Background: Rasam is a traditional South Indian food, prepared using tamarind juice as a base, with a variety of spices. Rasam, with all its ingredients medicinally claimed for various ailments, is a functional food. Systematic consumption of traditional functional food provides an excellent preventive measure to ward off many diseases. Objective: To study rasam for cytotoxic, antimitotic, and antiproliferation potential beyond its culinary and nutritional effect. Materials and Methods: Brine shrimp lethality assay, onion root tip inhibition assay, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in Calu-6, HeLa, MCF-7 cell lines for four stage-wise samples in the preparation of rasam (RS1, RS2, RS3, and RS4) were studied. Results: RS4, the end product of rasam showed high lethality with an LC50value of 38.7 μ L/mL. It showed maximum antimitotic activity in a dose-dependent manner compared to other samples with an IC50value of 189.86 μ L/mL. RS4 also showed an IC50value of 350.22 and 410.15 μ L/mL in MCF-7 and Calu-6 cell lines, respectively. Conclusion: From this study, we suggest that rasam is a classic example of traditional functional food and it can treat breast and lung cancer on chronic use.