Today’s problem comes from everyone’s favourite British beauty blogger, BritishBeautyBlogger, from whom I have learned a great deal so it is nice to pay a little back.
Hi Colin.. okay.. I have been using a liquid magnesium complex in my bath which says that you can absorb it through the skin. Can all vitamins be taken in this way or is it specific to magnesium? I just keep thinking it is the easiest way in the world to take vitamins so in theory could you have like a multi-vitamin bath every night that does the same as a tablet?
Can I answer the second question first – I think there are some problems with using a bath to get your vitamins. There are two main reasons why soaking in a bath is not going to be a very good way of obtaining vitamins. The first is that to have any chance of getting into your body the concentration in the bath would have to be greater than the concentration in your body. So to have any chance you would have to really load your bath so full of vitamins that it would be very expensive to do so.
For example a leading UK health supplement company recommends daily intake of 2 vitamin C tablets containing 500 mg per day. (This is incidentally, a very very generous dose). You have about 6 litres of blood, and a bath might have 240 litres of water in it. So you would need to add 40 times the number of tablets to the bath water that you would have to take.
Even though vitamin C tablets are relatively cheap, this doesn’t seem like a cost effective way of avoiding a bit of mouth activity. But I don’t think it would work even if you can afford to get enough vitamins into the bath. The skin is a really effective barrier to most things it comes into contact with. I doubt if very much in your bath water would be able to get through even if it were at the correct concentration. Very few drugs can be administered via patches for exactly this reason.
But that doesn’t mean that you can’t get some benefits from bath additives. Bath emollients are a great way of calming down dry and irritated skin, particularly for children. There are also bath salts which might well be beneficial to the top layer of the skin. If your liquid magnesium complex is claiming to do anything for your general health I would be very skeptical. But I can easily believe it might do your skin some good. Metals like magnesium seem to have some role in the skin that hasn’t yet been worked out, but lots of people find that Epsom salts and Dead Sea salts, both of which are magnesium rich help make their skin less itchy and can reduce its redness.
The scientific evidence to back this up isn’t very thick on the ground, bit there is some – see my post on Dead Sea Salts for some background. There is also some evidence that metals like magnesium and zinc do have an effect on the skin.
So my conclusion is that a bath might be a good way to improve your skin but won’t help with nutrition.