Herbal and functional food phytochemicals in chronic disease: modulating oxidative stress and health outcomes.

Oxidative stress, described as an imbalance between the production of reactive oxygen species and antioxidant systems, has an important pathogenic role in many chronic diseases, such as cancer, cardiovascular disease, diabetes mellitus, stroke, and neurodegeneration. This narrative review investigates the effect of common herbal medicines and functional foods in oxidative stress, based on available experimental and clinical data. Curcuma longa, Emblica officinalis, Zingiber officinale, berries, and leafy vegetables, which contain bioactive molecules like polyphenols, flavonoids, and terpenoids, have been shown to have antioxidant and anti-inflammatory properties through activation of Nrf2 and NF-κB signalling pathways. The important findings from this review suggest that curcumin and gingerol possess anticancer properties via the regulation of p53, MAPK, and ROS-JNK pathways, which induce apoptosis in cancer cells. Moreover, these bioactive compounds improve mitochondrial dysfunction and redox status in cardiovascular diseases. Bacosides and withanolides can be used for neuroprotection by preventing oxidative injury and protein aggregation in neurodegenerative diseases. The antioxidant-rich herbs and functional foods may have promising roles in oxidative stress-related disorders as preventative and supportive treatment options; however, further research is needed to establish their efficacy and safety in patients.