Plastics released into the environment can be degraded by physical erosion, biodegradation, photocatalytic activity, and oxidation, resulting in smaller plastics particles. Microplastics (MPs) are plastic particles relatively smaller than 5 mm in size. Furthermore, microplastics with particle sizes less than 1000 or 100 nm are known as nano-plastics (NPs). The presence and effect of MPs and NPs in human body has not been adequately studies, thus we aim to explain the origins of MPs and NPs adept, carefully explore the pathways by which MPs and NPs enter the body system and highlight the impact of MPs and NPs on human health. Major examples include Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyamide (PA), polystyrene (PS), polyethylene terephthalate (PET), Acrylonitrile-Butadiene-Styrene (ABS), and polymethyl methacrylate (PMMA). MPs and NPs were found to have two sources (primary and secondary). The primary sources are materials purposely produced to suit household and industrial uses, such as exfoliants for skin care products, construction, and packaging materials. Secondary sources originated from the decomposition/degradation of large plastic products over time. Plastics were found in plants (fruits and vegetables), animals (fish, crab, shrimp, oysters, and mussels), water (taps, sachet, and bottled water), salt, sugar, and honey. Plastics' impact on the human ecosystem is getting increasingly severe, and it is imperative that proper attention be paid to this issue. The vast number of MPs and NPs available can influence the lives of the populace in each geographic area. In this review article, we identified three routes through which MPs and NPs gain entrance into the human body: oral ingestion, cutaneous (skin contact), and inhalation. Furthermore, we investigated and summarized the impacts of MPs and NPs on human health. The most impacted organs in the body included the lungs, blood, kidney, brain, ovary, testes, and intestines. In this review, we offered a viable solution that includes the use of biodegradable polymers, increased usage of eco-friendly biotechnology and engineering solutions, and the implementation of regulatory measures. In future, we intend to investigate the bioaccumulation and effect of MPs/NPs on human health.