Can it help hair grow? Will it strengthen and soften my strands? Do I have to cook a batch to get all the goodness? We rounded up the research to bring you the facts about the hair benefits of rice water.
Upcycling—the concept of creating something new from discarded materials around the home—is still a relatively recent sustainability trend. But the ancient Japanese, living the philosophy of kirei, have for centuries been reusing and repurposing what might otherwise be thrown out. One prime example that’s re-entered the social conversation: rice water.
Japanese women have always used yu-su-ru, the nutrient-rich water left over after soaking rice, for its hair-care benefits. The court ladies of the Heian Period (794 to 1185 A.D.) were said to comb their hair, which often reached the floor, with rice water.
Those benefits have stood the test of time, with rice water for hair recently trending on the least ancient mode of communication: social media. Influencers are raving that rice water smooths their frayed, split ends and makes their hair so glossy, they can almost see their reflection in it.
Let’s take a closer look at why and how you should use rice water, too.
But first: What exactly is rice water?
Basically, it’s water that’s been used to soak rice before cooking. People soak rice for several reasons: It shortens cooking time, enhances the scent of aromatic rice varieties (such as jasmine and basmati), and removes the starch dust naturally created when grains rub against one another.
When the starch dissolves into water, it becomes a liquid that’s rich in, yes, starch, but also nutrients like amino acids, vitamins, and antioxidants. The starch in the rice water helps fortify strands of hair and add shine, while the other nutrients nourish the scalp.
So how can I use rice water for my hair?
Social media stars have devised all sorts of ways to incorporate rice water into their routines—letting it soak overnight or combining it with apple cider vinegar—but it doesn’t have to be that complicated. You don’t even need to whip up any rice.
MyKirei by KAO Nourishing Shampoo and Conditioner have done the work for you, pairing vitamin-rich rice water with moisturizing Japanese tsubaki extract, so you can easily keep your scalp healthy and your hair glossy. There aren’t many negative side effects of rice water on hair—in fact, we can’t think of a single one.
We can think of 5 reasons you’ll want to use rice water
The recent chatter about rice water isn’t all hype. The ancient Japanese tradition has shown real benefits of using rice water for hair.
1. Rice water can help support healthy hair growth
“There's some evidence that rice water is able to absorb into the hair and help hair grow faster by elongating the growth—or anagen—phase, of the hair,” says Nava Greenfield, M.D., a dermatologist at Schweiger Dermatology in Brooklyn, NY.
That’s worth mentioning since research shows that stress, one of the most common sources of temporary hair loss, can trap hair in the telogen—or resting—phase of growth. Stretching out the growth phase with rice water could offset that imbalance, since many people anecdotally report longer hair.
2. Rice water improves scalp health
What’s good for the scalp is generally good for the hair. A study in Acta Dermato-Venereologica found that bathing in rice water can repair the skin barrier function in those with atopic dermatitis or skin irritated by sodium lauryl sulfate (a common but potentially harsh cleansing ingredient).
With rice water keeping the scalp hydrated and healthy, you won’t need to worry about the side effect of a compromised scalp barrier—dryness, irritation, and unhappy hair follicles. Furthermore, MyKirei by KAO hair products do not contain sodium lauryl sulfate in the first place!
3. Rice water may strengthen hair
If your hair tends to be weak or brittle, or has endured years of heat styling, color processes, or chemical treatments, a hair routine with rice water may be in order: A paper published in the Journal of Cosmetic Chemists noted rice water’s ability to strengthen and soften hair.
The ingredient also “may increase hair elasticity,” says Greenfield. Hair elasticity—the length that a strand of hair can stretch before springing back to its original state without breaking—is a sign of hair’s overall strength. So, better elasticity means stronger hair.
4. Rice water can decrease frizz
Do you have a frizz halo on humid days? Rice water’s smoothing abilities will really shine on you. “It may reduce surface friction of hair shafts,” says Greenfield. Friction, one of the top sources of frizz, physically lifts up the hair cuticle—precisely why reducing it with a dose of rice water can make a big difference.
5. Rice water helps repair damage
One special component of rice water called inositol may actually restore hair from the inside out. “It’s not exactly understood how rice water can help repair damaged hair, but it may reduce the level of androgens and act as an anti-inflammatory,” says Greenfield. (Androgens are a class of hormones that can inhibit the hair follicles, weakening hair or even leading to hair loss, per a 2020 study published in the International Journal of Molecular Sciences.)
Further research suggests that inositol not only supports hair elasticity from within the hair shaft, but may also protect it from future damage, too. All in all, rice water is a natural way to help soften, strengthen, and detangle hair.
Rice Water and the Anagen Hair Phase: Biological & Pharmaceutical Bulletin. (2014.) “In Vivo Hair Growth-Promoting Effect of Rice Bran Extract Prepared by Supercritical Carbon Dioxide Fluid.” pubmed.ncbi.nlm.nih.gov/24389480/
Androgens and Hair Strength: International Journal of Molecular Sciences. “Hormonal Effects on Hair Follicles.” (2020.) ncbi.nlm.nih.gov/pmc/articles/PMC7432488/#sec3-ijms-21-05342title