Hair School Lesson 2: Moisturisers and Sealants

So what's the difference between a moisturiser and a sealant?

Moisturiser

A moisturiser penetrates the hair, and fills it with goodness. You hair feels soft and plump - not dry and brittle. You can have too much goodness, however. An over-moisturised hair will feel soft, gummy, and too elastic! If this happens to you, you need to balance your moisture with some protein. 

The main moisturiser for hair is cheap - it's water. Some oils also penetrate the hair shaft. Coconut and palm oil are the two big ones, but avocado oil and olive oil have some penetrating properties as well. These oils are great to utilise when you're suffering from hygral fatigue. When the hair is constantly swelling up with water, then slimming down as it dries out, the “swelling properties” (elasticity) of the hair gets “tired out”, sort of like a worn out rubber band. The hair becomes inelastic and may break. Applying penetrating oils – but not overdoing it – keeps your moisture levels more constant.

Sealant

Sealants coat the hair and create a barrier. This prevents the moisture in the hair from drying out as quickly. Sealants are also great for preventing hygral fatigue! A word of caution – applying copious amounts of sealants but not washing them out properly can cause build up which, in the long run, may lead to these sealants locking moisture out of the hair instead.

Silicones are artificial sealants, and are very commonly found in conditioners and other commercial products. Oils can also act as sealants. Many oils are non-penetrating, and therefore only coat the hair shaft. My personal non-penetrating favourites are sunflower oil and mineral oil since they’re light and easily available. Many people also like jojoba oil, shea butter, rapeseed oil, and castor oil.

Moisturiser/sealant combo

A nifty thing about penetrating oils is that if you apply only a small amount it will penetrate into your hair, but if you apply a little more, the excess amount will coat your hair as a sealant! The amount used is highly individual and depends on how porous your hair is – i.e. how well it absorbs moisture. Curly hair, dyed hair, dry hair, and damaged hair tend to be very porous and soak up moisture like a sponge. The moisture also leaves the hair quickly, if sealants aren't used. But this is not a certain fact; my hair is dry and non-porous, for example.