Hair Serums & Oils: What Actually Works
Hair serums and oils are some of the most misunderstood products in a haircare routine — overused, under-used, or filled with ingredients that quietly undo everything else you're doing. Here's what to look for, what to avoid, and how to actually use them.
THE GOOD STUFF — Ingredients That Actually Nourish
Not all oils behave the same way. Some penetrate the cortex of the hair shaft and genuinely condition from within. Others form a protective film on the outside. Both have value — the key is knowing what you're working with.
Penetrating Oils
Argan oil — Rich in oleic and linoleic acids. Penetrates the hair shaft, reduces protein loss, and adds shine without grease.
Marula oil — High in oleic acid and absorbs quickly. Ideal for dry or coarse textures and frizz control without buildup.
Avocado oil — Penetrates and moisturizes deep into the shaft. Great for thick, curly, or chemically treated hair.
Protective & Sealing Oils
Jojoba oil — Technically a liquid wax that mimics sebum. Seals the cuticle, balances scalp oil production, and is non-comedogenic.
Sweet almond oil — Lightweight and sealing, rich in vitamin E. Works beautifully in leave-in serums for fine hair.
Sea buckthorn — Packed with omega-7 and carotenoids. Supports a healthy scalp environment and is a staple in biodynamic formulas like Oway.
Rosehip oil — High in vitamins A and C. Helps with scalp inflammation and nourishes both hair and the skin at the hairline.
A note on biodynamic oils: The soil these botanicals are grown in matters. Biodynamic farming — the practice behind Oway's entire line — produces higher concentrations of active compounds, meaning the oil is more potent at the same volume. It's not marketing language. It's measurable.
WHAT TO AVOID — Ingredients That Cause Harm
Many mainstream serums use synthetic ingredients to create the illusion of smooth, shiny hair while causing long-term damage. Here's what to flip the bottle over and look for.
Avoid Entirely
Dimethicone & silicones — Create an impermeable coat that traps dryness in over time. Buildup disrupts moisture balance and requires harsh sulfates to remove.
Mineral oil / petrolatum — Derived from petroleum. Sits on top of hair, blocking moisture absorption and contributing to buildup with no actual nourishment.
Synthetic fragrance — Often a cocktail of undisclosed chemicals including endocrine disruptors. Absorbed through the scalp and linked to sensitization over time.
Parabens — Preservatives that mimic estrogen in the body. Shown to penetrate skin and accumulate in tissue — unnecessary when clean alternatives exist.
Use With Caution
Castor oil (undiluted) — Too thick to use alone. Can clog follicles if applied directly to the scalp. Always blend with a lighter carrier oil first.
Essential oils (undiluted) — Potent and bioactive. Even beneficial oils like tea tree or rosemary can cause scalp irritation at full concentration.
Certain alcohols — Short-chain alcohols (isopropyl, SD alcohol) strip moisture. Fatty alcohols like cetyl or stearyl alcohol are fine — they're actually conditioning agents.
HOW TO ACTUALLY USE THEM — Application Guide
The most common mistake with hair oils isn't the product — it's the placement, the timing, or the amount. Here's how to apply serums and oils so they perform the way they're meant to.
1. Start with the right hair state. Oils work best on damp or dry hair, not soaking wet. Towel-blotted damp hair absorbs product most effectively. Applying to dripping wet hair dilutes the formula and sends most of it straight down the drain.
2. Less than you think. For fine to medium hair, start with 2–3 drops of oil or a pea-size amount of serum. You can always add more. Oily roots from over-application take a full wash cycle to correct.
3. Emulsify in your palms first. Rub the product between your hands for 3–5 seconds to warm it before touching your hair. This improves spreadability and prevents uneven patches of concentration.
4. Mid-shaft to ends only — unless specified. The scalp produces its own oil. Unless you're doing a dedicated scalp treatment, keep serums away from the roots. Focus on the driest areas: ends and around the face frame.
5. Know your porosity. High-porosity hair (chemically treated, heat-damaged, naturally coily) absorbs quickly and benefits from rich, penetrating oils. Low-porosity hair repels moisture — lightweight oils like jojoba or sweet almond are better fits to avoid buildup.
6. Time it right for heat styling. If you're blow-drying or flat ironing, apply a heat-protective serum after towel-drying but before any heat. Avoid applying pure oils immediately before high heat — some oils can reach their smoke point and cause protein damage.
Pro tip — Pre-wash oil treatment: Apply oil to dry hair 30–60 minutes before shampooing. This creates a protective barrier that keeps shampoo from stripping too aggressively. Coconut oil excels here. Especially useful for color-treated or naturally dry hair.
CLOSING / CTA:
Not sure which oil or serum is right for your hair type? Our team uses biodynamic Oway formulas chosen for your specific texture, porosity, and goals. Book a consultation at Phieco and we'll dial it in.