Microplastics are pervasive, with over 6 billion tons of plastic produced globally, and plastic waste is expected to triple by 2060. These tiny plastic particles, less than 5 mm in diameter (microplastics) and less than 1 micrometer (nanoplastics), enter the human body through ingestion, inhalation, or skin contact. They are found in the environment, including oceans, air, and food. Microplastics can come from intentional sources like microbeads in cosmetics or from the breakdown of larger plastics. Studies show microplastics are present in human tissues, including blood, lungs, placenta, and breast milk. Research indicates a potential link between microplastics in blood vessels and cardiovascular disease. In a study of 304 people, plastic was found in atherosclerotic plaques in about half of the participants, with microplastics associated with a higher risk of cardiovascular events. Another study found microplastics in human feces, with higher levels in people with inflammatory bowel disease. While these studies do not prove causation, they highlight the need for more research on microplastic exposure, including how much is absorbed, how they accumulate in tissues, and how their chemical and physical properties affect health. Mechanistic studies are needed to understand how microplastics cause damage, including through the immune system or microbiome. Environmental, social, and economic factors may also influence health impacts. International efforts are underway to manage plastic production and disposal. The EU has restricted microplastics in products and aims to reduce pollution by 30% by 2030. The UN Environment Assembly has adopted a resolution to develop a global plastics treaty by 2024. As understanding of microplastic health risks grows, more research and policy action are needed to reduce plastic's global impact and improve public and planetary health.Microplastics are pervasive, with over 6 billion tons of plastic produced globally, and plastic waste is expected to triple by 2060. These tiny plastic particles, less than 5 mm in diameter (microplastics) and less than 1 micrometer (nanoplastics), enter the human body through ingestion, inhalation, or skin contact. They are found in the environment, including oceans, air, and food. Microplastics can come from intentional sources like microbeads in cosmetics or from the breakdown of larger plastics. Studies show microplastics are present in human tissues, including blood, lungs, placenta, and breast milk. Research indicates a potential link between microplastics in blood vessels and cardiovascular disease. In a study of 304 people, plastic was found in atherosclerotic plaques in about half of the participants, with microplastics associated with a higher risk of cardiovascular events. Another study found microplastics in human feces, with higher levels in people with inflammatory bowel disease. While these studies do not prove causation, they highlight the need for more research on microplastic exposure, including how much is absorbed, how they accumulate in tissues, and how their chemical and physical properties affect health. Mechanistic studies are needed to understand how microplastics cause damage, including through the immune system or microbiome. Environmental, social, and economic factors may also influence health impacts. International efforts are underway to manage plastic production and disposal. The EU has restricted microplastics in products and aims to reduce pollution by 30% by 2030. The UN Environment Assembly has adopted a resolution to develop a global plastics treaty by 2024. As understanding of microplastic health risks grows, more research and policy action are needed to reduce plastic's global impact and improve public and planetary health.