Hemp Seed Oil

Overview

Hemp seed oil is pressed from the seeds of Cannabis sativa, the industrial hemp plant. It is not CBD oil — CBD oil is extracted from the flowers and leaves and has a totally different chemistry. Hemp seed oil contains negligible CBD and no THC. It is a culinary and cosmetic oil widely sold in health-food stores and DIY suppliers.

Cold-pressed hemp seed oil is a striking dark green — sometimes almost emerald — with a grassy, slightly nutty smell. Refined hemp oil is pale yellow with very little scent. Cold-pressed is what most DIYers want for skincare, despite the color carry-through, because the natural antioxidants and feel are better preserved.

Shelf life is short — typically 6-12 months stored cool and dark, often less. Refrigeration is strongly recommended after opening.

What it does in a formula

Hemp seed oil is roughly 50-60% linoleic acid, 15-25% alpha-linolenic acid, 3-5% gamma-linolenic acid (GLA), with about 10-15% oleic and small amounts of saturated fats. The triple PUFA load (linoleic + alpha-linolenic + GLA) is unusual and is why hemp oil is so prized for irritated, mature, and barrier-compromised skin. The omega-3:omega-6 ratio in hemp is famously close to the proportions the human body uses.

On skin it absorbs at a medium-fast pace, leaving a faint conditioning film. The slight green tint can carry through to finished products at higher percentages.

How to use

Add at cool-down, below 40 C. The high PUFA content means hemp degrades quickly under heat. Always add 0.5-1% tocopherol (vitamin E) to any hemp-containing product. Refrigerate the original bottle once opened.

Usage rates by product type:

• Face serums and face oils: 10-50% (often blended with more stable carriers like jojoba)
• Face creams and lotions: 3-10%
• Body lotions: 5-15%
• Hair masks and scalp oils: 5-20%
• Cold-process soap: 3-10% (SAP value approximately 0.135 NaOH; needs balancing oils)

Best for / Worst for

Best for: dry, mature, inflamed, or eczema-prone skin, scalp treatments, beard oils, after-sun lotions, any formula building around omega-3 supplementation, hair masks for dry damaged hair.

Worst for: long-shelf-life products without cold storage, white or pastel-colored products (the green carries through), strict scent-free formulas (the grassy note is real), oily skin used at high percentages.

Common pitfalls

Rancidity. Hemp oil goes off fast. The smell turns sharp, fishy, or paint-like when it has oxidized. Bought a 500 ml bottle “for value”? You will likely have to throw half of it out. Buy small (100-250 ml), keep it refrigerated, and use within 4-6 months of opening.

Heating it. Holding hemp oil at 75 C for 20 minutes in the oil phase visibly degrades it — the color darkens and the smell intensifies. Always cool-down add.

Confusing it with CBD. Hemp seed oil is a culinary-grade carrier oil. CBD oil is a flower/leaf extract dissolved in a carrier. They are not interchangeable, and CBD oil is regulated very differently. Always check the INCI: Cannabis Sativa Seed Oil. Reputable suppliers explicitly confirm “this oil is extracted from seeds so it does not contain cannabinoids” on the product page — useful language to look for, especially in markets where hemp regulations are still strict.

Color staining. A 15% hemp oil cream can come out distinctly green-tinted. Not a flaw, but expect it. Use refined hemp or reduce the percentage if you need a pale product.

Low oleic content. Hemp’s oleic acid is only ~12%, so combining it with oleic-rich oils like olive or avocado helps round out the fatty acid profile and improve cushion on dry skin.

Substitutes

• Rosehip oil — similar PUFA-rich, similar instability, similar barrier-support reputation, no green color.
• Sunflower oil (high-linoleic) — much cheaper, more linoleic-leaning, lower omega-3. Suitable for barrier support at scale.
• Black currant seed oil — similar GLA content, more shelf-stable, more expensive.
• Borage and evening primrose oil — high in GLA, similar fragility, often used together with hemp for layered support.