Essential oils could help on two fronts: The potent plant oils promote relaxation and may treat hair loss. A study published in the Archives of Dermatology found that a daily scalp massage using the oils boosted hair growth in 44% of patients. Try Avalon Organics Rosemary Volumizing Shampoo ($10.50; avalonorganics.com), which has rosemary essential oil. And stock up on oils at auracacia.com to mix your own blend based on the study’s recipe (below).  Your Fix for Full Hair1. Place 1/2 tsp jojoba oil and 4 tsp grapeseed oil (known as carrier oils) in a small bowl. 2. Mix in 2 drops of thyme oil, 3 drops of lavender, 3 drops of rosemary, and 2 drops of cedarwood. 3. Massage into scalp for 2 minutes every night; rinse in the morning. More from Prevention: Best Products For Full Hair