Could it be the extra junk food you’ve been eating as a result of the stress? Or maybe you’ve been in the sun too much? Point is, there are a lot of myths surrounding pimples. We looked at the research and talked to leading experts to uncover these five surprising reasons your skin may not be as smooth as it could be.


A study published the Journal of the American Academy of Dermatology found that boys who had two or more servings of milk a day were the most likely to have acne. Researchers believe this applies to older men, too.

“Milk contains many biological products apart from protein and nutrients, like insulin growth factor-1, which is similar to insulin, and alpha reduced sex hormones,” explains study author Clement Adebamowo, M.D., professor at the University of Maryland. “These molecules are designed to enhance the growth and development of the calves, which can cause a biological response in the person who drinks it,” he says. One response: Increased sebum production, an oily substance that can clog pores. Researchers aren’t sure why some people have this reaction while others are fine.

Just one cup of milk can cause breakouts, says Adnan Nasir, M.D. and Men’s Health dermatology advisor. If you break out frequently, opt for almond milk, instead. Try this for 2 months and see if it makes a difference, Dr. Nasir recommends.


Researchers gave young men a face cleanser and assigned them to one of two 12-week diets: Either an eating plan high in carbohydrates, or one high in protein, vegetables, and whole grains. Though both groups saw a decrease in the number pimples, the high-protein subjects had double the drop.

The researchers believe increased insulin can cause inflammation in the skin, leading to breakouts, but more research still needs to be done. “Processed foods could be another factor,” says Alan Aragon, M.S. and Men’s Health nutrition advisor. Lay low on the sugar and switch to whole grains to be safe (solid advice for even smooth-skinned men).

Not Enough Omega-3s

A 250 mg supplement of EPA—the kind of omega-3 found in sardines and anchovies—reduced the number of pimples in a study published in Lipids in Health and Disease. The total lesion count among five people dropped from 63 to 40 after 2 months, presumably because of reduced inflammation.

“Inflammatory chemicals increase the production of sebum,” says study coauthor Alan Logan, N.D., an independent researcher. Omega-3s prevent these chemicals from making sebum, which is known to cause acne, he says.


Researchers believe that stress hormones can worsen acne. Certain steroid hormones, like glucocorticoids and adrenal androgens, are released during stress, and are known to cause breakouts by activating the oil gland and clogging your pores, according to researchers at the Stanford University. A Stanford study even found that college students had more acne during exams, when they reported more stress. (Researchers controlled for changes in sleep and diet.)

Too Much Sun

“Over several years, sun exposure may increase your skin’s oil production, which clogs your pores,” says Dr. Nasir. If you’re fair-skinned, only 5 to 10 years living in a sunny climate as an adult can make you more susceptible to acne.

We’re not telling you to leave your home on the beach, but choose your sunscreen wisely. “The actual sunscreen doesn’t clog pores,” says Dr. Nasir. “It’s the liquid it’s dissolved in.” Choose spray-on sunscreen, which is dissolved in alcohol instead of plant oils like palm oil. “The alcohol will evaporate and only the protection is left behind,” he says.