Your large water bottle on your desk is a good habit. But does it make your hair grow? The question comes up every day in consultations, and it deserves an answer that doesn't try to sell you anything.
The question is worth asking, however, because the answer isn't what you might think. We often read that you need to drink enough, and that beyond a certain point, drinking more won't help. It's a convenient way to avoid saying the most important thing, and we're going to set the record straight. When it comes to the practical steps that really make a difference, our step-by-step tutorial details the six steps of the Rituel Texture®.
When my hair was breaking, or my skin looked less than its best, my mother's first question was never about a product. She would ask me if I'd had enough water and eaten well. I never stopped believing she was right in principle, but today I know that it was never enough to save my length: the rest is all in the hands.
Ghana Elin, founderThe answer, and what it hides
Hair doesn't grow on your head; it grows beneath it. It's made in the follicle, a tiny factory buried in the scalp and nourished by the blood flowing around it. That's the only place where your water intake could have anything to do with your hair, and that's where the belief comes from.
Here's the real story. Severe dehydration is a general health problem that affects the entire body, including the scalp; no one disputes that it needs to be corrected, and that has nothing to do with hair. Aside from that, to our knowledge, no study shows that the amount of water you drink affects the growth rate, thickness, or strength of the hair fiber. Not in one direction or the other.
The cautious formula you read everywhere, "drinking enough prevents growth from being hindered," sounds reasonable, but it's not based on anything more than that. We prefer to remove it from our pages rather than keep it for the sake of convenience. Drink because it's good for you, not because you expect to gain inches.
The water you drink won't show up in your hair. What does show up is what you've done to it during detangling, drying, and overnight.
The two types of hydration
As soon as hair leaves the scalp, the story ends. The strand you style, whether it's ten, twenty, or forty centimeters long, is no longer connected to anything: it's made of keratinized cells with no blood vessels, no circulation, and no exchange with the rest of the body (Robbins, Chemical and Physical Behavior of Human Hair, 2012). No glass of water reaches that far, and no supplement does either.
That's exactly where the most common misconception comes from. A reader notices that her ends are dry and rough to the touch, that they soak up a moisturizing cream in a few hours, and concludes that she isn't drinking enough. She increases her water intake, waits three weeks, sees absolutely no difference, and concludes that her hair is a lost cause. It isn't: she's been treating an external problem from the inside.
There are therefore two types of hydration, and they have almost nothing in common. The one you drink is part of your overall health. The one you apply concerns the hair you already have, the hair in your hands this morning, and that's the only one that hair care can affect. The first can never replace the second.
How much to drink, and how to know
Since the question of how much to drink always comes up, we might as well provide the existing guidelines. European guidelines recommend a daily water intake of around two liters for adult women and two and a half liters for men, from all sources, including drinks and food (European Food Safety Authority opinion on dietary reference values for water, 2010). These are population guidelines, not individual prescriptions: they increase with heat, physical exertion, fever, or breastfeeding.
Above all, remember that food counts toward the total. Soups, fruits, vegetables, and yogurts provide a significant portion. A woman who eats a lot of raw vegetables and drinks a liter of water is not in the same situation as a woman who has a sandwich for lunch and drinks the same amount.
The best indicator is still the simplest, and it requires no effort: the color of your urine—clear when everything is fine, darker when you need to drink more. It's a rough but reliable guideline, used for this purpose in exercise physiology (Armstrong et al., International Journal of Sport Nutrition, 1994). If you drink little out of habit rather than by choice, a bottle left where you work is a better reminder than any notification.
What really determines length
You read everywhere that curly hair grows more slowly than other textures, and just as often the opposite. The figures given contradict each other from one article to the next, and we won't repeat any of them until a solid source can settle the matter.
What is observed in the salon, however, is beyond dispute: the difference in length is mainly due to breakage and shrinkage. Shrinkage is an optical effect; a curly hair coiled upon itself can appear much shorter than it actually is, and you only need to stretch it to see that. Breakage, on the other hand, is very real, and it explains most of the lengths that stagnate for years.
It happens in very specific places, and we have detailed them elsewhere rather than repeating them here: a comb passed through dry, bare hair, detangling starting at the roots, ends that are never trimmed, and excessive tension on the hairline, which is the recognized mechanism of traction alopecia in women who regularly wear braids and weaves (Khumalo et al., Journal of the American Academy of Dermatology, 2008). Our eight tips for retaining length and our article on curly hair length each cover these points.
How to hydrate from the outside
Since the hair fiber receives nothing from the inside, it all comes down to washing and the days that follow. The complete Rituel Texture® is done every seven to ten days: a gentle clarifying cleanse, then Le Shampoing Réparateur, then Le Masque Réparateur left on for ten minutes, under a shower cap if you have one.
Next comes the part we neglect the most: keeping that water in. La Crème Coiffante, applied to damp hair, helps retain the hydration provided during washing, and it's what makes the difference between ends that are still supple on the third day and ends that are already rough the next day. Between two routines, a drop of light oil on the ends can complement, but never replace, this.
One habit is worth correcting here, because it seems logical but isn't: wetting your hair every day, or spraying it with water every morning. The sensation is pleasant, the effect doesn't last all day, and this constant alternation of swelling and drying eventually fatigues the fiber. A well-done complete routine every seven to ten days is better.
What water won't do, no matter what anyone says
- Speed up the rate at which your hair grows.
- Hydrate dry ends, which must be treated from the outside.
- Replace a treatment when breakage is what's blocking length.
- Correct a deficiency or hair loss, which require medical advice.
When the question becomes a medical one
Persistent hair loss, hair falling out in clumps when detangling, thinning areas, and persistent fatigue alongside these: these situations cannot be solved with a water bottle or a treatment. They require a doctor, who will order a blood test if necessary and interpret the results.
We do not recommend any supplements, and that is intentional. A deficiency is diagnosed, not guessed, and too much of certain vitamins does more harm than good. Our article on foods that are useful for hair health details what food can do, and where its role ends.
Is your length stagnating despite everything you do?
Our experts will review your routine with you online and identify what is causing the fiber to break. For hair loss or any worrying sign, a doctor remains the person to consult.
Book a consultationFrequently asked questions
Does drinking a lot of water make hair grow faster?
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Sources
- EFSA Panel on Dietetic Products, Nutrition and Allergies, « Scientific Opinion on Dietary Reference Values for water », EFSA Journal, vol. 8, n° 3, 2010, article 1459.
- Robbins C. R., Chemical and Physical Behavior of Human Hair, Springer, 5e edition, 2012.
- Armstrong L. E., Maresh C. M., Castellani J. W. et al., « Urinary indices of hydration status », International Journal of Sport Nutrition, vol. 4, n° 3, 1994.
- Khumalo N. P. et al., « Determinants of marginal traction alopecia in African girls and women », Journal of the American Academy of Dermatology, 2008.
