Hemp seed oil is a useful hair care ingredient, particularly for dry, damaged, or curly hair. The high linoleic acid content moisturises hair shafts, the modest weight does not weigh down fine hair, and the natural origin makes it appropriate for consumers avoiding silicones and synthetic conditioners.
How hemp seed oil interacts with hair
Hair is keratin, a protein structure that benefits from lipid coating for moisture retention and frizz control. The fatty acids in hemp seed oil coat the hair shaft, providing:
- Moisture retention by reducing trans-epidermal water loss
- Reduced friction (less mechanical damage during brushing)
- Improved shine through smoother light reflection
- Reduced frizz from better cuticle alignment
Hemp seed oil is light enough to penetrate the hair shaft to some degree, unlike heavier oils (coconut, castor) that primarily coat the surface.
Use cases by hair type
Curly and coily hair
Hemp seed oil works well as a leave-in moisturiser. The lightweight texture means it does not weigh down curls. Use on damp hair after washing, focusing on the lengths and ends. Approximately 1 to 2 teaspoons depending on hair length.
Straight and fine hair
Use sparingly to avoid weighing down fine hair. A few drops applied to the ends only is typically sufficient. For deeper conditioning, use as a pre-wash treatment that is washed out.
Dry or damaged hair
Pre-wash treatment is the most effective approach. Apply 1 to 2 tablespoons of hemp seed oil to dry hair from mid-length to ends. Cover with a shower cap or towel. Leave 30 minutes to overnight. Shampoo out.
Oily scalp
Apply only to lengths and ends. Avoid the scalp, which already produces sebum. Use as a finishing oil rather than a treatment.
Specific applications
Pre-wash treatment (deep conditioning)
- Apply 1 to 3 tablespoons hemp seed oil to dry hair, focusing on lengths and ends.
- Cover with a shower cap.
- Leave 30 minutes to overnight.
- Wash with regular shampoo; may require two washes to fully remove.
Leave-in finishing oil
- Warm a few drops of hemp seed oil between palms.
- Apply to damp hair after washing, focusing on lengths and ends.
- Style as usual.
Scalp massage
- Warm 1 tablespoon hemp seed oil.
- Massage into scalp using fingertips for 5 to 10 minutes.
- Leave 30 minutes to 2 hours.
- Wash with regular shampoo.
Beard care
Hemp seed oil is a common ingredient in beard oils because of its light texture and skin compatibility. For DIY beard oil: combine 2 tablespoons hemp seed oil with 1 tablespoon jojoba oil and 10 drops of cedarwood or sandalwood essential oil. Massage a few drops into the beard daily.
What hemp seed oil does not do
- It does not stimulate hair growth in a clinically meaningful way; this claim is sometimes made without evidence.
- It does not prevent or reverse hair loss.
- It does not change hair colour or texture permanently.
- It does not protect hair from heat styling beyond a minor temperature buffer.
Storage for cosmetic use
The same storage rules apply as for culinary hemp seed oil: refrigerate, use within 60 to 90 days of opening, keep in dark glass. Rancid hemp oil applied to hair will smell unpleasant and may transfer that smell to clothing and pillows.