Few substances straddle the worlds of ancient ritual, traditional medicine, and modern industry quite like lac (ครั่ง)—the intriguing resin secreted by the lac insect, Laccifer chinensis. Known in Thai as ครั่ง and in Chinese as จุ้ยเก้ง, this natural exudate has colored textiles, sealed documents, delivered vivid reds in temple murals, and, more quietly, worked as a healing agent in traditional remedies across Asia for centuries. Today, as scientists revisit the pharmacological potential of natural compounds, lac is in the spotlight once again—not only for its rich legacy but for surprising early evidence supporting some of its traditional uses. What makes this glossy, carmine-tinted resin so special, and how can today’s health-conscious readers separate myth from material fact?
Lac has been woven into the cultural and economic fabric of Southeast Asia and the Indian subcontinent for over two millennia. Thai villagers in provinces such as Chiang Mai and Uttaradit have cultivated the resin in symbiosis with local trees, gathering it not only as a source of vibrant red dye and varnish but also as a revered healing material. In India, its role is immortalized in Ayurveda; in China, it appears in ancient materia medica. Its vivid red hue once adorned royal manuscripts and temple walls throughout Lanna and Ayutthaya, demonstrating cultural reverence for the resin in spiritual and everyday life. Today, lac persists in use, especially among practitioners of herbal Thai medicine who regard it as an astringent, wound coagulant, antifungal, and even a bone-healing agent.
Beyond its vibrant color and finish, traditional healers in Thailand, India, and China have attributed a wealth of medicinal properties to lac. The core of its therapeutic use lies in its astringency—a property that enables it to constrict tissues, staunch bleeding, and promote wound healing. Both Thai and Ayurvedic traditions recommend preparations containing lac for accelerating the closure of external wounds, addressing skin diseases such as eczema, scabies, and herpes, and as a plaster for fractured bones—where it is reputed to help ‘set’ and fortify healing. In Thailand, herbal compendia record the use of lac for the treatment of chronic ulcers, minor hemorrhages, and even as an ingredient in medicinal tooth powders for its antimicrobial qualities. Ethnographic accounts note that traditional practitioners may blend powdered lac with other botanicals to create pastes and plasters designed for direct application, leveraging its stickiness and mineral content to form protective barriers over delicate skin.
Modern pharmacological research has only begun to decode these ancient claims. According to an open-access review published in 2022, lac is a complex biological product made up of resins, natural dyes (notably laccaic acid), and waxes, with dozens of identified bioactive compounds. The resin itself consists largely of polyterpene esters and hydroxyl fatty acids, while the dye is an anthraquinone derivative known for its deep red coloration and mild antimicrobial properties (PMC9784800). Studies referenced in authoritative reviews like “The Medicinal Uses of Laksha” point to its astringent, anti-inflammatory, and coagulant qualities—markers aligning with its folk use as a wound dressing and hemostatic agent (artofvedas.com).
In terms of pharmacological action, lac (or “laksha” as it’s known in Sanskrit) demonstrates mild antimicrobial effects owing to the presence of laccaic acids, as well as a potential for modulating local inflammation. Laboratory research from India found that certain components of lac inhibit common skin pathogens, including species of staphylococcus, helping explain the resin’s historical use for treating infected wounds and ulcers. Its anti-inflammatory activity, combined with barrier-forming stickiness, could contribute to the rapid healing of minor cuts and abrasions observed by traditional practitioners (medthai.com). Thai herbal medicine authorities recommend lac particularly when healing slow-to-close wounds or when environmental conditions create a high risk of secondary infections.
Perhaps most remarkable is lac’s traditional association with the healing of fractures. In Ayurvedic medicine, lac is described as “Bhagnasandhana” (bone healer)—used in external application alongside oils to support the mending of broken bones, and sometimes internalized in microquantities (though this use is contentious and discouraged without physician oversight). While robust clinical trials on humans are lacking, some animal studies suggest that lac preparations may promote mineralization or reduce local inflammation in the context of bone healing. However, such findings remain preliminary and require controlled clinical evaluation for definitive confirmation.
