Top 5 Reasons Why You Shouldn't Exercise in Makeup, From a Dermatologist

Many exercise enthusiasts would not dream of heading to the gym or going for a run through a busy park without applying a touch of makeup.

Whether it's a bit of mascara or a full face of foundation, this beauty habit can be incredibly damaging for your skin, according to dermatologist Dr. Shari Lipner from Weill Cornell Medicine.

Dr. Lipner encourages her patients to practice a thorough skincare routine to ensure the skin is clean and nourished. She shared with Newsweek her five key reasons why she discourages anyone from wearing makeup for a workout.

Makeup Can Get Trapped and Clog Pores

The first reason why people should think twice before applying makeup before a workout session is that it can get clogged in the pores. This not only causes breakouts, but for some individuals, it can result in acne.

While acne can also be caused by numerous factors—including hormones, genetics and environment—Lipner notes that "wearing makeup while working out can definitely cause acne or make it worse."

She explained: "Normally when you sweat, your pores open and sebum is released. Sebum is an oil produced by sebaceous glands and it has several functions, including hydrating the skin, transporting antioxidants, and fighting bacteria.

"When makeup gets trapped in the pores, it causes the skin to become inflamed and the bacteria gets trapped. The heavier the product, the more likely it is to make acne worse. Heavy foundation would be the worst to wear before working out."

If makeup is the only cause for the person's acne, once they stop wearing it during exercise then the acne should improve thereafter.

Makeup Mixed With Sweat Can Cause Inflammation

It's not just wearing foundation that can be problematic. Eye makeup can also cause irritation when mixed with sweat during a workout.

"When eye makeup mixes with sweat, it can cause inflammation in the thin skin around the eye. It could be mascara, eyeliner or eyeshadow, any makeup that comes in contact with the eye area," said Lipner.

"This inflammation can then lead to conditions like eczema. People with eczema or dry skin are more likely to have irritation from their eye makeup, but it can happen to anyone."

Finding the perfect mascara can seem like an impossible task, but Lipner noted that a waterproof mascara should stay in place better than a regular one, which means it's "less likely to cause irritation." It isn't foolproof however and doesn't negate all the potential for irritation.

'Makeup Is Breeding Group for Bacteria'

On top of potential irritation and clogged pores, Dr. Lipner also pointed out that wearing makeup is more likely to trap bacteria. Factor in a sweaty workout, and bacteria can lead to some harmful infections.

"Makeup is a breeding ground for bacteria, and it can lead to some bacterial infections such as impetigo in cases. When makeup clogs the pores, it prevents the sebum from being released, and that normally washes bacteria away."

There are two types of bacteria that can get trapped in the skin. One is propionibacterium acnes. This can be found not only on skin, but also on the oral cavity, the large intestine, and in the external ear canal. Propionibacterium acnes plays a role in the development of acne.

The other type of bacteria is staph aureus, which is considered one of the most important bacteria to cause human disease. Although most staph aureus infections aren't serious, there is potential for serious complications, including abscesses, cellulitis, and in more extreme cases bloodstream infections or pneumonia.

"If makeup is clogging pores and the sebum cannot wash away that bacteria on the skin, bacteria like staph aureus gets trapped and may lead to impetigo," said Lipner. "This is something that's more likely to occur with heavier foundations rather than powders."

Don't Forget the Sunscreen

Another reason why working out in makeup is a bad idea isn't so much the effect of the makeup itself, but more what it tends to stop people from doing instead.

Getting ready can be hectic, and skincare routines seem to increase with every new product that's released. But one step that's often forgotten is one of the most important for the skin's overall health.

"When people wear makeup, they are less likely to spend the time putting on sunscreen, which may lead to sunburn and an increased risk of cancer," Lipner explained.

"I know people are usually pressed for time in the morning, but if they are spending time putting on makeup, they should also remember to take the time to put some sunscreen on first. If you are doing an outdoor activity, it's important to wear sunscreen to decrease the risk of any burns or cancer."

She added that most dermatologists recommend an SPF 30 product, but it's still important to be cautious of the sun's rays because no sunscreen will ever block it out entirely.

While some foundations might have a small amount of SPF in them, it's not enough for adequate protection. Not to mention, sunscreen and foundation mixed together means even more products to clog up the pores.

Excess Bacteria Can Aggravate Rosacea

Dr. Lipner also pointed out to the potential for makeup to irritate and exacerbate rosacea.

"Rosacea is an inflammatory condition that often causes blushing, broken vessels, and acne-like breakouts. The cause of rosacea is not well understood, but it's thought that exposure to bacteria exacerbates the condition.

"People with rosacea have sensitive skin, so when it gets irritated, it may lead to breakouts.

"As mentioned, when makeup clogs up the pores and the sebum can't be released, then subsequently there will be more bacteria on the skin," she explained.

While Lipner discouraged people from wearing makeup during a workout, she also noted that there was no life-long effects of choosing to do so. If someone really feels that they need to put some makeup on, they should just monitor their skin and be sure they're not noticing any unhealthy changes.

She told Newsweek: "There are no known long-term effects of wearing makeup. It's fine for people to wear makeup, as long as it's not irritating their skin or exacerbating any skin condition."