I have received a number of emails and calls recently, concerning some websites stating “Self tanners Destroy Skin” “DHA Damages DNA” “DHA Ages skin” etc. See below for example of the letter I received today.

Judy asks:

“When doing some research, I came across the website below, which cites studies showing that DHA may cause premature aging. Most concerning are the studies regarding free radicals and DNA damage. What are your thoughts on this? I have limited knowledge on the science behind sunless tanning. I am hoping it is unfounded like so many other “concerns” in the beauty industry. I have listed the website below. Thank you for any help you can provide.

First I am so glad Judy emailed me one of the articles. I did not link to it, as a quick Google search pulls them up, and there are more then one. And I personally am not going to be a part of further increasing “hits” on sites that Use fearmongering and Fake News scares to generate headlines. Note, these are not “new” studies, nor new information. These “Faux Facts” have been circulating for at least the past 20 plus years, and are recycled again and again.

Here was my reply to Judy:

This is actually  based on old (and inaccurate) “news”. So please be at ease.

They are recycling a number of old studies, and stating/reaching incorrect/incomplete conclusions.  But are not looking at current newer data. Or all the studies around. You cannot Cherry Pick a study, or three (in this case) and present that as a forgone conclusion, this is not how good science works.

One or two “quoted” studies do not show the entire picture. Rather you would need to look at all the studies out there, how they are done, are they Peer Reviewed, and medically sound, can they be duplicated, and how do they apply to real world activities and use. The articles I have seen on the internet, message boards etc – are only pulling one or two studies from the large amount of complied data to “prove” their case.

The Quoted “DNA damage on Mice” is a study from 18 years ago, using cut mouse skin in a test tube (submerged in DNA solution)  for the damaged DNA conclusion.  Yes, it is true, living tissue submerged in DHA of “unknown” concentration (was it 5% or 50%, which was not stated, but does matter) will cause damage to the skin. Almost any substance will also cause similar damage, even water.

They also did paint some solution, of unknown percentage, on the skin of hairless mice, but no reference was made to how far it penetrated or the “damage” level actually found from the painted on only product. Only that some oxidative damage occurred. Was it 1% or 50%? That answer was never provided. So they then Submerged the cut skin into a test tube to produce the damage for the conclusion reached.

Keep in mind, hairless mouse skin is not identical to human skin, it is a special mouse bred to be more reactive to inflammations, cancers, and tumors then  the average mouse, or the average human. So essentially an Ultra Sensitive mouse. They come form genetic lines, bred to increase the reaction and sensitivity. So though the information provided is helpful for general study information in a broad sense, it is not going to necessary be the same, or even close to what humans with much thicker skin would experience with product “painted” on their skin in a properly formulated product, at a specific regulated DHA percentage.

The article (that Judy mentioned) also forgot to mention the more current updated studies (which was actually a side link on the page of The linked to “Mouse DNA study”) that showed DHA is generally shown to be safe for human skin use, in a correctly formulated finished sunless tanning product.


This study notes among other things, that the DHA tan reaction and chemical skin reaction is limited to the dead skin surface layer. And no systematic absorption was noted (Section 2 Quality and Health aspects paragraph 2). Many other well founded studies back this up.

Self-Tanners have been shown in a number of studies, to be a surface active product. Not something that easily or actively, penetrates down to living tissue (which is where the DNA is stored). DNA cannot be damaged, unless the DNA is exposed to the DHA ingredient.

But we still have the increase in Oxidative damage on the skin surface, which increases inflammation, and “in theory” would increase UV Damage, Skin aging, and collagen and elasten breakdown in the skin.

Oxidation on the skin, Sun Damage, Anti-Oxidants and pH in Self tanners:

This same article noted that if the Tanning product is below 10% – 15% DHA (depending on the study), and around 5 pH (all self-tanners are at this pH level) that any skin free radical damage/oxidative damage is dramatically reduced, and adding anti-oxidants into the Self tanner formulation would  additionally prevent the feared oxidative issues. That is the purpose of Anti-Oxidants in skincare products, to stop, and neutralize oxidative damage which comes from many things (Aging, UV Exposure, Stress, Second Hand Smoke, Heath issues, poor diet, strenuous exercise etc)

Every self-tanner I have seen, on the USA market currently contains anti-oxidants added into the formulas. Most commonly in the form of natural plant extracts and active antioxidants. (things like Aloe Vera, Green and Black Tea extracts etc.) But also found in the addition of Vitamins C, A, D and E. All Tampa Bay Tan Solutions, sprays, Lotions, Mousses, scrubs, and Body wash products are high in Anti-oxidants from a range of sources.

