Through Multi-Therapy Activity. J Drugs Dermatol. 2016;15(6):684-690. PMID: 27272074.

·       Pazyar N, et al. Oatmeal in dermatology: a brief review. Indian J Dermatol Venereol Leprol. 2012;78(2):142-145. PMID: 22421643; DOI: 10.4103/0378-6323.93629. University affiliation: Jundishapur University of Medical Sciences.

St. John's Wort (Hypericum perforatum)

Hypericum contains hyperforin, hypericin and flavonoid constituents and has topical wound/skin literature. Photosensitivity associated with hypericin and preparation-dependent chemistry should be considered in formulation and labeling.

·       The potential role of Hypericum perforatum in wound healing: A literature review on phytochemicals, pharmacological approaches, and mechanistic perspectives. PMID: 38600756; DOI: 10.1002/ptr.8204.

·       Effects of Essential Oils on Scars and Wound Healing: A Systematic Review. PMID: 36070793. This review included a Hypericum-Calendula oil topical agent among the limited human literature.

Tea tree (Melaleuca alternifolia)

Tea tree oil contains terpinen-4-ol and other terpenes with laboratory antimicrobial and inflammatory-pathway activity. Human dermatology trials exist, but systematic reviews characterize the clinical evidence as limited and emphasize allergic/contact-dermatitis risk.

·       Pazyar N, et al. A review of applications of tea tree oil in dermatology. Int J Dermatol. 2013;52(7):784-790. PMID: 22998411; DOI: 10.1111/j.1365-4632.2012.05654.x. University affiliation: Jundishapur University of Medical Sciences.

·       Tea tree oil: a systematic review of randomized clinical trials. PMID: 10800248.

Turmeric / curcumin (Curcuma longa)

Curcuminoids, particularly curcumin, are extensively studied for antioxidant and inflammatory signaling. A systematic review of human dermatologic studies found early evidence across multiple skin applications but emphasized limited study quality and the need for further trials. Oil-soluble turmeric extracts vary substantially in curcuminoid content.

·       Vaughn AR, Branum A, Sivamani RK. Effects of Turmeric (Curcuma longa) on Skin Health: A Systematic Review of the Clinical Evidence. Phytother Res. 2016;30(8):1243-1264. PMID: 27213821; DOI: 10.1002/ptr.5640. University affiliations include Drexel University and University of California, Sacramento.

Black seed (Nigella sativa)

Nigella fixed oil contains thymoquinone and other bioactive constituents. Dermatology reviews describe preclinical and clinical research involving inflammatory, microbial, pigmentation and wound-related pathways. Finished-product performance remains preparation- and concentration-dependent.

·       Hwang JR, Cartron AM, Khachemoune A. A review of Nigella sativa plant-based therapy in dermatology. Int J Dermatol. 2021;60(12):e493-e499. PMID: 33899217; DOI: 10.1111/ijd.15615. University affiliations: University of Maryland School of Medicine and SUNY Downstate.

·       A Review on the Cosmeceutical and External Applications of Nigella sativa. PMID: 29358959; PMCID: PMC5735686; DOI: 10.1155/2017/7092514. University affiliations include An-Najah National University and Tripoli University.

Neem (Azadirachta indica)

Neem contains a chemically complex mixture of limonoids and other constituents. Dermatology reviews describe antimicrobial, inflammatory, antioxidant and wound-related experimental literature, but clinical evidence and extract composition vary considerably.

·       An Insight into the Dermatological Applications of Neem: A Review on Traditional and Modern Aspect. PMID: 34961431; DOI: 10.2174/2772434416666210604105251. Chitkara University.

Arnica (Arnica montana)

Arnica contains sesquiterpene lactones and other constituents. Clinical literature on topical preparations for pain and bruising is mixed; some trials report symptom benefit while others show limited effects. Sensitization/contact allergy is a known consideration.

·       Clinical Trials, Potential Mechanisms, and Adverse Effects of Arnica as an Adjunct Medication for Pain Management. PMID: 34677487.

