Where Does Rosemary Have the Strongest Evidence?

Rosemary has been investigated in several areas of human health, but the clinical evidence is still developing.

One particularly interesting area is cognition, mood and fatigue. A controlled study in healthy working-age adults found that regular intake of rosemary extract improved some measures of mood, fatigue and cognitive performance. Other human studies have also explored rosemary extracts for stress-related effects and cognitive function.

Rosemary has also been studied in inflammatory conditions. A clinical trial using rosemary leaf powder in people with rheumatoid arthritis reported improvements in some symptoms and markers associated with inflammation and oxidative stress, although more research is needed.

Research on rosemary essential oil has followed a somewhat different path. Inhalation studies have investigated its effects on alertness and drowsiness. For example, research involving night-shift workers found that inhaling rosemary oil reduced drowsiness and increased alertness.

Topical rosemary preparations have also been studied for pain and musculoskeletal complaints, including osteoarthritis. Results are promising, but many of these studies are relatively small and specific to particular preparations and populations.