Beyond injuries, folk medicine lists an array of uses for lac: it is said to calm persistent hiccups, relieve dermatological itching, and assist in the management of chronic ulcers. In Thailand’s northern herbal compendia, lac preparations are still used in topical skin remedies, and occasionally included in oral formulations reputed to support liver function and control mild obesity, although clinical validation here is particularly thin (Wikipedia). In China, extracts of lac have also been utilized in traditional pharmacopeias for treating “blood stasis” conditions and even joint pain.
Crucially, for today’s general readers, it’s important to recognize that while traditional use is rich and fascinating, scientific substantiation remains limited to laboratory and animal data, with very few controlled clinical trials supporting specific medicinal claims. The World Health Organization recognizes lac as “generally regarded as safe” for external use in food and cosmetics—and shellac, a purified form, is widely used as a pharmaceutical glaze. Nevertheless, internal medicinal use should be approached with caution, as impurities during crude extraction may introduce contaminants, and allergic reactions, though rare, could occur. Modern Thai herbalists (สมุนไพรไทย) and community healthcare workers strongly advise that patients consult qualified traditional medicine practitioners or physicians before attempting to use lac, particularly for persistent or severe health issues.
One of the enduring strengths of lac is its environmental and social sustainability. While wild collection played a major role historically, community cultivation of host plants and lac insects in northern Thailand provides an important supplementary income stream to rural families, and helps sustain biodiversity. Lac host plants in Thailand and neighboring countries include varieties of Ziziphus, Butea, Ficus, and others, the health of which supports not only the insects but also broader ecosystems. The lacquerware industry—renowned for splendidly finished bowls, betel boxes, and ornamentation—has both preserved ancient artistry and kept the knowledge of lac alive within contemporary Thai society (samunpri.com).
The future of lac-based remedies is poised at an interesting juncture. On one hand, the revival of natural medicines is driving new interest in its healing applications and ecological role. On the other, scientists caution that much research is needed to translate ancient wisdom into modern, standardized healthcare—especially regarding dosage, efficacy, and safety of medicinal uses. Some researchers are actively working to isolate the bioactive constituents responsible for lac’s purported healing, antimicrobial, and anti-inflammatory effects, hoping to unlock new therapies from this age-old remedy (pmc.ncbi.nlm.nih.gov). Innovations in biotechnology may also one day clarify the genetics behind lac insect resin production, enabling sustainable cultivation and possibly more targeted medicinal forms.
What does this mean for health-conscious Thai readers seeking to benefit from traditional plant and insect-based therapies? First, lac remains a culturally significant and widely used remedy for minor wounds, slow-healing ulcers, and some dermatological conditions—the practical application most supported both by tradition and emerging evidence. Given its low toxicity and history of use as a food glaze and pharmaceutical coating, applying lac-based ointments externally is generally safe when sourced from reputable suppliers. However, the use of lac for bone healing, internal ingestion, or as a treatment for chronic or systemic illnesses should always be discussed with healthcare professionals, and must not replace modern medical interventions for serious injuries or infections.
In summary, lac exemplifies the fascinating intersection of Thai culture, ancient healing wisdom, and modern scientific inquiry. As an artisanal product, it links rural communities to global markets. As a traditional medicine, it demonstrates the resourcefulness and observational skill of earlier generations. And as a subject of contemporary research, it stands as a testament both to the value of tradition and to the need for rigorous validation. For those interested in integrating lac into their health routines, the best approach is to use it as part of well-established practices for topical wound care, in partnership with medical advice, and always with respect for the complex ecology and history from which it springs.
Sources:
- Unraveling the Role of Lac Insects in Providing Natural Industrial Products (PMC9784800)
- The Medicinal Uses of Laksha (artofvedas.com)
- Lac (resin) - Wikipedia
- สมุนไพรไทย–ครั่ง (samunpri.com)
- ครั่ง–องค์ความรู้สมุนไพร (medthai.com)
Call to action: If you are intrigued by the potential of traditional remedies like lac, consider integrating them thoughtfully into your self-care practice for minor cuts or skin issues—always sourcing from reputable vendors and consulting with traditional medicine practitioners or healthcare professionals. Continue to value both the wisdom of our ancestors and the rigor of modern science, embracing the best of both worlds for your health.
This article is for educational purposes and should not be considered medical advice. Consult healthcare professionals before initiating any traditional or herbal remedy, especially in the case of persistent, severe, or systemic health concerns.