When it comes to acne, the back is often forgotten. That makes sense—it’s not something you regularly see with your own eyes, it’s hard to reach on your own, and it’s usually covered under clothes. Even doctors who specialize in acne haven’t given back acne as much attention as it deserves, says James Del Rosso, D.O., adjunct clinical professor of dermatology at Touro University Nevada in Henderson, Nevada and an Acne Store advisory board member. “Most of the studies on various acne medications have traditionally focused on treating the face,” Del Rosso explains. Thankfully, he says that’s changing, and that physicians are now giving “bacne” the attention it deserves. And knowing the cause of your back breakouts is the first step in addressing how to get rid of it effectively. Here, Dr. Del Rosso outlines the common culprits.  

1. The wrong workout wear can cause back acne

That snazzy athleisure look may rack up the likes on Instagram, but it could be exacerbating your acne. Combining sweat with friction from workout equipment and non-absorbent clothing is an equation for pimples caused by widespread friction, including the back, chest, and shoulders. “It creates the ideal conditions for breakouts to develop and can even irritate the acne that’s already there,” says Del Rosso. Instead, he’d like you to opt for clothing made from moisture-wicking fabrics like cotton to keep sweat from sitting on the skin and contributing to clogged pores. Also important: Be sure to disrobe as soon as you’re finished with your workout and hop in the shower. A workout session done wrong easily leads to a sudden back acne breakout.

Up to 60% of patients with facial acne also have truncal acne on the back, chest, shoulders, or arms.

2. Letting your bacne go untreated

According to Del Rosso, up to 60% of his patients with facial acne also have truncal acne on the back, chest, shoulders, or arms. “They’re not necessarily going to tell me that, but it doesn’t mean they’re not bothered by it and they don’t want treatment,” he adds. “And if you don’t look, it can be easily overlooked.” And unaddressed acne may only make matters worse. Treatment can be a bit more difficult—there’s a wide surface area to cover and a chance products and medication may not be applied correctly—but a consistent regimen is key to addressing breakouts anywhere on the body.  

3. Excess iodine in your diet

Foods like seaweed, cottage cheese, eggs, and seafood are rich in iodine, a trace mineral that’s not produced by the body and is important in the healthy functioning of your thyroid. Ingest too much of it, though, and it may be a cause of acne, says Del Rosso. So how much iodine is too much? The FDA recommends taking about 150 micrograms daily. To put that in perspective: An egg has about 24 micrograms; a cup of cottage cheese has 65 micrograms; three ounces of cod contains about 80 micrograms; and Kombu kelp can have a whopping 2,900 micrograms in one sheet. If you’re suffering from back acne and body breakouts, talk to your dermatologist about keeping tabs on your iodine intake.

4. Certain medications can cause back acne flare ups

It’s no secret that hormonal fluctuations can lead to acne, so taking medications that tinker with your body’s delicate balance of hormones can be an issue. “If a person is ingesting anabolic steroids because they want to pump up, they can get acne that’s more severe and in a lot of different areas on the body other than the face,” says Del Rosso. The testosterone in hormone therapy can also have an effect. In addition, some birth control—both implanted devices and ingestible medication—have ingredients that are androgenic, a type of hormone effect that’s similar to testosterone and may contribute to acne.