Horse ointment, known as horse oil and horse fat, is a topical formulation derived from subcutaneous fat of horses.[1] Due to its thickness and viscosity, horse ointment is intended for topical use on human skin and mucous membranes to moisturize and increase the restoration of damaged skin. Horse ointment was traditionally prepared and used in ancient China for the treatment of qi deficiency,[2] hemorrhoids, burns, and xeroderma.[3] Due to the amount of fatty acids in horse ointment, which is similar to that of human skin fat, it can penetrate through the surface of skin. Nowadays, it is commonly applied to skin for the purpose of soothing redness and irritation. It is considered a natural skincare product with low risks of sensitization and irritation and is safe for people of all ages, including infants and seniors.
Use of horse ointment in ancient Chinese medicine
editHorse ointment is used as preparation for the treatment of skin conditions. Horse ointment originated in China and has existed for over 4,000 years. Its usage was recorded in some ancient Chinese medical books. Lingshu Jing was the first pharmacopoeia that included information about the moisturizing properties and effectiveness of horse ointment in the treatment of milia. Li Shizhen, a Chinese physician and writer of Compendium of Materia Medica, mentioned the use of horse ointment in the treatment of dyschromia, eczema, and burns. The doctor Tao Hongjing also mentioned that horse oil can help to promote hair growth in the Compendium.
Ingredients and their functions
editThe following table summarizes the main ingredients found in horse ointment formulations, their effects on skin, as well as their safety scores, which were determined by the US Environmental Working Group (EWG).[4] Horse oil creams of different brands may have variations in their ingredients.
The ingredient safety points are quoted from the EWG US Environmental Working Group. They are used to indicate the potential risks of long-term use of the ingredient to human skin and health. Ingredient safety points range from 1-10, with 10 representing the highest risk and 1 representing the lowest risk.
| Ingredients | Role | Ingredient safety points Based on EWG
(0-10) |
| Water | Solvent | 1 |
| Cetyl Alcohol | Emulsion stabiliser, moisturizer, thickener | 1 |
| Glycerin | Moisturiser | 2 |
| Alpha-Lipoic Acid (ALA) | Antioxidant | 1 |
| Oleic acid | Moisture barrier | 1 |
| Coenzyme Q10 | Skin cells replenisher | unknown |
| Hyalurnic acid | Skin conditioner | unknown |
| Palmitic acid | Emollient | 1 |
| Collagen | Moisturiser and for regenerating and firming skin | 1 |
| Vitamin E | Antioxidant | 1-2 |
| Glycyrrhetinic acid | For calming skin and minimising irritation | 4 |
| Liquid paraffin | Emollient | 1 |
| Polysorbate 80 | Emlusifier | 1-3 |
| Horse Fat | Skin conditioning | unknown |
| Sodium ascorbyl phosphate | Antioxidant | 1 |
| Urea | Moisturiser | 1-3 |
| Dimethicone | Emollient | 1 |
| Rosemary leaf extract | Moisturiser | 1 |
| Phenoxyethanol | Fragrance, Preservative | 4 |
| Disodium/Trisodium EDTA | Chelating agent | 1 |
Overall, the safety points of ingredients commonly found in horse ointment formulations ranges between 1-4, indicating a low risk of causing skin or other health issues. Although horse ointment itself is a nature skin moisturizer, different ingredients might be added in the production process to mask the odor of horse oil as well as to add nutrients that can lessen the effects of horse ointment on skin.
Production
editThe extraction of horse oil is a process that requires the use of large-scale machines. Horse fatty tissues are first ground with a meat grinder and then mixed with water. In order to render horse oils, horse fat is first extracted in a vacuum system at a temperature between 60–110 °C. Rendered horse oil is then collected, filtered, and neutralized with 0.2% sodium hydroxide. Afterwards, it transferred to a stainless steel container in a water bath at 100 °C for 30 minutes for the precipitation of impurities.[5] Modern manufacturing of horse ointment usually involves purification to remove the odor of horse oil, which enables it to be a cosmetic product widely used nowadays.[6]
Composition and chemistry
editA typical high-purity grade of horse ointment is composed predominantly of unsaturated acids. Compared to saturated acids, unsaturated acids are more suitable for skin applications. Two substances in horse ointments have a larger influence on its impact on skin, namely alphalinolenic acid and linoleic acid. Alphalinolenic acid is an omega-3 fatty acid that exerts anti-inflammatory effects, while linolenic acid is an omega-6 fatty acid that moisturizes the skin and reduces inflammatory mediators.[7] In addition to its effects on skin, a recent study discovered that horse ointments could also protect against oxidative stress. Experimental results showed that horse ointments absorb UVB radiation and remove reactive oxygen species, thus protecting human HaCaT keratinocytes from UVB-induced oxidative stress and preventing cell structural damage, skin necrosis, and aging.[8]
Cosmetic use
editPreventing acne and fading scars
editHorse ointment contains vitamin F, which exerts a natural anti-inflammatory effect and prevents flare-ups of acne. It can also increase the repairing of damaged skin cells and speed up the fading of scars.[9]
Reducing pore size
editSome horse ointment formulas contain natural moisturizers extracted from plants, such as rosemary, horsetail, hops, pine, and lemon. These natural moisturizers are able to repair skin, which is a necessary property for increasing skin metabolism, maintaining skin health, as well as reducing pore size.
