Does Hot Water Clean Better Than Cold? Yes and No.

In a recent thread I saw a few members discussing whether to use hot or cold water when cleaning the lather off your face.

They didn't have any definite reasons on why they felt that way but knew what worked best for each of them.

I wanted to make a reply without sidetracking the OP's thread so I thought I would get the basics of the science out here.

Now it's been years since I've been in a science class but I had a good grasp at it. I had to look up some spellings but I had the basics of it still stuck in my head. I may not be 100% on everything but I'm pretty sure I'm close. Like I said it's been a while.

Washing With Cold vs Hot Water.

Water is good at cleaning because it's highly attracted to hydrophilic molecules and will push away other water molecules to instead bond with the hydrophilic molecules which causes the hydrophilic substance to blend with the water. Hydrophilic substances are anything that easily becomes soluble in water like sugar & salt.

Cold water will pretty much clean in the same way as hot water it just takes longer to do it. The kinetic energy of hot water causes the water molecules to spread out and move faster which makes them bond with the hydrophilic molecules easier and faster. More space in between water molecules means there are more water molecules able to reach the hydrophilic molecules to bond and since they are moving at a faster rate they find and bond to them faster.

Ok but how does this help any grease or oil on your face since everyone knows oil doesn't bond with water right?

Well oil and grease are hydrophobic which means water has a stronger bond to other water molecules than it does the hydrophobic molecules and won't bond with them. It just kind of goes around them. That's where soap comes in!

To make it simple soap has two ends one that is hydrophobic and the other is hydrophilic. The hydrophobic end breaks up the oil by bonding with tiny drops of the hydrophobic oil while the hydrophilic end bonds with the water molecules. In turn the oil is pulled off your face and suspended in the water.

Shaving With Cold vs Hot Water.

So it is basically true that hot water is better to use for cleaning off your face and equipment while shaving but since you are shaving your face you do have to take your skins reaction to hot and cold water into effect.

Cold water will contract your skin causing your hair to stick out straighter and stiffer which will make shaving them easier.

Hot water will make cleaning your skin easier but it's said that it can also dry out your skin by removing natural oils.
I know heat also brings fresh oxygenated blood to the surface and sweat causes salt to cool and dry the skin.

The question is does the soap strip these oils from you face anyway and the water washes away the salt?

With helpful info from SRNewb, hot and cold water doesn't actually "open" or "close" your pores. I do wonder does the contraction and swelling of the skin effects pore opening size at the surface?

I'll update this section if any new info is added.
http://badgerandblade.com/vb/member.php/83554-SRNewb

Conclusion?

What I'd advice is going back and forth between warm and cold water which I believe a lot of member here do.

I use warm water while making my lather, then I switch to colder but not freezing water to shave. I use warm water to wash the soap off my face the rinse with cold water before I put on my aftershave.

Use the correct temperature of water to get the required reaction at the necessary time.

Everyone has their own method but I thought I'd give some helpful info if anyone was interested on why those methods work they way they do.

If you know for a fact that I was off on anything I said please feel free to mention it. Like I said it's been a while.

Thanks for the info !

interesting , never really thought that much about it . You sir have now piqued my curiousity.

I do not believe pores open or close. There are no individual muscles connected to your pores, they are simply holes in the skin. They do not widen or narrow. MHO.
http://health.howstuffworks.com/skin-care/cleansing/myths/pores-in-hotter-water.htm

http://www.besthealthmag.ca/look-great/skin/myths-and-truths-about-your-pores

In terms of cleaning I would say warm-hot water just breaks down the soap faster and makes cleaning soap easier. I usually only clean my bowl, mug, and brush with semi-hot water but I always rinse my face with cold water like you, not freezing.

People think that those with sensitive skin should use cold water. I would say freezing cold water is going to dry out your skin, as does hot water. Luke-warm is really the best for those with sensitive skin.