·       The effect of topical arnica on muscle pain: randomized, double-blind, placebo-controlled trial. PMID: 20807867; DOI: 10.1345/aph.1P071.

·       The effects of topical Arnica on performance, pain and muscle damage after intense eccentric exercise. PMID: 23947690; DOI: 10.1080/17461391.2013.829126.

Clove / eugenol (Syzygium aromaticum)

Eugenol is the principal pharmacologically important constituent of clove oil and has documented analgesic and local-anesthetic pharmacology, particularly in dentistry. These effects are scientifically relevant to ingredient selection but are drug-type effects rather than ordinary cosmetic functions.

·       Pramod K, Ansari SH, Ali J. Eugenol: a natural compound with versatile pharmacological actions. Nat Prod Commun. 2010;5(12):1999-2006. PMID: 21299140. University affiliation: Jamia Hamdard.

Spilanthes / Acmella (Acmella oleracea)

Acmella contains N-alkylamides, especially spilanthol. Reviews describe antinociceptive and anesthetic mechanisms including effects on voltage-gated sodium channels, along with inflammatory and antioxidant pathways. Most evidence is preclinical; numbing/pain-relief positioning therefore requires separate regulatory and clinical consideration.

·       Acmella oleracea for pain management. Fitoterapia. 2020. PMID: 31705952; DOI: 10.1016/j.fitote.2019.104419. Review includes university-affiliated authors and summarizes 99 eligible studies.

Frankincense / Boswellia

Boswellic acids are pentacyclic triterpenes from Boswellia gum resin and have human topical research. This evidence supports resin-extract/boswellic-acid biology but should not be attributed directly to frankincense essential oil, which has a different volatile chemical profile.

·       Pedretti A, et al. Effects of topical boswellic acid on photo and age-damaged skin: clinical, biophysical, and echographic evaluations in a double-blind, randomized, split-face study. Planta Med. 2010;76(6):555-560. PMID: 19918712; DOI: 10.1055/s-0029-1240581. Dermatology Department, University of Brescia.

Carrier oils, butters and functional materials: evidence boundary

Jojoba (Simmondsia chinensis)

Jojoba is chemically unusual among cosmetic oils because it consists predominantly of long-chain wax esters. Dermatology reviews describe emollient/moisturizing use and report anti-inflammatory and wound-related research, while emphasizing that applications vary by preparation.

·       Pazyar N, et al. Jojoba in dermatology: a succinct review. G Ital Dermatol Venereol. 2013;148(6):687-691. PMID: 24442052. University affiliation: Jundishapur University of Medical Sciences.

·       Gad HA, et al. Jojoba Oil: An Updated Comprehensive Review on Chemistry, Pharmaceutical Uses, and Toxicity. Polymers (Basel). 2021. PMID: 34073772.

Sunflower oil (Helianthus annuus)

Sunflower oil literature supports an emollient/barrier rationale, especially for linoleic-acid-rich material. Linoleic acid can be incorporated into epidermal lipids and has been associated with restoration of impaired barrier function in experimental work. More recent dermatology literature describes effects on hydration and transepidermal water loss, but also cautions that high-oleic oils can behave differently; therefore OHO high-oleic sunflower oil is used primarily as a stable carrier/emollient unless the specific material has supporting data.

·       Prottey C, et al. The repair of impaired epidermal barrier function in rats by the cutaneous application of linoleic acid. Br J Dermatol. 1976. PMID: 1252336.

·       Eichenfield LF, McCollum A, Msika P. The benefits of sunflower oleodistillate in pediatric dermatology. Pediatr Dermatol. 2010. PMID: 20199440. University affiliation: University of California San Diego School of Medicine.

·       Mechanistic insights and clinical evidence of Helianthus annuus seed oil for dermatological applications: a narrative review. PMID: 40783675. Note: review distinguishes linoleic- and oleic-acid effects.Mango butter, cocoa butter, beeswax, cetyl alcohol, MCT/fractionated coconut oil, castor oil, sesame oil, shea butter, vitamin E and similar materials contribute primarily through emollience, occlusion, rheology, slip, oxidation control or delivery characteristics in these formulas. Where disease-oriented literature exists for a constituent, it should not automatically be converted into a therapeutic claim for the finished product. The strongest scientific justification for these materials in the OHO platform is often physicochemical and dermatologic vehicle function rather than condition-specific efficacy.

