10 Beauty Benefits and Uses of Castor Oil Published on Feb. 26, 2017 in 10 Beauty Benefits and Uses of Castor OilFull resolution (628 × 394) ← Previous Next → Why It Works: Castor oil can moisturize your brows, eventually giving you a thicker, fuller shape, if applied daily before bed. How It Works: Simply massage a little into the brows using either clean fingers or a cotton-tipped applicator.