Princess Kate's new curly hair transformation might not last

When it comes to enviable hair, you'd be hard-pushed to find someone with more universally appealing locks than Princess Kate.

Whether she's posing for portraits, attending exclusive soirees or meeting the public, the Princess of Wales' hair is always picture-perfect.

While her hair is as gorgeous as ever in her birthday portrait, taken last summer, eagle-eyed royal fans noticed that Princess Kate's hair looked a little different, with more curls than we're used to seeing. According to hair expert Nicole Petty of top salon Milk & Blush, this could be down to cancer treatment, which can cause hair to change in texture.

Princess Kate's new curls

"Changes to your hair texture and colour as your hair regrows [after chemotherapy] are often surprising side effects of treatment," says Nicole.

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"While not all hair textures will change as a result of cancer treatments, it's not uncommon to see some differences in how your hair behaves.

"People may go from having straight hair their whole life to curly hair, known as 'chemo curls'. This is because the chemotherapy chemicals can attack not only your cancer cells but also your hair follicle cells, causing them to change."

While Princess Kate appears to be embracing her new curls, Nicole notes they might not be here to stay.

"It's important to keep in mind that this is likely a temporary change. It usually takes between six to 12 months for hair to return to its original texture, though some will have their new texture permanently."

Looking after Princess Kate's hair

Post-cancer treatment, Princess Kate's hair was likely more fragile, so her stylists will be taking extra good care of her mane, using softer, flexible brushes to limit breakage.

Haircare products should be considered too, with Nicole recommending avoiding products containing harsh chemicals. "Look for shampoos and products that are fragrance-free and derived from natural ingredients," she says.

The Princess of Wales regularly has her hair styled into waves and glossy blow dries, and her stylists are likely taking extra good care of her hair at present, with Nicole cautioning: "When it comes to styling your hair, you want to be as gentle as possible so, avoid heat and tight hairstyles where you can.

READ: Princess Kate is in 'remission' - how is this different from 'cancer-free'?

"If your hair has completely changed texture, such as going from straight to curly, you may also need to experiment with your styling routine to embrace this new hair type. Curls, in particular, are more susceptible to becoming dry and brittle, so take care to use nourishing treatments."

Princess Kate's hair colour

The Princess of Wales has been known to experiment with her hair colour, sometimes adding subtle blonde highlights, other times going for a darker, glossier hue.

At present, her hair looks close to her natural mid-brown shade – possibly as it’s not advised to dye your hair following treatment.

"You should avoid any chemical treatments, such as bleach, perms or dyes, for up to six months after finishing chemotherapy," says Nicole, adding that Cancer Research UK recommends cancer patients look into vegetable-based hair dyes, such as henna, as a gentler alternative to traditional dyes.

We look forward to seeing how the royal styles her hair for her next public outing.