Using hair oils well: dose, timing and wash-out

Hair oil does not make hair greasy. The amount you use and the way you wash it out do. Almost every bad experience with oils comes down to one of four things, and all four are easy to fix.

1. Put it on dry hair

Not damp, not wet. Water sits between the oil and the surface you are trying to reach. On the scalp it also turns a dropper line into a puddle. Damp application is the most common mistake in this category.

2. Use less than you think

No 01 Scalp Serum: one to two millilitres, which is one to two full droppers, along the partings.
No 02 Pre-Wash Hair Oil: roughly two to four millilitres for shoulder-length hair.

That is a small pool in the palm, not a handful. Overdosing is the single most common reason people say oils made their hair greasy.

3. Give it enough time

• Under 30 minutes: surface conditioning only. Better than nothing, but not what these oils are designed for.
• 2 hours: the minimum. Enough contact time to do its job.
• Overnight: the best result. Use a silk or satin pillowcase, or wrap your hair.

Longer than overnight adds nothing except more washing.

4. Do not overdo the frequency

One to two times a week is enough for No 01 and No 02. More is not better. It is just more washing.

Washing it out

Oil and water do not mix. If you wet your hair first, you dilute the shampoo before it reaches the oil, and you end up shampooing three times.

1. Do not wet your hair first.
2. Put shampoo straight onto the dry, oiled hair and work it through until it turns milky. The milkiness is the oil lifting.
3. Only then add water and lather.
4. Rinse. A second short shampoo is normal after a generous application, especially on fine hair.

Why oil before the wash

Hair swells when it absorbs water and contracts as it dries. Repeated thousands of times over years of washing, this lifts and cracks the outer layer of the hair. It is called hygral fatigue. The idea behind oiling before you wash is that an oil that gets into the hair takes up space that water would otherwise fill.

The classic reference is a 2003 study in the Journal of Cosmetic Science (Rele and Mohile). It compared mineral oil, sunflower oil and coconut oil for how well they prevented protein loss from hair. Coconut oil reduced protein loss in both damaged and undamaged hair. The other two did not. It is a study of those oils, not of any product from this brand.

Scalp or lengths?

Your scalp is skin and your hair is fibre. They need different things. No 01 Scalp Serum is for the scalp. No 02 Pre-Wash Hair Oil is for the lengths. Most people use both in the same session, on different parts of the head.

Good to know

• Patch test first: behind the ear or inside the elbow, 24 hours, before your first full use.
• A cool tingle from No 01 is the peppermint and is normal. Burning, stinging or redness is not: wash it out and stop.
• If you have a diagnosed scalp condition, broken skin or hair loss you are worried about, please see a dermatologist before using any oil.
• No 01 and No 02 contain sweet almond oil, and No 02 also contains coconut oil. If you have a nut allergy, please speak to your doctor first.

Read next: Using essential oils safely.