Potential Health Benefits of Cloves
Cloves (Eugenia caryophyllata) are a popular spice derived from the dried flower bud of the clove tree. For thousands of years, dating back to the ancient Chinese, cloves have been used for spice, fragrance, and medicine.
Most researchers attribute the health-promoting attributes of cloves to eugenol. Eugenol is a polyphenol. Similar to other polyphenols like the flavonoids and catechins found in fruits and green tea, eugenol possesses potent antioxidant and anti-inflammatory properties. Eugenol is also responsible for the pleasant odor and distinct taste of cloves.
Potential Benefits of Cloves for Musculoskeletal Health
1. Eugenol is an Antioxidant
Oxidative damage is a key mechanism that causes premature aging of joint, muscle, bone, and tendon tissue. (Ito et al., 2005; Leem et al., 2011; Chogo & Crank, 1981). Eugenol combats oxidative damage through multiple pathways:
- Eugenol can deactivate highly reactive metals, such as iron and arsenic, that attempt to steal electrons from vital proteins, DNA, and good fats. This theft of electrons can cause irreparable harm to these important structures.
- Eugenol can shield cell walls from free radical attack. If the cell wall is damaged by the free radical onslaught, all the contents inside the cell may leak out, causing the cell to undergo programmed cell death.
- Eugenol disarms high-energy oxygen molecules that injure cell proteins and DNA.
Indian investigators examined the influence of an extract rich in eugenol on a rat model of osteoporosis. The results suggested that the treatment group’s bone density and bone tensile strength improved compared to the non-intervention group. The authors concluded that eugenol’s antioxidant and anti-inflammatory properties likely contributed to their findings (Nat Prod Res, 2012).
2. Eugenol is a Natural Pain Killer
Pain is a devastating symptom of musculoskeletal disease. Eugenol potentially inhibits pain by weakening the transmission of pain signals from nerves within joints to the nerve receptors in the spinal cord and brain. Research suggests that eugenol alters the conduction potential over nerves, thereby decreasing the intensity and frequency of pain signals. (Li et al., 2007; Inoue et al., 2012; Lee et al., 2005; Ferland et al., 2012)
Investigators at the University of Montreal explored the antinociceptive effects of eugenol on a rat model of arthritis. The findings indicated that eugenol improved the rats’ gait pattern and reduced the level of neuropeptides that correlate to pain generation (Ferland et al., 2012).
3. Eugenol is an Anti-Inflammatory
Chronic low-grade inflammation is a driving force behind chronic joint, bone, tendon, and muscle injury. (Leem et al., 2011; Daniel et al., 2009; Kim et al., 2003; Bachiega et al., 2012) Eugenol inhibits the same inflammatory pathway targeted by commonly prescribed NSAIDs.
Investigation implies that eugenol reduces:
- The synthesis of inflammation-inducing signaling molecules, like cytokines and interleukins.
- The activity of pro-inflammatory enzymes, like COX-2.
- The production of pain-inducing substances, such as prostaglandins.
Brazilian researchers used a rat model of arthritis to assess the effect of eugenol on clinical signs of arthritis. The results suggested that eugenol was able to reduce signs of inflammation, such as swelling, redness, and pro-inflammatory cytokine levels (Grespan et al., 2012).
Precautions
Eugenol is generally recognized as safe when consumed in usual culinary and herbal doses. (Expert Committee on Food Additives, 1982; Hartnoll et al., 1993). As with any supplementation, consult your healthcare provider prior to use if you are pregnant, nursing, taking any medications, or have any medical conditions. Discontinue use and consult your doctor if any adverse reactions occur.
References
- Chogo, J. B., & Crank, G. (1981). Chemical composition and biological activity of the Tanzanian plant Ocimum suave. Journal of Natural Products, 42, 308–311.
- Daniel, A. N., Sartoretto, S. M., Schmidt, G., Caparroz-Assef, S. M., Bersani-Amado, C. A., & Cuman, R. K. N. (2009). Anti-inflammatory and antinociceptive activities of eugenol essential oil in experimental animal models. Revista Brasileira de Farmacognosia, 19, 212–217.
- Expert Committee on Food Additives. (1982). Evaluation of certain food additives and contaminants. WHO Technical Report Series 683. Geneva, Switzerland: WHO Press.
- Ferland, C. E., Beaudry, F., & Vachon, P. (2012). Antinociceptive effects of eugenol evaluated in a monoiodoacetate-induced osteoarthritis rat model. Phytotherapy Research, 26(9), 1278-1285.
- Grespan, R., et al. (2012). Anti-arthritic effect of eugenol on collagen-induced arthritis experimental model. Biological and Pharmaceutical Bulletin, 35(10), 1818-1820.
- Hartnoll, G., Moore, D., & Douek, D. (1993). Near fatal ingestion of oil of cloves. Archives of Disease in Childhood, 69, 392–393.
- Inoue, M., Fujita, T., Goto, M., & Kumamoto, E. (2012). Presynaptic enhancement by eugenol of spontaneous excitatory transmission in rat spinal substantia gelatinosa neurons is mediated by transient receptor potential A1 channels. Neuroscience (in press).
- Ito, M., Murakami, K., & Yoshino, M. (2005). Antioxidant action of eugenol compounds: Role of metal ion in the inhibition of lipid peroxidation. Food and Chemical Toxicology, 43, 461–466.
- Kim, S. S., Oh, O. J., Min, H. Y., Park, E. J., Kim, Y., Park, H. J., Han, Y. N., & Lee, S. K. (2003). Eugenol suppresses cyclooxygenase-2 expression in lipopolysaccharide-stimulated mouse macrophage RAW264.7 cells. Life Sciences, 73, 337–348.
- Leem, H.-H., Kim, E.-O., Seo, M.-J., & Choi, S.-W. (2011). Antioxidant and anti-inflammatory activities of eugenol and its derivatives from clove (Eugenia caryophyllata Thunb.). Journal of Korean Society of Food Science and Nutrition, 40, 1361–1370.
- Li, H. Y., Park, C. K., Jung, S. J., Choi, S. Y., Lee, S. J., Park, K., Kim, J. S., & Oh, S. B. (2007). Eugenol inhibits K+ currents in trigeminal ganglion neurons. Journal of Dental Research, 86, 898–902.
