Rooibos <i>Aspalathus linearis</i> – Can it reduce the incidence and severity of acute mountain sickness? A case study of Aconcagua (6962 m) climbing expedition, Argentina

Abstract

Sport and leisure activities at altitude, including climbing, trekking and various snow sports, continue to grow in popularity. However, the increase of high altitude activities is associated with hypoxia and its consequences, namely acute mountain sickness (AMS), which can manifest in two life-threatening conditions, namely high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE). The most common methods for dealing with the potential onset of AMS involve acclimatization strategies, such as ascending 500m or less a day, and ingesting prescribed prophylactic medication, which can have adverse side effects. The study focuses on the efficacy of the fynbos plant rooibos Aspalathus linearis to reduce and/or prevent AMS. Rooibos is a unique South African herbal product usually consumed as a tea and a dietary source of unique bio-active antioxidants. A case study was conducted involving eight climbers (mean age: 46.6± 11.2 years) who supplemented their diet with rooibos in capsule form containing ~ 400mg rooibos extract (standardized to include 130mg total polyphenols/capsule) taken 3 times per day during the ascent of Aconcagua (6962 m) in Argentina. The dosage is equivalent to about 6 cups of rooibos tea per day. Daily resting mean heart rate increased from 62 to 87 beats per minutes (bpm) and mean peripheral blood oxygen saturations levels declined from 98% to 79% SpO₂. The Lake Louise (LLS) assessment reported negligible symptoms of AMS for seven climbers up to, and at 6000 m. It is tentatively asserted that the findings indicate the potential of the rooibos plant Aspalathus linearis to reduce the symptoms and/or onset of AMS for those persons ascending to high altitudes, whether for sport, leisure or for work.

Keywords: Hypoxia, acute mountain sickness (AMS), Rooibos.