After the thread last night I gave it a google - http://news.nationalgeographic.com/...washing-hands-hot-water-wastes-energy-health/

As you say, it is the soap that does the cleaning of oils, not the water itself. So the question is does soap bond with cold water? It does indeed. So I can wash the left over shaving soap off of my face with cold water.

From your points on energy on hot water, it might do it faster, but if you then do a cold rinse after a hot rinse, why not just do two cold rinses? Wouldn't this hot rinse increase the issues that we then try to reduce with the cold rinse?

Therefore, two cold rinses that remove all of the soap makes more sense to me than one hot rinse to remove soap then a cold rinse to cool.

justino_14 said:

In terms of cleaning I would say warm-hot water just breaks down the soap faster and makes cleaning soap easier. I usually only clean my bowl, mug, and brush with semi-hot water but I always rinse my face with cold water like you, not freezing.

People think that those with sensitive skin should use cold water. I would say freezing cold water is going to dry out your skin, as does hot water. Luke-warm is really the best for those with sensitive skin.

Click to expand...

Hmmm...I remember a poster on another thread stating that hot water dried out one's skin, and that cold water did not.

Is there a dermatologist in the house?

My $0.02: I wash face and hands with warm water (shower too!)...just feels better/cleaner. I have tried cold-washing hands and don't notice any difference...this time of year they are dry -- a function of the dry air I would think.

Effy said:

After the thread last night I gave it a google - http://news.nationalgeographic.com/...washing-hands-hot-water-wastes-energy-health/

As you say, it is the soap that does the cleaning of oils, not the water itself. So the question is does soap bond with cold water? It does indeed. So I can wash the left over shaving soap off of my face with cold water.

From your points on energy on hot water, it might do it faster, but if you then do a cold rinse after a hot rinse, why not just do two cold rinses? Wouldn't this hot rinse increase the issues that we then try to reduce with the cold rinse?

Therefore, two cold rinses that remove all of the soap makes more sense to me than one hot rinse to remove soap then a cold rinse to cool.

Click to expand...

You're correct that two cold water rinses or basically one long cold water rinse would clean the soap off your face. I do prefer a short warm water rinse followed by a short cool water rinse though.

I went with a cool water have yesterday and got a BBS shave in 2 passes. Now, I could have just got lucky. Did 1 pass N, S then the other S, N....my neck also feels much better.
From now on, prep with warm, shave in cool......use a wash cloth for final clean up

SRNewb said:

I do not believe pores open or close. There are no individual muscles connected to your pores, they are simply holes in the skin. They do not widen or narrow. MHO.
http://health.howstuffworks.com/skin-care/cleansing/myths/pores-in-hotter-water.htm

http://www.besthealthmag.ca/look-great/skin/myths-and-truths-about-your-pores

Click to expand...

Thanks for looking that up!

I think the "open" and "close" terms I used were incorrect. I never thought of pores opening up and closing tight like you open or close a window I figured they were always open holes but as your skin contracted or swelled due to the water temperature it would effect the size of the pore holes?

I knew the science better than the dermatology it seems hah. I'll have to look into that more.

I think the terminology comes in to symantics when we talk of "open" poors. They may not open in the sense that we open our eyes, but from the contracting or expading of the skin they can BE more open or more closed. Think of how when you smile you can cause a cut to "open" - it doesn't open itself in that manner of speaking, but from the effect of the skin it is then said to be open.

Don't get too hung up on it.

I guess it depends on what clean means to you. Hot water cuts skin oils and any grease for that matter better than cold water. As far as, just removing dirt cold water may actually be better.

Hot water dissolves things faster.
But if you have hard water hot, it contains more dissolved solids than hard water cold and leaves more residue on razors, brush handles, etc. unless you blot dry instead of air dry.
As far as skin goes, it's your choice; I'm not ready to start taking cold showers.

I am tepid on this issue.

Hot does for me!

I like cold water to rinse my face, hot water to soak my brush, warm water to rinse my razor, more cold on my face between passes, and a warm washcloth at the end to take off the soap residue.

Man, isn't indoor plumbing the best thing?