Most sunscreens also add in Anti-Oxidants as well, to better mitigate UV oxidative damage to the skin. So if you are going outdoors, and wearing your sunscreen, as you should, this provides even further protection for oxidative damage.  If you have just applied your self tanner, an aerosol sunscreen is a great, easy to use option.  But lotions also can work, just wait an hour or two after tanning, so you have less impact on the sunless tanning application.

Many standard body care moisturizing lotions also are Anti-Oxidant rich. So using one as your daily moisturizer also adds “Good For Your Skin” anti-oxidants into the mix. Anti-oxidants can store in the skin for a period of time (depending on the type used) And your body is happiest with a wide range of different anti-oxidants, rather then one star player. You can apply them topically in cream, serums, lotions and also ingest them orally in supplements or your diet.  (I do all of the above)

If you use Vitamin C on your skin regularly, you are using a very potent anti-oxidant, that actually acts within the skin for about 3 days after use.

Note: The UV exposure/Sunless tanner Oxidative issue Increase is related to a freshly applied tan, while it is actively going through the self tan chemical reaction skin color change (which is active the first 6 hours roughly). A tan that has already developed would not have this same reaction.  So the concern is during immediate post application timing.

You can also just apply your self tanning product before bed, to minimize any UV exposure if you prefer.

Current Formulations and Safety:

DHA in self tanner use has decades of real world use in the consumer market, which has shown historically to be safe, when used as directed. Even when used in a spray environment, the largest concern has not been skin related, but “possible” inhalation related.  No toxic issues have been seen at this point, but further peer reviewed controlled study in an enclosed booth environment with various concentrations would be beneficial.

Some studies done in Europe with spray solution at 20% levels in an enclosed tanning booth, did not show an issue.  And were shown to be safe. But there is always a concern for those with unknown allergies, or respiratory concerns, which make nasal filters a recommended options for all Booth users, and good ventilation and possible filters for Spray Tanning Techs, as well as Pregnant clients or those with breathing concerns.  But this is due more to increased absorption through nasal mucus membranes and lung absorption.

This would not apply to lotions, or most Spray Tan applications with correct equipment adjustments and correct good ventilation.  If you blow your nose after spraying clients, and blow out brown goo – then you have poor ventilation, and should correct this. (and or purchase nasal filters)

Current DHA sunless formulations, are highly stabilized, and less likely to contribute to oxidative concerns,  skin aging, collagen damage etc. (even with UV exposure). Using them with anti-oxidants mitigates the majority if not all associated oxidative damages.

Both the USA and UK Governing bodies, who look at all the scientific studies (not just a few cherry picked to create a catchy headline) have concluded DHA and Self tanners are safe for skin use, and will not propose a health risk to the consumer.

Self-tanners are :

Applied to Intact Human skin, with a protective barrier surface covering it. 

The “offending ingredients”, in this case they mention DHA,  never reach living tissue, nor cellular DNA. Which is where damages would occur.   If they did reach living tissue so easily – you would have worse things to worry about. For example EVERY soap or shampoo used in your shower, every lotion or cosmetic placed on your skin, – all would be equally damaging to cell tissue in the body – Thankfully this is not the case.  We know this because of product formulations which are required to meet certain safety parameters that regulate which ingredients can be used, and how they are used in the consumer market.

And because we are not all walking around with our skin totally freaking out because it is being relentlessly assaulted and severely damaged daily when we take showers, apply lotion etc.

This skins protective barrier surface is very dense, and multilayered, and includes not only protective physical tissue, but also a layer or fats and oils, and chemical components, that all work together to protect the live/living tissues below. It Keeps out viruses, bacterium and also cosmetic grade level chemicals (skin care products, makeup, cleaners etc.) pollutants, second hand smoke, in the environment.  This is all part of the bodies natural protection and defensive system to protect the body from the surrounding environment.

Skin care products are regulated in the USA and Europe. The molecular size MUST be of a certain particle size, which effectively prevents them from penetrating deeply into tissue, thus they do not have easy access to deeper tissue layers, body cells, DNA, blood stream and so forth.

Skin – Like A living Screen:

Think of an open window in your home, with a metal screen on it. The screen allows fresh air into your home, but keeps out Moths and bugs, because the openings in the screen mesh are to small for a moth to pass through, so he cannot break through the protective barrier (screen) and come into your home. The skin is much the same, keeping out the large molecular invaders/moths.

There are certainly chemicals that can pass through the skin barrier, but to do so they need to be enhanced with chemical penetration enhancers, and in most cases also need a protective plastic/rubber patch, or thick ointment layer, over them to increase absorption.  Or in the case of an industrial cleaners, require warning labels requiring gloved use.

Even with this they do not absorb easily, as the skin still keeps out most of the product, so the dose need to be super high to get a small amount through the skin into the blood stream and inner tissues. In the case of patches, or Medical ointments, they need to be worn 24 hours a days, everyday to work.  In the case of industrial cleaners, the concentrations are very high.

