A red vine leaf extract reduces leg swelling in healthy women in a placebo-controlled clinical trial

In the present study, we investigated whether oral intake of a hydroalcoholic extract from red vine leaf (Vitis vinif. fol extra. s. sicc.) extract improves swelling of lower limbs in a single-blinded, placebo-controlled clinical study conducted in Japan using the crossover design. Seventeen healthy women, recurring suffering from swollen legs participated in the trial. Participants ingested 600 mg daily of the extract during 6 weeks, then matching placebo capsules for the same duration after a wash-out period of 2 months. Limb volume was determined by water displacement volumetry at the beginning and at the end of the study. For this purpose, the leg volumes were measured twice a day, in the morning and in the evening of the assessment day. Changes in volume were calculated by substracting the leg volume in the morning from the leg volume in the evening. Additional assessments included complete blood analysis and vital signs to monitor for safety of the treatment.

Swelling of the right leg decreased significantly after 6 weeks of red vine leaf treatment compared to placebo (p = 0.018). In addition, the volume measured at the left leg after 6 weeks of extract treatment was significantly reduced compared to study start, both in the morning and evening, although no significant change in the swelling of the left leg could be detected compared to placebo. In summary, these findings indicate that the red vine leaf extract tested in this trial was able to reduce lower limb swelling in otherwise healthy women, and has therefore oedema-preventing properties that might be helpful to alleviate symptoms of venous insufficiency.