Hands up if you want glossy, healthy and smooth hair? That’s most of us then. Sadly, unruly frizzy hair is the barrier between the hair we want and the hair we have. There are many reasons why your hair might not be co-operating: perpetually dry hair, breakages, split ends and static all contribute to a halo of fuzz.
Why does hair frizz?
Hair frizz can be caused by a few environmental factors, namely:
1. Humidity: Hair is made up of three layers- the cuticle, the cortex, and the medulla, and thousands of cells. The outer most layer, the Cuticle, consists of cells arranged like the tiles of a roof, overlapping one over the other. The primary purpose of the cuticle is to protect the hair’s middle layer i.e the cortex, which should ideally lie flat. When the overlapping cells of the cuticle are slightly raised, moisture can seep into the inner cortex causing it to swell. Healthy hair normally holds around 15% of water weight, which can increase to 30% in very humid conditions. However, damaged hair can absorb over 50% of its weight of water from a humid environment, which can cause severe frizziness, which is incredibly hard to manage.
2. Friction: Hair can also get frizzy because of static electricity. When hair is combed or brushed, the hair shaft develops a weak negative charge on all strands. As they have a similar charge, strands of hair begin to repel each other instead of staying in place, much like magnets that repel each other.
3. Other environmental factors that promote a loss of hair lipids or an increase in moisture also promote frizz. These include hot showers (which strip hair of natural lipids/oils), excessive sun exposure and chlorine in swimming pools can all lead to dry, frizzy hair.
Certain hair types are more prone to frizz than others. These include:
1. Dry Hair: Our hair is primarily composed of lipids, water, and the hair protein keratin. Together, all three are important for hair strength and structure, and alterations in any one of these can affect hair quality. Lipids provide a protective barrier to moisture, preventing excessive moisture from entering the hair cortex. People with dry hair normally have lower levels of lipids in their hair, compromising this protective effect. When it’s humid outside, dry hair soaks up the excess moisture in the air, which causes swelling of the cortex and changes interactions between strands of keratin.
2. Damaged Hair: Chemical and physical damage to hair can make it more prone to frizz. Chemical damage is the kind that normally takes place due to treatments such as colouring, permanent waves, and overuse of shampoos and alcohol-based gels. Physical damage occurs when hair is stretched beyond its capacity. Hair can stretch up to 30% without experiencing any damage. However, stretching it between 30%-70% can lead to damage, with stretching over 80% leading to breakages Vigorous brushing of wet hair, ironing and even types of styling can stretch hair beyond 30%, causing damage. Damaged hair is more porous, causing more water absorption (and swelling), making it prone to frizz. In fact, a study reported that 67% of complaints after chemical straightening were frizzy hair! 
Managing frizzy hair
Keeping track of both external and internal factors is important to ensure hair health.
External factors can be controlled by reducing or stopping damaging chemical treatments and physical damage, as well as limiting the use of heat based tools for styling.
Choosing the right shampoo, conditioner and hair serum can also help significantly. Most shampoos available in the market contain positively charged surfactants (soap molecules) like ammonium lauryl sulfate, sodium laureth sulphate. While these are very good at removing sebum and dirt, they also remove natural oils and lipids which lead to dry hair. Moderating use of shampoos and looking for negatively charged ingredients like trimethylalkylammonium chlorides can help manage frizz.
Conditioners can help reduce frizz by neutralizing the negative charge on hair. Looking for products with hydrating ingredients can help address damage as well, by lubricating the hair shaft.  Look for a conditioner that contains glycerin as well as other hydrating ingredients (like coconut oil and shea butter). Using an after-wash serum can also help protect hair from environmental moisture.
Beat frizz from within:
Healthy hair is less vulnerable to the factors that can cause frizz and a nutrient-rich diet can strengthen hair internally to protect against external factors. Extreme diets that restrict calories or insufficient quantities of essential nutrients, such as proteins, minerals, essential fatty acids, and vitamins cause damage to hair which can further lead to structural abnormalities, greying, or hair loss. 
Nutrients that support healthy hair include:
1. Omega-3 fatty acids (from fish, walnuts and chia seeds) and gamma-linolenic acid (from evening primrose oil and borage oil) contribute to lipids in the hair which ultimately translates to less frizz.
2. Sulphur-containing amino acids (taurine, cysteine and methionine) are the building blocks of keratin, our hair’s main protein. Soya foods contain the highest amount of cysteine. Good amount of cysteine can also be found in chia seeds, flax seeds, and oats.
3. B vitamins like niacin (vitamin B3), biotin (vitamin B7), folic acid (vitamin B9) and cobalamin (vitamin B12) are involved in the hair-building process and support the metabolism of the rapidly diving cells that construct hair structures.
Balanced nutrition and limiting exposure to damage from physical and chemical sources can keep hair healthy enough to fight frizz of its own accord, with results lasting much longer than temporary solutions such as conditioners.
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