Myth or fact: Does rinsing your hair with cold water really make it shinier?

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Blasting your head with freezing water at the end of a warm shower is about the last thing any sane person feels like doing in winter. Yet there are many of us who willingly undergo this water torture because we’ve been told it will bestow Kate Middleton-esque gloss upon our hair.

Whether you heard it from a magazine, your big sister, hairdresser, or Miranda Kerr (who says it makes her hair “really shiny”, the ‘cold rinse = glossy hair’ belief has been around for a long, long time.

The theory goes something like this: warm water opens the hair cuticle — the outermost layer of each strand — making it appear more dull. Blasting it with cold water supposedly ‘seals’ the cuticle, making your strands appear smoother and shinier.

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On paper it sounds kind of legit… but does that make it true? Well, not necessarily.

Dr Tim Moore, Chief Technical Officer at ghd’s Research and Development Facility, told The Glow his team has explored this popular myth, but to date they haven’t found any solid, scientific proof it works. (Post continues after gallery.)

“People say a lot of things in the hair styling and beauty industries and some of it is spot on… so we looked at it and said, ‘Does this have any real scientific benefit behind it?'” Dr Moore said.

“But we haven’t found it. We can’t see any changes in tensile strength, we can’t see any changes in shine or anything like that, so we haven’t been able to prove anything.”

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He’s not the only skeptic. According to Dr. Eric Pressly, one of the inventors of Olaplex, water does have the ability to open or close the hair follicle through absorption and swelling processes — however, he adds this has little to do with temperature.

“This is a very fast process, and the difference between hot and cold water is negligible,” Pressly told Into the Gloss.

A cool rinse might feel nice, but it won't necessarily result in royal shininess.

This was corroborated by Anabel Kingsley of the Philip Kingsley Trichological Clinic, who told the website: "[O]nce the hair has grown past the scalp, it is technically dead tissue — it neither contains blood vessels nor nerves. Rinsing with cold water therefore has the same effect on hair as rinsing with warm water does."

So, in other words, we're freezing our heads for no good reason. Of course, if you like a cool rinse for the refreshment benefits and/or bragging rights, go ahead — but don't expect to miraculously reflect light from every one of your hair strands afterwards.

RELATED: How washing my hair with oil-based products actually made my hair less oily.

That doesn't mean you need to abandon your quest for silky, shiny hair.

The very savvy Zoe Foster Blake has a few handy tricks up her sleeve, like drying your hair by patting it with a cotton T-shirt rather than scrubbing it with a towel — this will keep your hair's cuticles flatter, and thus look shinier (a good option for all you curly-haired readers). (Post continues after gallery.)

Foster Blake also recommends keeping your hair healthy through regular treatments and trims; and if you dye your own hair, select products with highly reflective, luminous finishes.

Interestingly, although a cold rinse apparently doesn't yield much of an impact on your hair, the cold blast button on your hair dryer does.

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"One thing that does [work] is the cold shock on your hair dryer. For example, if you're using a heat styler on your hair and you fire a cold shot at it, it then sets the style because it cools it back down again," Dr Tim Moore explains.

"Maybe people see that happening and think if they wash their hair and zap it with cold water, that it's good too."

Do you rinse your hair with cold water? Does it make a difference for you?