Rosemary has many potential health benefits, including:
Digestive health: Rosemary may improve the digestive system. 
Food preservative: Rosemary's antioxidant and anti-microbial activities may prevent microbial growth and decrease food spoilage. 
Circulatory system: Rosemary may improve blood circulation. 
Nervous system: Rosemary may support the nervous system. 
Brain health: Rosemary may help improve memory, concentration, and cognitive processes. Inhaling rosemary oil may reduce the risk of neurological conditions like Alzheimer's disease. 
Blood sugar: Rosemary tea may help lower blood sugar levels. 
Immune system: Rosemary's antioxidants and anti-inflammatory compounds may help boost the immune system. 
Skin health: Rosemary's anti-inflammatory, antibacterial, and anti-fungal properties may help promote healing for minor cuts, scrapes, insect bites, and rashes. 
Hair health: Rosemary may help preserve hair, decrease hair loss, and potentially stimulate hair growth. 
Rosemary is also a common spice in cooking, especially in Mediterranean dishes. It's also used for fragrance in soaps and cosmetics.