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Dehydration won’t cause dandruff – but that doesn’t mean they’re not linked. Find out how to keep things from getting worse.

We’ve all heard that you should drink 8 glasses of water a day – anything less and you run the risk of dehydration. What you might not know is that not drinking enough water can affect your scalp health, particularly if you have dandruff.

First off, let’s establish what dandruff is, and why it’s not caused by dehydration. Then we’ll discuss the link.

What is dandruff?

We all have a yeast - a single-celled fungus - called Malassezia globosa on our heads.

Don’t worry though – it’s normal, and can be harmless.

This microscopic organism survives by breaking down the oils on your scalp, and leaves behind oleic acid as a by-product.

Unfortunately, about half the population are sensitive to this acid.

In these people, oleic acid can cause an irritation of the scalp, causing the body to increase skin cell production in an attempt to get rid of the irritant.

This leads to:

  • flaking

  • itchiness

  • redness

All the classic symptoms of dandruff.

So, to recap, the causes of these symptoms were Malassezia globosa, scalp oil, and how much you’re bothered by oleic acid. So far, we haven’t mentioned dehydration’s role in this reaction. So, what’s the link?

How dehydration affects dandruff

We know the reason for dandruff, but dehydration and its effect on the scalp can make the problem far worse.

This is because moisture is integral to the health of your scalp.

Dryness can lead to dandruff

When it’s healthy, your scalp keeps the bad substances out (irritants, pollution, germs), and the good stuff in (water, nutrients). 

When you don’t drink enough water, the scalp can become dry and damaged, causing flaking, itching, scratching…even broken skin. This weakened skin is less effective as a barrier between you and your environment. 

If you’re prone to dandruff, the irritants on your scalp trigger dandruff more easily than normal.


And dandruff can lead to dryness

It goes both ways. when you have dandruff, your skin’s moisture barrier is weakened, because it isn’t being produced at a healthy rate. 

Clinical studies show dandruff causes the scalp to lose more moisture, and become dry. The combination of dandruff and dehydration can also have serious consequences for your hair, which needs a healthy foundation to grow properly. Add the itching and scratching that can damage hair, and things quickly go from bad to worse.

It’s important to take appropriate steps, with a two-pronged treatment for your dandruff and dehydration.

You should always make sure that you’re drinking enough water – 8 glasses a day is the typical recommendation. At the same time, if you have dandruff, a hydrating shampoo will help keep your scalp in the best possible condition while you fight the cause of your dandruff.

This simple combination of solutions is the easiest way to make sure that your hair stays strong and healthy. After all, healthy hair needs a healthy scalp.

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