Transient ischemic attack (TIA) is a well-established risk factor for future strokes, making interventions that target recovery and vascular risk crucial. This study aimed to assess the safety and clinical effects of a polyphenol-rich Salicornia ramosissima extract in post-TIA patients. A randomized, triple-blind, placebo-controlled trial was conducted with participants who had a history of TIA or minor stroke and who received 1 g of Salicornia extract or placebo over 11 months. Biochemical analyses, neuropsychological assessments (MOCA test), and gait and aerobic performance tests were conducted at the beginning and the end of the study. A total of 118 individuals were screened, with 80 finally included. Importantly, no significant adverse events were reported throughout the study. A neurological analysis showed an improvement in MOCA scores in patients treated with the Salicornia extract for 11 months. The treatment did not affect spatiotemporal gait parameters, but it significantly reduced blood pressure at baseline and after the aerobic performance test. Biochemically, both groups exhibited mild hyperhomocysteinemia at baseline; however, Salicornia treatment significantly lowered homocysteine levels, bringing them within the normal range. These findings highlight the safety of the Salicornia extract in patients at a high cerebrovascular risk and suggest it as a potential therapeutic option for managing vascular risk factors, such as hyperhomocysteinemia and hypertension. However, further studies are required to confirm the underlying mechanisms and explore broader clinical applications.