Hydration of skin
editHorse ointment contains coenzyme Q10, hyaluronic acid, and collagen, which can maintain the natural moisture barrier of the skin to prevent its water loss. Oleic acid and sea shark essence in horse oil disturbs the natural lipid bilayer of the cuticle and allows penetration into the skin.[10]
Reduction of formation of spots and wrinkles
editHorse oil contains sophorolipids and natural ingredients such as horsetail and pine hops, which promote the synthesis of collagen in the skin and thus maintain elasticity and prevent wrinkle formation.[11]
Promotion of hair growth
editLiposomes in horse oil stimulate hair follicles to enter the anagen phase of the hair growth cycle, thus shortening the time for hair growth.[12]
Studies on horse ointments
editHorse oil is one of the most common natural moisturizing ingredients in cosmetic products in Asian countries. It has been claimed to have antibacterial, anti-inflammatory, and antipruritic effects on the skin. However, most studies related to the efficacy of horse oil are written in Japanese or Korean without any English translations, thus making it difficult for dermatologists to analyze and discuss the findings.[13]
Ethical concerns
editHorse oil is extracted from a mixture of fat from the manes, tail root, and abdomens of horses in alpine regions, which raises ethical concerns. Some vegetarians and animal-rights activists hold firm to the belief that using horses for the production of horse ointment is cruel and unsustainable.
Market value
editAfter refining, horse oil is a raw material for the production of high-end cosmetics that can be exchanged in the market. The development and production of horse oil ointment and other associated cosmetic products has extended the chain of horse product development, increasing the output value each year. Horse ointment is now widely produced, although it is mainly produced in the Kyushu area.
References
edit- ^ Yu, Jiuwang; Wang, Lu; Ding, Jiang; Wu, Lan (2021-12-01). "Extraction of Oleic Acid from Animals Oil and Its Anti-inflammatory Effect on Network Pharmacology". Iranian Journal of Science and Technology, Transactions A: Science. 45 (6): 1905–1913. doi:10.1007/s40995-021-01168-3. ISSN 2364-1819. S2CID 238709404.
- ^ "Journal of Beijing University of Traditional Chinese Medicine", No. 2, 1994 | Chen Wenwei".
- ^ Qiburi, Qiburi; Ganbold, Tsogzolmaa; Bao, Qingming; Da, Man; Aoqier, Aoqier; Temuqile, Temuqile; Baigude, Huricha (2020-01-10). "Bioactive components of ethnomedicine Eerdun Wurile regulate the transcription of pro-inflammatory cytokines in microglia". Journal of Ethnopharmacology. 246: 112241. doi:10.1016/j.jep.2019.112241. ISSN 0378-8741. PMID 31533078. S2CID 202686727.
- ^ "EWG Skin Deep® Cosmetics Database". EWG. Retrieved 2023-04-03.
- ^ Cho, Man Jae; Kim, Hyun Jung (2020-02-01). "Effects of rendering and α-tocopherol addition on the oxidative stability of horse fat". Food Science and Biotechnology. 29 (2): 169–177. doi:10.1007/s10068-019-00653-1. ISSN 2092-6456. PMC 6992833. PMID 32064125.
- ^ KR 101529864, Lee, Chung-Woo, "Method for purifying horse oil", published 2015-06-19
- ^ "Efficacy of horse oil on lipopolysaccharide-induced inflammation in human keratinocytes".
- ^ Piao, Mei; Kang, Kyoung; Zhen, Ao; Kang, Hee; Koh, Young; Kim, Bong; Hyun, Jin (2019). "Horse Oil Mitigates Oxidative Damage to Human HaCaT Keratinocytes Caused by Ultraviolet B Irradiation". International Journal of Molecular Sciences. 20 (6): 1490. doi:10.3390/ijms20061490. PMC 6471125. PMID 30934595.
- ^ Goik, Urszula; Goik, Tomasz; Załęska, Izabela (April 2019). "The Properties and Application of Argan Oil in Cosmetology". European Journal of Lipid Science and Technology. 121 (4): 1800313. doi:10.1002/ejlt.201800313. ISSN 1438-7697. S2CID 104351204.
- ^ Yu, Jiuwang; Wang, Lu; Ding, Jiang; Wu, Lan (2021-12-01). "Extraction of Oleic Acid from Animals Oil and Its Anti-inflammatory Effect on Network Pharmacology". Iranian Journal of Science and Technology, Transactions A: Science. 45 (6): 1905–1913. doi:10.1007/s40995-021-01168-3. ISSN 2364-1819. S2CID 238709404.
- ^ Maeng, Yoojae; Kim, Kyoung Tae; Zhou, Xuan; Jin, Litai; Kim, Ki Soo; Kim, Young Heui; Lee, Suyeon; Park, Ji Ho; Chen, Xiuyu; Kong, Mingxia; Cai, Lu; Li, Xiaokun (September 2018). "A novel microbial technique for producing high-quality sophorolipids from horse oil suitable for cosmetic applications". Microbial Biotechnology. 11 (5): 917–929. doi:10.1111/1751-7915.13297. PMC 6116743. PMID 30022625.
- ^ "The effect of liposomed horse oil on the hair growth in C57BL/6 mic". ResearchGate.
- ^ Hon, K. L.; Kung, J. S.; Ng, W. G.; Leung, T. F. (2018). "Emollient treatment of atopic dermatitis: latest evidence and clinical considerations". Drugs in Context. 7: 212530. doi:10.7573/dic.212530. PMC 5908267. PMID 29692852.