Castor oil has been used medicinally across multiple cultures for thousands of years — in ancient Egypt, India, China, and the Mediterranean. Its applications range from internal laxative use to external wound care and hair growth promotion, and it has maintained genuine clinical relevance into modern naturopathic practice. Barbara O'Neill discusses castor oil packs specifically as one of her most recommended therapeutic applications.
What Castor Oil Is
Castor oil is pressed from the seeds of Ricinus communis. It is unusual among plant oils in its fatty acid composition — approximately 90% of its fatty acid content is ricinoleic acid, a rare hydroxylated fatty acid not found in significant amounts in any other vegetable oil. Ricinoleic acid is responsible for most of castor oil's documented therapeutic properties.
Castor Oil Packs: Barbara O'Neill's Recommendation
O'Neill is a consistent advocate for castor oil packs — castor oil applied to a cloth and placed over the abdomen or other treatment area, often with gentle heat applied on top. She describes castor oil packs as supporting liver detoxification, reducing inflammation in the underlying tissue, and promoting lymphatic circulation in the area covered.
The scientific evidence for transdermal penetration of ricinoleic acid from castor oil packs is debated, but research by Dr. William McGarey documented measurable increases in lymphocyte production and immune function in patients using regular castor oil packs, suggesting a genuine immunomodulatory effect beyond simple skin moisturizing.
Castor Oil for Skin Directly
Applied directly to skin, castor oil's ricinoleic acid has documented anti-inflammatory and antimicrobial properties. Research has found castor oil effective for acne, seborrheic dermatitis, and as a carrier oil that enhances penetration of other topical compounds applied simultaneously.
The thick, viscous nature of castor oil makes it unsuitable as a standalone moisturizer for most people, but at 5 to 10% in a blend with lighter oils, it provides the ricinoleic acid benefit without the heaviness. In soap, as noted in our saponification content, castor oil's castoroate improves lather quality and contributes therapeutic ricinoleic acid to the formula.
Castor Oil for Hair and Scalp
Castor oil is widely used for hair growth promotion, scalp health, and eyebrow and eyelash thickness. The mechanism is not fully established but proposed to involve ricinoleic acid's anti-inflammatory effects on hair follicles and its ability to improve scalp circulation. Anecdotal evidence for hair growth effects is extensive; controlled clinical trials are limited but supportive in small studies.
For scalp conditions — seborrheic dermatitis, dry scalp, dandruff — castor oil's antimicrobial and anti-inflammatory properties are directly relevant. Our Pine Tar Rugged Bar Soap used on the scalp addresses many of the same conditions through a different mechanism, and some practitioners combine both — pine tar soap wash for antibacterial and anti-inflammatory cleaning, castor oil applied between washes for follicular support.
Beyond Clean, Beyond Ordinary.