Hair and Cold Water

Woman washing her hair with cold water
Photo: Pixelshot/Canva
Q: Is it true that ice-cold water is good for your hair? What is the effect of very cold water on your hair? What are the potential benefits?
A: When it comes to hair care, we often focus on hair products and special treatments, but there is a simple and literally refreshing method that is inexpensive and easily accessible to everyone: ice-cold water. The idea of rinsing your hair with very cold water may seem intimidating at first, but the benefits it brings to the health and appearance of your hair make it worth trying.
Hair has three layers: the cuticle, the cortex, and the medulla. The outer layer, the cuticle, looks like shingles when viewed under a microscope and plays a crucial role in protecting the inner layers of the hair and determining overall health, strength, and appearance. Warm water opens this outer layer.
Usually, warm water is preferred when washing the hair. It helps open the outer layer, allowing better penetration of cleansers and other hair products. Unfortunately, opening this layer also makes the hair more porous and susceptible to damage. Cold water, on the other hand, helps to close this outer layer. And this is where the benefits of using cold water come into play.
More shine and smoothness: One of the main benefits of using ice-cold water on your hair is the improvement of shine and smoothness. As cold water closes the outer layer, the hair surface becomes smoother. Light reflects more evenly from the smooth hair surface, resulting in shine. This leads to hair that is not only visibly shinier but also feels softer.
Less frizz: The theory behind using very cold water to combat frizz lies again in the ability to close the outer layer of the hair and reduce the chance of unruly individual hairs. The result is smoother and therefore less frizzy and more manageable hair. This can be very beneficial for people with curly hair prone to frizz.
Stronger hair and more resilience: Cold water can contribute to the strength and resilience of your hair. The closed cuticle provides a protective layer, reducing the risk of damage from external factors such as pollution, UV rays, and styling tools. It will also reduce the potential damaging friction between hair strands. Stronger, more resilient hair is less prone to breakage and split ends.
Reduction of heat damage: Heat styling tools such as hairdryers, straighteners, and curling irons can strip the hair of its natural moisture and make it susceptible to damage. Rinsing your hair with very cold water helps to close the cuticle layer, retain moisture, maintain optimal humidity levels, and reduce the impact of heat damage.
Better blood circulation: The sensation of ice-cold water on your scalp can lead to improved blood circulation. When you expose your scalp to cold water, blood vessels constrict and then dilate as your scalp warms up, promoting blood flow. Improved blood flow means better supply of oxygen and nutrients to the hair follicles, which can contribute to potentially healthier hair and better hair growth.
While the benefits of using ice-cold water on your hair are clear, it is essential to approach this with caution. Ice-cold water can be uncomfortable or irritating for people with a sensitive scalp. It's important to listen to your body and adjust the water temperature accordingly. Everyone's hair reacts differently, and it's necessary to monitor how your hair responds to the cold water.
Alternating between warm and cold water in your hair care routine can offer the best of both worlds. Starting with a wash with warm water to open the cuticle layer and clean the hair, followed by a rinse with cold water to close the cuticle, can be the perfect balance for most people. Experiment to find the right balance!
See also: Does hair absorb water?