The length of time a person stays in ketosis with Pruvit can vary depending on several factors. Generally, when following a ketogenic diet and consuming Pruvit exogenous ketones, individuals can expect to remain in ketosis for a few hours to a few days. However, it's important to note that maintaining a state of ketosis requires consistent adherence to a low-carbohydrate, high-fat diet and regular consumption of Pruvit products.