Carotenoids are brilliantly colored organic pigments found in plants. Common colors are red, orange, and yellow. In plants, carotenoids play two pivotal roles: facilitating light absorption for use in energy synthesis and protecting plant structures from UV radiation damage.
Humans do not produce carotenoids; robust amounts can only be gained through diet. The most common carotenoids are:
- Alpha carotene
- Beta carotene
- Cryptoxanthin
- Lutein
- Zeaxanthin
- Lycopene
Carotenoids are fat-soluble, meaning they can penetrate unhealthy fat cells that harbor many of the toxins that compromise our well-being.
How Do Carotenoids Support Musculoskeletal Health?
Oxidative damage is a key mechanism that causes premature aging of joint, muscle, bone, and tendon tissue. Carotenoids are powerful antioxidants that help shield the fat in cell walls from free radical attack. If the cell wall is damaged by free radical onslaught, all the contents inside the cell may leak out, causing the cell to undergo programmed cell death. Additionally, carotenoids disarm high-energy oxygen molecules, called reactive oxygen species, that injure cell proteins and DNA.
Chronic low-grade inflammation is a driving force behind chronic joint, bone, tendon, and muscle injury. Carotenoids inhibit the same inflammatory pathway targeted by commonly prescribed NSAIDs. Investigation suggests carotenoids reduce: (1) the synthesis of inflammation-inducing signaling molecules, like cytokines and interleukins, (2) the activity of the pro-inflammatory enzymes, like COX-2, and (3) the production of pain-inducing substances, such as prostaglandins.
4 Musculoskeletal Benefits of Carotenoids
1. Carotenoids Support Joint Health
Multiple population-based epidemiological studies have observed an association between carotenoid intake and reduced risk of osteoarthritis. In a study looking at a cohort of participants from Johnson County, North Carolina, scientists identified a 70% reduction in the likelihood of knee arthritis in participants in the top third of lutein or beta-cryptoxanthin consumption (De Roos et al., 2001).
2. Carotenoids Boost Bone Health
Japanese researchers examined the association of beta-cryptoxanthin, a type of carotenoid, and osteoporosis in post-menopausal subjects. The investigators found that higher serum concentrations of beta-cryptoxanthin (1.88-10.53 μM) were associated with a lower risk of developing osteoporosis (Sugiura et al., 2016).
3. Carotenoids Enhance Muscle Health
Researchers at Johns Hopkins University reviewed population studies that examined the relationship between muscle strength and carotenoids. The authors concluded that carotenoids or carotenoid-rich foods are protective against a decline in muscle strength and walking disability among older community-dwelling adults (Semba et al., 2007).
4. Carotenoids Promote Tendon Health
Investigators at the University of Chicago used a chicken model of tendon injury to explore the relationship between vitamin A supplementation, beta-carotene supplementation, and tendon repair. The authors concluded that beta-carotene and vitamin A supplementation increased the breaking strength of composite tendon wounds (Greenwald et al., 1990).
Precautions
No upper limit of carotenoids consumed from natural food has been reported. However, high-dose beta-carotene supplementation has been associated with serious risks. Some research has shown that supplementing with high doses of beta-carotene might raise the risk of certain cancers and heighten the chance of death from all causes.
References
- Cerhan, J. R., Saag, K. G., Merlino, L. A., Mikuls, T. R., & Criswell, L. A. (2003). Antioxidant micronutrients and risk of rheumatoid arthritis in a cohort of older women. American Journal of Epidemiology, 157(4), 345-354. https://doi.org/10.1093/aje/kwf205
- De Roos, A. J., Arab, L., Renner, J. B., Craft, N., Luta, G., Helmick, C. G., & Jordan, J. M. (2001). Serum carotenoids and radiographic knee osteoarthritis: The Johnston County osteoarthritis project. Public Health Nutrition, 4(5), 935-942. https://doi.org/10.1079/PHN2001132
- Granado-Lorencio, F., Lagarda, M. J., Garcia-López, F. J., Sánchez-Siles, L. M., Blanco-Navarro, I., Alegría, A., & Barberá, R. (2014). Effect of b-cryptoxanthin plus phytosterols on cardiovascular risk and bone turnover markers in post-menopausal women: A randomized crossover trial. Nutrition, Metabolism & Cardiovascular Disease, 24, 1090-1096.
- McAlindon, T. E., Jacques, P., Zhang, Y., Hannan, M. T., Aliabadi, P., Weissman, B., & Felson, D. T. (1996). Do antioxidant micronutrients protect against the development and progression of knee osteoarthritis? Arthritis & Rheumatism, 39(4), 648-656.
- Pablo, P., Dietrich, T., & Karlson, E. W. (2007). Antioxidants and other novel cardiovascular risk factors in subjects with rheumatoid arthritis in a large population sample. Arthritis & Rheumatism, 57(6), 953-962. https://doi.org/10.1002/art.22912
- Semba, R. D., Lauretani, F., Ferrucci, L. (2007). Carotenoids as protection against sarcopenia in older adults. Archives of Biochemistry and Biophysics, 458(2), 141-145.
- Sugiura, M., Nakamura, M., Ogawa, K., Ikoma, Y., Yano, M., & Momiyama, Y. (2016). High vitamin C intake with high serum β-cryptoxanthin associated with lower risk for osteoporosis in post-menopausal Japanese female subjects: Mikkabi cohort study. Journal of Nutritional Science and Vitaminology, 62, 185-191.
- Wang, Y., Hodge, A. M., Wluka, A. E., English, D. R., Giles, G. G., O’Sullivan, G., & Cicuttini, F. M. (2007). Effect of antioxidants on knee cartilage and bone in healthy, middle-aged subjects: A cross-sectional study. Arthritis Research & Therapy, 9, R66. https://doi.org/10.1186/ar2225