How to cite this evidence in individual product sections

Each formula section should read its ingredient rationale together with this supplement. A citation supporting a botanical or carrier establishes scientific plausibility for that ingredient or preparation; it does not establish that the complete OHO formula treats the named disease. Where a study used a preparation materially different from OHO - for example, colloidal oatmeal instead of oat-infused oil, boswellic acids instead of frankincense essential oil, or linoleic-rich sunflower oil instead of high-oleic sunflower oil - that distinction is controlling.

Selected NIH/PubMed reference index

1.          Pazyar N, et al. Jojoba in dermatology: a succinct review. G Ital Dermatol Venereol. 2013;148(6):687-691. PMID: 24442052. University affiliation: Jundishapur University of Medical Sciences.

2.          Gad HA, et al. Jojoba Oil: An Updated Comprehensive Review on Chemistry, Pharmaceutical Uses, and Toxicity. Polymers (Basel). 2021. PMID: 34073772.

3.          Prottey C, et al. The repair of impaired epidermal barrier function in rats by the cutaneous application of linoleic acid. Br J Dermatol. 1976. PMID: 1252336.

4.          Eichenfield LF, McCollum A, Msika P. The benefits of sunflower oleodistillate in pediatric dermatology. Pediatr Dermatol. 2010. PMID: 20199440. University affiliation: University of California San Diego School of Medicine.

5.          Mechanistic insights and clinical evidence of Helianthus annuus seed oil for dermatological applications: a narrative review. PMID: 40783675. Note: review distinguishes linoleic- and oleic-acid effects.

6.          Srivastava JK, Shankar E, Gupta S. Chamomile: A herbal medicine of the past with bright future / related chamomile bioactivity literature. Key PubMed review: PMID 16628544; DOI: 10.1002/ptr.1900.

7.          Apigenin and its dermatological applications: A comprehensive review. PMID: 35998830. Review conclusion: preclinical dermatologic evidence is substantial, but clinical studies of apigenin itself are lacking.

8.          Russell K, Jacob SE. Bisabolol. Dermatitis. 2010;21(1):57-58. PMID: 20137740. University affiliation: University of California San Diego School of Medicine. Included only to document bisabolol as a naturally occurring German-chamomile constituent, not as an OHO isolated ingredient.

9.          Givol O, et al. A systematic review of Calendula officinalis extract for wound healing. Wound Repair Regen. 2019;27(5):548-561. PMID: 31145533; DOI: 10.1111/wrr.12737. University affiliations include Tel Aviv University, University of Tasmania and University of Notre Dame Australia.

10.     Leach MJ. Calendula officinalis and Wound Healing: A Systematic Review. Wounds. 2008;20(8):236-243. PMID: 25941793. University affiliation: University of South Australia.

11.     Witkowska K, et al. Topical Application of Centella asiatica in Wound Healing: Recent Insights into Mechanisms and Clinical Efficacy. Pharmaceutics. 2024;16(10):1252. PMID: 39458583; PMCID: PMC11510310; DOI: 10.3390/pharmaceutics16101252. Poznan University of Medical Sciences.

12.     A Systematic Review of the Effect of Centella asiatica on Wound Healing. PMID: 35328954. Four clinical trials were included.

13.     Wound healing effects of a Symphytum herb extract cream: randomized, controlled double-blind study. PMID: 18157595; DOI: 10.1007/s10354-007-0474-y.

14.     Barna M, et al. Randomized double-blind study: wound-healing effects of a Symphytum herb extract cream in children. Arzneimittelforschung. 2012;62(6):285-289. PMID: 22549241; DOI: 10.1055/s-0032-1308981. Affiliation: Charles University of Prague.

15.     In vivo wound healing effects of Symphytum officinale leaves extract in different topical formulations. PMID: 22570943. University affiliation: Universidade Federal dos Vales do Jequitinhonha e Mucuri.

