The health benefits of Kiwi
A few days ago I saw golden kiwis in Whole Foods, and decided to try them. Oh my goodness, they were delicious!! I wanted to share the health benefits of Kiwi, they are so amazing for your gut!
Benefits-Kiwifruit contains vitamin C, carotenoids, polyphenols, and dietary fiber, and these are all potentially beneficial to the immune system. Research that has contributed to our understanding of the beneficial effects that kiwifruit may have on immune responses spans from in vitro studies using cell lines and human blood cells, to using animal models targeting both mucosal and systemic immunity. Some limited human intervention trials have been undertaken that demonstrated that kiwifruit can influence a number of biomarkers of oxidative stress and beneficial immune responses (Skinner, Bentley-Hewitt, Rosendale, Naoko, & Pernthaner, 2013).
Kiwi’s Vitamin E content can elicit positive effects in fighting free radicals, as well as high levels of polyphenols can exert positive immunostimulatory effects. According to research published in the Journal of Cellular Physiology, the polysaccharides in kiwifruit are able to double collagen synthesis in the body (Deters, Schroder, & Hensel, 2005). Both green and golden kiwifruit have shown antifungal and antibacterial capabilities in several studies, often found in the seeds (Basile et al., 1997). The protein in golden kiwifruit contains actinchinin, which is suggested as the source of its antifungal activity. Both the antibacterial and antifungal activity are considered part of its antioxidant profile.
The common green kiwifruit, Actinidia deliciosa, has been used as a ‘model’ fruit in several trials to examine effects on biomarkers relevant to both cancer and cardiovascular disease. A typical kiwi fruit has 85mg of vitamin C per 100g. “A kiwifruit extract has powerful antioxidant activity in vitro, and in humans, regular consumption of this fruit inhibits platelet aggregation, decreases endogenous oxidation of lymphocyte DNA, protects lymphocyte DNA from oxidation in vitro, and enhances the capacity of lymphocytes to repair DNA oxidation damage (Skinner et al., 2013). Comparison of the anti-oxidant effects in vitro demonstrated that kiwi fruit had stronger anti-oxidant effects than orange and grapefruit, which are rich in vitamin C. Interestingly, golden kiwi had the strongest anti-oxidant effects.
Another interesting feature of kiwifruit is that it may help increase the abundance of certain strains of bacteria such as F. prausnitzii are often associated with gastrointestinal disorders, and Akkermansia spp which uses this mucin as its source of energy. “The mechanisms by which F. prausnitzii facilitates its health promoting impact are most probably through butyrate production and subsequent anti-inflammatory effects” (Blatchford et al., 2017). Butyrate is the preferred energy source for colonic epithelial cells and plays a role in alleviating inflammation as well as mitigating cancer promotion, pathogenic colonization and oxidative stress. When mucin colonizes the intestine, it can protect the gut from pathogens by means of competitive exclusion (Ubiome, 2016). Mucin acts as an adhesive surface for numerous microbes, facilitating host-microbe interactions. Some data suggest there is a correlation with mucin and acetate (another SCFA) which can be involved in bodyweight regulation. A low concentration of Akkermansia spp. in the gut could indicate a thin mucous layer, thereby resulting in a compromised gut barrier function, and increased translocation of bacterial toxins. As a result, kiwifruit has been implicated in promoting several aspects of gut health including improving stool frequency, increasing commensal bacteria and improving aspects of immune function (Blatchford et al., 2017). Short chain fatty acids such as acetate, propionate and butyrate are also produced as a result of microbial fermentation of kiwifruit polyphenols.
Drug interactions- Kiwi might slow blood clotting and increase bleeding. In theory, kiwi might make bleeding disorders worse. High fiber diets may lower the efficacy of Simvastatin, Ezetimibe, pravastatin and fluvastatin (Bushra, Aslam & Khan, 2011).
Blatchford, P., Stoklosinski, H., Eady, S., Wallace, A., Butts, C., Gearry, R., . . . Ansell, J. (2017). Consumption of kiwifruit capsules increases Faecalibacterium prausnitzii abundance in functionally constipated individuals: a randomised controlled human trial. J Nutr Sci, 6, e52. doi:10.1017/jns.2017.52
Deters, A. M., Schroder, K. R., & Hensel, A. (2005). Kiwi fruit (Actinidia chinensis L.) polysaccharides exert stimulating effects on cell proliferation via enhanced growth factor receptors, energy production, and collagen synthesis of human keratinocytes, fibroblasts, and skin equivalents. J Cell Physiol, 202(3), 717-722. doi:10.1002/jcp.20161
Skinner, M. A., Bentley-Hewitt, K., Rosendale, D., Naoko, S., & Pernthaner, A. (2013). Effects of kiwifruit on innate and adaptive immunity and symptoms of upper respiratory tract infections. Adv Food Nutr Res, 68, 301-320. doi:10.1016/b978-0-12-394294-4.00017-1