How Birth Control Pills Treat Acne
Explaining the futility of the root cause concept
In reply to the last post about the lack of evidence linking contraception use with infertility, someone on Instagram mentioned they had seen a claim in the naturopathic community that stopping the birth control pill caused acne. I replied, explaining the estrogen containing birth control pill actually treats acne. If the birth control pill is stopped, acne that was being treated by the pill may reemerge after the therapy is stopped. For a naturopath to claim that is causing acne is either disingenuous or reflects a lack of understanding of how the pill treats acne (as well as the mechanisms behind acne).
And then someone else countered with a claim that oral contraception should not be used for acne because it doesn’t treat the “root cause.” And that, my friends, meant it was time for a teaching moment. We’re going for a two-for-one here—tackling the fallacy of “root cause” for medical conditions and also explaining how the pill treats acne. So buckle up.
Naturopaths and functional medicine practitioners love to use the term “root cause.” The idea is there is one or perhaps two main or root causes of any medical condition and if only these were treated then a true cure would be possible.
This concept of “root cause” distills medically complex conditions—most medical conditions are complex, even seemingly simple ones such as acne—down to something that sounds simple and fits with a good/bad binary. Typically, the naturopathic and functional medicine root cause is identified with tests not typically covered by insurance. With the breadth of genetic and hormone tests now available, it’s easy to point to a variation in a gene or a slight difference in a hormone level and proclaim, “Eureka!” This naturopathic root cause is subsequently treated with “natural” supplements or homeopathic pills.
The other aspect of root cause is the insinuation that doctors like me are “suppressing” the condition, not treating it. This makes no sense, so it is hard to unpack. Medicine is multifactorial, and treatments are designed around what works (makes the condition or symptom go away) and what prevents more severe complications. If there are ongoing contributing factors that can be modified to reduce disease severity or recurrence, those are discussed (or should be).
Now back to acne. Acne is a disease of pilosebaceous units, which are hair follicles in the skin with one or more sebaceous or oil glands that produce sebum. Where they open on the skin is the pore.
Acne happens when the pilosebaceous unit gets plugged, trapping bacteria and sebum leading to inflammation. The result can be blackheads or inflammatory lesions (papules and pustules—commonly known as pimples). These lesions can lead to scarring.
There is no singular root cause of acne, rather there are several mechanisms that contribute to acne:
Sebum production: Sebum is the oily, waxy substance produced by sebaceous glands. It tracks up and out onto the skin where it plays an important role. Some people produce more sebum or their sebum is thicker or more friendly to bacteria. Excess or thick sebum can block pores, trapping bacteria.
Altered keratinization: The process by which skin cells develop and fill with the protein keratin. When this is altered, this can lead to plugging of the pores, trapping bacteria and sebum. It may also affect inflammation.
Amount and Type of Bacterial colonization: We all have bacteria on our skin. The main bacteria involved in acne is Propionibacterium acnes.
Inflammation in and around the sebaceous unit: The degree and type of inflammatory response to the trapped sebum and/or bacteria.
Each one of these four mechanisms can be affected by many factors including genetics, environment, stress, and hormones, to name a few. Plugging of pores, hence trapping bacteria and sebum, can also be caused by facial products. Smoking is definitely related to acne, but the exact mechanisms aren't known. How we are colonized with bacteria can be related to many factors, where we live, what we eat. The immune system can be affected by sleep, diet, even childhood trauma.
Basically, it’s complicated. In medicine, we will identify the factors that can potentially be modified, for example skin care products, smoking, and stress. This is preventative care. But keep in mind that stopping products, quitting smoking, and stress management won’t reverse the inflammation or open blocked pores or kill the bacteria or immediately change sebum production. To do that, meaning to treat the acne, requires medications.
In the naturopathic model is the root cause of acne the bacteria? The inflammation? The sebum? The keratinization? Or is it the genetics affecting sebum production or the genetics affecting inflammation? If it’s genetics, is it the gene, or how the gene is expressed? What about diet?
Humans love heuristics, boiling something down to a simple cause or two, but the truth is most medical conditions are multifactorial. If there were an easy answer we’d have it.
In medicine, we don’t speak of the root cause, we speak of mechanisms (or hypothesized mechanisms if unknown). With acne we know there are 4 basic mechanisms, but it is possible over time with more research we could discover more. And in medicine we speak of treatment as well as preventative care.
So let’s get back to oral contraceptives and acne. They most definitely work. This is because hormones are involved with acne. Testosterone increases sebum production, which is why acne is linked with puberty as this marks the onset of testosterone production for both men and women. This is also why during puberty boys often have more acne or worse acne than girls. The estrogen in birth control pills increases the amount of sex hormone binding globulin (SHBG), a carrier protein that binds estrogen and testosterone. SHBG binds testosterone more strongly than estrogen (I think of this as testosterone pushing estrogen out of the way for a seat on the bus). So more SHBG means more bound testosterone and bound testosterone is inactive and can’t impact sebum. The estrogen in birth control pills also reduces the production of testosterone by the ovary and adrenal gland and may directly impact the sebaceous gland in other ways.
Only contraception with estrogen is helpful with acne, as the progestin (the other hormone and the hormone in the IUDs, the DepoProvera shot, and the implant) can sometimes act like a testosterone on tissues, so progestin-only contraceptives can worsen acne. The progestin in the pill does not negate the impact of the estrogen. The benefit from the pill is well established and the choice of pill doesn’t seem to matter — it’s about the estrogen.
So why doesn’t the pill work for every woman with acne? Not every therapy works for every person. It is also possible there is more than one mechanism causing a person’s acne, and so if only the pill is tried the effect will be minimal. Think of the four main mechanisms as locks on a door—if only one lock is unlocked, you can’t get through the door. So someone may also need a topical cream or antibiotic to kill bacteria and/or impact abnormal keratinization.
But what about those people who say the pill is risky?
Every medication has risks and benefits and untreated acne can lead to depression and have serious long lasting consequences for many people. Topical benzoyl peroxide, an effective treatment of mild acne (kills the bacteria, but may also affect keratinization and inflammation) can irritate the skin. Topical retinoids (works on keratinization, inflammation, and bacteria) can be too irritating for some to use. Oral antibiotics (kill bacteria and reduce inflammation) can lead to antibiotic resistance or diarrhea. Isotretinoin (Accutane, works on all four mechanisms that cause acne), but can affect the liver and must not be used during pregnancy.
Birth control pills are associated with a very small risk of blood clots (less than pregnancy and significantly less than the postpartum period) and while there is a very low risk of breast cancer that goes away over time when the pill is stopped, the pill also lowers the risk of ovarian and endometrial cancer and that reduction does not go away when the pill is stopped. The risk of depression related to the pill may be 1 in 200 for teens. However, all things considered, with the pill there is a net positive for life expectancy.
So whether oral contraception is started for acne will depend on the risks and benefits of all the other therapies as well as the severity of the acne and the need to be on the birth control pill for other reasons. For example, someone trying to decide between the pill and the IUD for contraception who has acne might prefer the pill. Then again, she might prefer the IUD and to treat her acne with other therapies. No treatment is given in a vacuum.
Post pill acne emerges because a treatment was withdrawn. It’s not caused by the pill, it’s the result of stopping therapy. And acne may not return after the pill is stopped or if it does it may also be milder and be well-managed with a topical therapy.
The birth control pill with estrogen is highly effective for acne and instead of root causes, think of mechanisms and contributing factors. It may be less satisfying, but it is more accurate.