I recently received correspondence from someone who asked this particular question. I had to write back and ask if the person was talking about being dehydrated or using water with excess chemicals when washing or caring for one’s hair. The person clarified that they were asking about being dehydrated because they’d been shedding and losing more hair than normal over the last few months and had recently read that you need to drink eight glasses of water per day. Since they didn’t even begin to meet that requirement and could think of no other reason for their hair loss, they wondered if dehydration might be the cause. But, they were also interested in hearing more about the water quality issue, so I will discuss both concerns in the following article.
Dehydration And Hair Loss: First, I have to admit that there is a lot of differing opinions when it comes to determining how much water a person really needs in order to stay well hydrated. Medical advice differs on this. It used to be that it was thought that the minimum requirement for optimal health was 8 – 10 glasses of eight ounce cups of water per day. Lately, the medical community (or at least some members in it) seem to be backing off of these numbers by a little bit.
Regardless of the actual number of glasses that you consume, a good way to tell if you are getting enough water is to make sure that your urine is pale and / or clear and also to make sure that you are regularly going to the bathroom. If this is happening, then it’s a pretty good bet that you’re well hydrated no matter what the actual amount of water that you’ve consumed might be. (Also, you get water in other ways besides drinking it. Many foods (in particular fruits) contain a decent amount of water.) And what you’re drinking doesn’t have to be water. Juice and other drinks count too.
In terms of hair, like all of the systems that the body has to support (organs, skin, etc.) water is going to be an important component of this. Think about this. Hair strands themselves are 1/4th water. Generally speaking though, it’s more likely to see hair that is brittle, dry, and breaking off, or not growing properly as the result of not enough water consumption rather than hair that is falling out. Normally, with mild dehydration, your hair, skin, and nails just won’t look as shiny or as healthy as they should. They might also grow slowly or not at all.
However, with severe dehydration, you can see circulation to the skin, scalp, and hair roots shut down as a measure of preserving the body’s reserves. This severe state can cause some hair loss and shedding. It can also make other problems that can contribute to hair loss (like dandruff, psoriasis and androgens) worse. But, with a relatively normal diet that includes beverages, it’s relatively rare to see this level of a problem. That’s not to say that it can’t happen. But, it is somewhat rare from my own experience and research.
As far as poor quality water or a high amount chemicals when washing your hair (like chlorine,) you will generally see the same types of aesthetic problems – dry hair that easily breaks or is not manageable. You’ll typically see it breaking off rather than falling out.
If you suspect that this may be a problem for you, it’s very easy to fix this issue. Drinking more water is easy, free, and worth a try to see if you obtain any relief. If this doesn’t work, you may want to look at other causes for your hair loss like telogen effluvium (TE,) other medical issues, or other common hair and scalp concerns like AGA (androgenic alopecia) which is by far the most common cause of hair loss.