acneI’ve been writing about hormones for so long that, for me, finding the unusual or quirky hormones studies (like this or this) is what gets me excited. So, I often assume that’s what will get you excited, too.

I forget that it’s often the simple stuff I take for granted that many of you would really want to know about.

I was reminded of this yesterday when Bev, a Hormonology newsletter subscriber, asked me a few basic questions about her skin, such as why we tend to get acne right before our period.

And, worse, why we don’t grow out of acne break-outs as we get older the way you’d think we would the further we get from puberty.

Since this is such a common problem, I figured I’d address it today:

First of all, rest assured, if you get premenstrual acne flare-ups, you are not alone. In one 2001 study in the Journal of the American Academy of Dermatology, 44% of women surveyed complained of pre-period pimples.

And, get this: The survey revealed that women older than 33 had the worst break-outs! What a cheat, right? Just as we’re starting to fight the slow creep of fine lines, our zit population swells.

But, those self-reports in that study may have been a bit of an underestimate (the problem with self-reports is that they rely on our faulty memories and less than impartial answers).

In a 2004 study in the Archives of Dermatology where researchers actually studied a group of women’s faces over the course of two menstrual cycles, they discovered that a whopping 63% of women experienced a 25% increase in acne premenstrually.

So, what’s causing this increase in pimples on the days leading up to our period? Researchers have a couple of theories:

One thought is that a spike in testosterone mid-cycle during ovulation sparks a higher output of oil. And so it may be that this excess oil clogs pores–and we don’t see the ensuing pimples until about a week and a half later after they’ve had time to stew and finally erupt.

Another theory is that progesterone during the second half of our cycle causes inflammation in our skin due to water retention. This traps dirt in our pores and ultimately triggers the unsightly spots.

What can you do to prevent pre-period breakouts–or at least reduce them to a less annoying level?

Since the problem seems to be that somehow your hormones are leading to more clogged pores in the second half of your cycle, the key then is to cleanse your skin and exfoliate extra-diligently from ovulation to your period.

(As Bev astutely pointed out to me in a follow-up email, in the days leading up to ovulation in our Week 2, we may be letting our usually diligent cleansing regimen lapse a bit because we get lulled by the clear, smooth skin that high estrogen is bestowing upon us on those days.)

You may also want to step up your face-cleansing game during your Week 3 and Week 4. For instance, if your skin can handle it, you may opt to use a gentle facial astringent.

If you want something a bit more natural, look for a niacinamide gel (like this one from Lifelink). This is made from a blend of aloe and a B vitamin–and has been proven to work just as well as prescription clindamycin (a topical anti-acne treatment) in two clinical studies (this one and this one).

Major bonus for we gals over 35: Niacinimide gel also reduces the appearance of fine lines and age spots and improves skin tone and color, research shows. (As with any skincare product, try a test patch first to see how your skin handles it.)

Okay, so this wasn’t the most exciting Hormonology post I’ve ever written–or the sexiest–but if you struggle with premenstrual acne flare-ups, I hope you find it useful. If it helps you, let me know!

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