16.     Cardoso FCI, et al. The Effect of Plantago major on Wound Healing in Preclinical Studies: A Systematic Review. Wound Manag Prev. 2021;67(1):27-34. PMID: 33448940. University of Campinas.

17.     Topical Intervention of Natural Products Applied in Patients with Pressure Injuries: A Scoping Review. PMID: 36806281. Included Plantago major among evaluated topical natural products.

18.     Ilnytska O, et al. Colloidal Oatmeal (Avena sativa) Improves Skin Barrier Through Multi-Therapy Activity. J Drugs Dermatol. 2016;15(6):684-690. PMID: 27272074.

19.     Pazyar N, et al. Oatmeal in dermatology: a brief review. Indian J Dermatol Venereol Leprol. 2012;78(2):142-145. PMID: 22421643; DOI: 10.4103/0378-6323.93629. University affiliation: Jundishapur University of Medical Sciences.

20.     The potential role of Hypericum perforatum in wound healing: A literature review on phytochemicals, pharmacological approaches, and mechanistic perspectives. PMID: 38600756; DOI: 10.1002/ptr.8204.

21.     Effects of Essential Oils on Scars and Wound Healing: A Systematic Review. PMID: 36070793. This review included a Hypericum-Calendula oil topical agent among the limited human literature.

22.     Pazyar N, et al. A review of applications of tea tree oil in dermatology. Int J Dermatol. 2013;52(7):784-790. PMID: 22998411; DOI: 10.1111/j.1365-4632.2012.05654.x. University affiliation: Jundishapur University of Medical Sciences.

23.     Tea tree oil: a systematic review of randomized clinical trials. PMID: 10800248.

24.     Vaughn AR, Branum A, Sivamani RK. Effects of Turmeric (Curcuma longa) on Skin Health: A Systematic Review of the Clinical Evidence. Phytother Res. 2016;30(8):1243-1264. PMID: 27213821; DOI: 10.1002/ptr.5640. University affiliations include Drexel University and University of California, Sacramento.

25.     Hwang JR, Cartron AM, Khachemoune A. A review of Nigella sativa plant-based therapy in dermatology. Int J Dermatol. 2021;60(12):e493-e499. PMID: 33899217; DOI: 10.1111/ijd.15615. University affiliations: University of Maryland School of Medicine and SUNY Downstate.

26.     A Review on the Cosmeceutical and External Applications of Nigella sativa. PMID: 29358959; PMCID: PMC5735686; DOI: 10.1155/2017/7092514. University affiliations include An-Najah National University and Tripoli University.

27.     An Insight into the Dermatological Applications of Neem: A Review on Traditional and Modern Aspect. PMID: 34961431; DOI: 10.2174/2772434416666210604105251. Chitkara University.

28.     Clinical Trials, Potential Mechanisms, and Adverse Effects of Arnica as an Adjunct Medication for Pain Management. PMID: 34677487.

29.     The effect of topical arnica on muscle pain: randomized, double-blind, placebo-controlled trial. PMID: 20807867; DOI: 10.1345/aph.1P071.

30.     The effects of topical Arnica on performance, pain and muscle damage after intense eccentric exercise. PMID: 23947690; DOI: 10.1080/17461391.2013.829126.

31.     Pramod K, Ansari SH, Ali J. Eugenol: a natural compound with versatile pharmacological actions. Nat Prod Commun. 2010;5(12):1999-2006. PMID: 21299140. University affiliation: Jamia Hamdard.

32.     Acmella oleracea for pain management. Fitoterapia. 2020. PMID: 31705952; DOI: 10.1016/j.fitote.2019.104419. Review includes university-affiliated authors and summarizes 99 eligible studies.

Pedretti A, et al. Effects of topical boswellic acid on photo and age-damaged skin: clinical, biophysical, and echographic evaluations in a double-blind, randomized, split-face study. Planta Med. 2010;76(6):555-560. PMID: 19918712; DOI: 10.1055/s-0029-1240581. Dermatology Department, University