Consideration of the applicability of alternative methods to animal experiment for health functional foods

The utilization of alternative methods to animal experiment in the evaluation of health functional foods has gained significant attention due to increasing ethical considerations and advancements in technology. Health functional foods are defined as products manufactured using ingredients or substances with beneficial effects on human health, aimed at supplementing nutrition, enhancing physiological functions, or reducing disease risk. This review the current status and applicability of alternative testing methods in this field, focusing on key health aspects such as skin, eye, and gut health. Skin health evaluations using in vitro models like reconstructed human epidermis and barrier membrane tests (e.g., Corrositex) are discussed, highlighting their effectiveness in replicating human skin responses. For eye health, in vitro and ex vivo models, including immortalized retinal pigment epithelium cell lines and corneal tissue cultures, provide promising alternatives to traditional animal testing. Gut health assessments utilize in vitro models like Caco-2 cell cultures and ex vivo techniques such as Ussing chambers to study nutrient absorption and barrier function. Despite these advancements, several challenges persist. Thecomplexity of biological interactions, limitations in standardization, and the need for comprehensive validation data remain significant barriers. Additionally, specific functional evaluations and the assessment of multi-component products pose difficulties in accurately replicating in vivo conditions. This review underscores the necessity for ongoing research, regulatory support, and the development of robust, standardized alternative methods to advance the ethical and scientific evaluation of health functional foods.