Skin Breathing


If you saw the film Goldfinger, you will remember the scene where Bond was knocked out and woke up to find Jill Masterson (Shirley Eaton) dead after being covered in gold paint – supposedly, death by skin asphyxiation.

The erroneous idea that the skin ‘breathes’ – and can therefore be suffocated – was not confined to the 1960s. Like many urban legends it survives and thrives on the Internet to this day. Most commonly, you will find it on websites that proclaim the benefits of natural skin care and/or provide dubious lists of harmful additives to be found in skin and hair care products; the substance most frequently targeted for its ability to ‘suffocate the skin’ being mineral oil. The extracts below are typical of what you can find:

Extract 1
A derivative of crude oil (petroleum) that is used industrially as a cutting fluid and lubricating oil. Mineral oil forms an oily film over the skin to lock in moisture, toxins and wastes, but hinders normal skin respiration by keeping oxygen out.

Extract 2
It [mineral oil] comes from crude oil (petroleum) that is used in industry as metal cutting fluid. It may suffocate the skin by forming an oil film. Healthy skin needs oxygen, and it needs to release carbon dioxide. It should not be inhibited.

Extract 3
Petroleum-based [mineral oil] standard chemical skincare further causes problem by blocking skin respiration to suffocate skin.

These statements infer that skin gets substantial amounts of the oxygen directly from the air and that cutting it off from this source reduces oxygen absorption, impedes cellular respiration and adversely affects skin function. They are based on misconceptions about how porous the skin is and confusions about the nature of respiration.

The barrier function of the skin

One of the primary functions of the skin is to act as a barrier. Harmful microbes and chemicals are kept out and water is kept in so if this barrier is compromised our life is put at risk. For example, patients with severe burns, who survive the shock and trauma, frequently die from dehydration or infection.

What often misleads people is that the skin has pores. Even if we do not see them in the mirror, the beauty industry reminds us that they are there, and offers us cosmetics to reduce their appearance. However, these pores do not mean that the skin itself is very porous; their function is to allow the skin to release substances on to the skin surface, not to act as a passage for substances coming in through the barrier.

See also: Enlarged Pore and Blackhead Treatments

Again cosmetic advertising is partially at fault here. If we are to accept that the ingredients in an expensive skin cream are going to be effective, then we need to believe that they can be absorbed into the skin and affect the functioning of living skin cells. However, if a skin cream ingredient was able to do this, it would be classified as a drug not a cosmetic.

See also: What is a Cosmetic?

Intact skin is not totally impervious to all substances: some chemicals can penetrate the skin barrier, e.g., nicotine in nicotine skin patches; and some materials can restrict the flow of materials in the other direction, e.g., moisturisers may reduce moisture loss. However, if the skin is to function as an effective barrier against dehydration then it needs to be dry and a dry surface is not good at absorbing oxygen.

Gas exchange across the skin surface

In order for a surface to be able to exchange oxygen and carbon dioxide it needs three characteristics: it must be thin, moist, and have a large surface area. Surprisingly, oxygen is not very soluble in water and it requires more than a few bodily tricks to get sufficient oxygen into the blood to service our needs.

In the human body, the membrane that conducts the gas exchange is also associated with an extensive blood supply to carry oxygen away to the rest of the body and bring the carbon dioxide waste to it. As the membrane is very thin, it is also very delicate and, if damaged, extensive bleeding would occur. This is why our lungs are inside the body – they are there because they need protecting.

Being relatively thick and dry, the skin is not good at absorbing oxygen. Fortunately, living skin cells do not get their oxygen directly from the air but indirectly from the lungs through the blood supply. So, even if you paint the skin as in the James Bond movie, cellular respiration in the skin would be largely unaffected. It still might be dangerous to do it because if the paint restricts perspiration you could suffer from heat stress.

Cellular respiration, the skin, and ageing

In 1937, Hans Adolf Krebs published his work on the tricarboxylic acid (TCA) cycle and opened up the biochemical pathways associated with cellular respiration. The skin, like all body tissues, was shown to carry out cellular respiration and scientists interested in the functioning of the skin began to examine its effects.

Some scientists studying skin discovered that the level of cellular respiration was higher in younger than in older skin. This led to speculation that if skin respiration could be increased then perhaps skin ageing could be reversed. Given this idea, we can see why fads such as adding ‘oxygen releasing’ chemicals to skin care products, or applying cosmetic products in combination with oxygen could get some traction:

Extract 1
There are many ways for the oxygen to be administered. Dry oxygen gas may be used to send nutrient based oils onto the skin, liquid oxygen mixed with other oils can be misted onto the skin, and there are oxygen based facial creams or serums available. Oxygen facials may incorporate the use of various hydrogen peroxide creams. These are believed to help oxygen and water to permeate the skin. In each process, the oxygen is seeping into the skin, allowing the nourishment and revitalization of skin cells. In essence, the oxygen is improving your skin from the inside out.

Extract 2
Specially developed cosmetic products are sprayed onto the skin with pure oxygen. A gentle treatment ideal after cosmetic procedures, intensive-peeling treatments, for impure skin, for sunburnt skin or simply for a relaxing oxygen massage.

Extract 3
The application of oxygen under hyperbaric pressure allows the epidermis to maximise its oxygen surface level concentration. This pressure also assists in the rapid absorption of the intraceuticals serum that is enriched with Hyaluronic Acid (the skin’s natural moisturiser) Vitamins A, C and E as well as Green Tea extract and Aloe Vera. The results you see when you leave the clinic are visible and lasting. The gentle process is non-invasive, painless, and safe both during and after the treatment.

Of course this all sounds rather silly. Surrounding the body with oxygen is not going to markedly increase the supply of oxygen to the living skin cells. Besides, as we now know, oxygen has a darker side.

Oxidative stress

The discovery that free radicals are by-products of cellular respiration put a dent in the marketing idea that increasing oxygen will counteract skin ageing. The body continuously produces harmful oxidants – such as superoxide and hydrogen peroxide – from internal sources such as mitochondrial respiration, and it can also pick them up from exposure to environmental agents such as smog, cigarette smoke and UV radiation. The body has a system of antioxidants to mop up these free radicals but, if placed under oxidative stress, elevated levels of free radicals may result producing an increased risk of diseases such as cancer. So, even if by some chance it was possible to increase oxygen absorption through the skin, this might be a bad, rather than a good thing.

Free radicals were something that cosmetic manufacturers could get their teeth into. Antioxidants such as vitamins A, E and C have been in cosmetics for a long time to help stop oxidative changes in cosmetics – when exposed to the air, cosmetics can oxidise and change colour in the same way that an apple goes brown after you bite into it. Cosmetic manufacturers suggested that the antioxidants they put into their cosmetics would penetrate the skin and reduce the signs of skin damage and ageing caused by oxidation. However, even though there is evidence to suggest that some absorption of vitamins in skin creams does take place, it would be cheaper, and more effective, simply to get these vitamins in your diet.

Updated: 23rd February 2017

Sources

Sagarin, E. (Ed.). (1957). Cosmetics: Science and technology. New York: Interscience Publishers, Inc.

Wells, F. V. & Lubowe, I. I. (1964). Cosmetics and the skin. New York: Reinhold Publishing Corporation.