An example of a medical use patch, with skin delivery,  is a Nicotine or Hormonal patches.   Both use specialized ingredients to enhance absorption, high doses of the medicine product to get a “small” dose inside the body , specialized protective cover, or specialized thick occlusive cream delivery systems, and require prescriptions.

Products of this type are also heavily regulated, and can only be obtained with a Prescription from a Doctor, or with a Pharmacists approval.

Self-Tanners could not use these same penetration enhancers or delivery systems. (as they are regulated)

Also a self-tanner works best on the “Surface” of the skin, not deeper tissue, as it needs the protein matrix of the skin dead surface layer to product the brown coloration. It will not tan cut or open skin tissues. So it would not work correctly, if it penetrated to deeply.

The Takeaway – Does DHA Damage the skin?

Sunless tanner ingredients are not products made in a small enough molecular size to pass through the skin surface easily, a small amount may come in, but the body easily breaks it down and disposes of it. It does not circulate in the blood, or tissues, based on current medical studies. It needs to reach the DNA (inside each living cell , underneath the dead skin layer) to destroy it.

If you add sunless tanners, or shampoo, or hand soap, or even salt water – to a test tube containing living tissue cells – then Yes, you do have cellular and DNA damage. But note,  this will happen with ANY cosmetic product, and even salt or tap water will damage living cells and DNA in a dish – But this in NOT how we use sell tanners at all. They do not reach the living cells nor the DNA of those cell because of the protective skin barrier.

Oxidative issues come from many many sources we encounter daily, not just skin care products or self tanners. But current product formations in stabilized forms, and with the additional of quality skin care activities such as potentent Anti-Oxidants neutralize free radical oxidation concerns.

What about Vitamin D concerns?

Does Self Tanner use prevent the body from producing Vitamin D – No it really does not. Or at least not significantly. Sunscreen would be more likely to cause this, and even with sunscreen use, this is not the full picture.  Sunscreens are generally not applied with correct amounts (most people use about half of the recommended thickness, and do not apply every 2 hours as recommended for full protection, nor do most people use 30 plus SPF products. (even an SPF 100 sunscreen does allow some UV to penetrate, though at reduced levels)

Current Sunscreen recommendations are 30 SPF applied liberally, daily to all exposed skin. This only prevents 97% of UVB penetration (not necessarily blocking UVA) and is dependent on amount applied, reapplication timing, sweating, swimming, light reflection from environment etc.

UVA and UVB Both penetrate through a sunless tan. The UV Protective factor is only about a SPF of 4, and this is on a FRESH heavy sunless tan, and fades daily just as the tan does.  You can both sunburn and suntan with a sunless tan on the skin. (you need UV penetration to tan or burn)

Even with a SPF 4, lots of UV still reaches the skin, so Vitamin D is still created in the body.  More then enough, generally to continue with Vitamin D synthesis. The body stores Vitamin D, so daily Sun Exposure is not required. And only about 15 minutes of UV exposure will produce lots of Vitamin D.

Current Studies do not indicate that daily sunscreen use prevents formation of Vitamin D. And a sunless tanner has a very low SPF value compared to the minimum sunscreen requirement of 30 SPF. An Australian study that’s often cited showed no difference in vitamin D between adults randomly assigned to use sunscreen one summer and those assigned a placebo cream.

However even for those who NEVER wear sunless tanners, it’s a great idea to add Vitamin D supplementation to the diet, as in the USA and UK about 50 % of adults do have Vitamin D shortages – not just because of Sunscreen use, but because most of us work indoors all day, and we do not consume Vit D in our Diets in high enough levels.

Vitamin D is a very inexpensive supplement, and you only need a very small amount daily (4000 IU daily is more then enough for most adults) the capsules are very small, very easy to take, and super cheap – a years supply is about $10-$15.

On a side note – sunless tanning increasing skin aging – I can say in real world use, defiantly no. I am 54, wear sunless tanners only, and have since 1989, and generally regularly wear sunscreen most days. I do not UV tan. I look much younger then all my family members and most of my friends of a similar age. I am often mistaken to be about 35-40.  I am often told I look like the younger Sister, when I am with my sister who is actually 7 years younger than myself.  Most people believe my 26 year old daughter and I are sisters. Not Mother and Daughter, and my Husband often has some explaining to do when people see the picture of us on his desk at work..  ***smile***

And its not genetics, as my Mom, Sister, Aunts all have aged “harsher” then I have. But I do care for my skin, using lots of anti-oxidants daily, and use sunscreen daily, and no UV tanning.

My skin collagen, and Elasten is in excellent shape for a women of  age 54.  So says my Doctor.


Further reading:

Does Sunscreen Use Prevent Vit D formation:



A broad picture of DHA Studies compiled: