Search “makeup tutorial” online, and you will get 343 million hits. Click any one of the links, and you are likely to land on a lesson involving dozens of steps and scores of products. In this Instagram age, wearing an elaborate “full face” has been normalized. But could there be consequences for our health? The answer is yes, some caused by the cosmetics themselves and some by how we use — and misuse — makeup.

Eyes are most at risk

Makeup causes more problems for our eyes than our skin. Let’s take them from least to most severe: Wearing mascara and eyeliner can cause your eyelashes to thin, especially if your chosen products are drying and you don’t wash them off thoroughly. Sleeping in mascara and other makeup can even cause it to clog the glands under your eyelids. A case study in the journal Ophthalmology shows gruesome photos of black nodules that formed under a woman’s eyelids after she failed for years to wash her mascara off properly.

On the other hand, over-scrubbing could knock eyelashes out or upset the natural microbiome of your eye area. “You have good and bad bacteria on your eyelids,” explained ophthalmologist Shilpa Rose of Whitten Laser Eye in Chevy Chase, Md. “If you scrub too much, you can remove the good bacteria, which is actually protective.”

Rose specializes in treating dry eyes and said makeup can also interfere with the meibomian glands, located on your lash line, that produce the oil that is supposed to lubricate your eyes. Wearing eyeliner inside your lash line can be particularly problematic if you don’t wash it off thoroughly. “I do not believe it’s the makeup,” Rose said. “It’s the makeup hygiene.”

Speaking of hygiene, Rose said we should never share makeup with others, which can spread eyelash mites, called Demodex, as well as pinkeye and other eye infections.

New York City ophthalmologist Cynthia MacKay said eye infections can be more than just passing inconveniences. She vividly remembers one patient who suffered a more permanent scenario. “A contact lens wearer who wore makeup but did not replace it regularly developed a corneal ulcer with central scarring and decreased vision,” MacKay said.

MacKay said “operator error” is part of the problem because consumers tend to keep cosmetics and applicators around for far too long. A study published last year in the Journal of Microbiology found that up to 90 percent of used cosmetic products donated by product users in the United Kingdom were contaminated with bacteria, including E. coli and Staphylococcus aureus.

These bacteria can gain entry to the innermost parts of our eyes through other beauty accidents — anything that scratches the cornea. Rose has seen it all in her patients. “I’ve had a curling iron to the eye, mascara brush to the eye,” she said. One patient mistook her nail glue for eye drops. “The glue basically peeled off her cornea,” Rose said.

Rose also warns about the danger of using glitter near your eyes. She’s not referring to shimmery makeup, but actual glitter applied to the face, a trend in recent years. Glitter is hard to flush out of the eyes and can tear and scrape them. One woman lost her left eye to glitter injuries and documented the entire tragedy in a series of blog posts.

MacKay said we can be our own worst enemies when it comes to makeup. “During 40 years as an ophthalmologist, I have seen many more eye problems in women than in men, caused by eye makeup,” she said.

Pros and cons for the skin

After that doom and gloom, how about a bright spot? When it comes to your skin, wearing full-face makeup actually has one health benefit: It acts as a rudimentary sun block, even if it doesn’t contain official SPF ingredients. “Mineral-based makeups provide more protection from the sun than other makeups,” said Eric Finzi, medical director of Chevy Chase Cosmetic Center. “Clay-based foundations, if applied thickly enough, also help protect the skin.” Finzi spent two years researching skin cancer causes and treatments at the National Cancer Institute. He said it’s even more effective to apply a mineral-based sunscreen followed by mineral makeup. If your makeup contains retinoids, which have been proven to reduce fine lines, wearing it could even reduce or delay wrinkles.

Unfortunately, although makeup can help block the sun, it can also block your pores. “For people who are acne-prone, worsening of acne is a big problem,” said Elizabeth Tanzi of Capital Laser and Skin Care in Chevy Chase. “Even non-comedogenic products can cause trouble if not removed daily,” she added. “Non-comedogenic” is dermatologist-speak for products that won’t block your pores — only they will, if you don’t wash them off properly. Once again, how we manage our makeup matters.

As a news anchor at KMPH, in Fresno, Calif., Kim Stephens has to wear full-face makeup as part of her job. However, after 32 years, she has suffered no ill effects that she can see. “I never worried about the long-term effects of makeup,” Stephens said, “because every day, once I get home, I wash my face very well to get the gunk off.”

Thorough removal is important to keep makeup from drying out the skin. If you have naturally dry skin, the zinc and titanium often used for sun protection in foundation can dry your skin out even more. “Heavy makeup use is on the rise due to social media,” Tanzi noted. “Prevent problems by cleansing it all off at night.”

Tanzi recommends a double cleanse for anyone who wears a lot of makeup. “The first cleanser should be a balm to help emulsify and break down all of the tenacious ingredients in makeup,” she explained. The second should be a traditional cleanser to completely remove the balm and emulsified makeup. However, once again, over-cleansing can disrupt the body’s own natural oils. For that, Tanzi recommends “makeup holidays” to give your skin time to rebalance itself.

Are cosmetic chemicals a concern?

Joce Sterman takes makeup holidays for a different reason. She’s an on-air investigative reporter for Spotlight on America. “I became most concerned after this piece I did last year, which looked into how products like cosmetics are barely regulated,” she wrote in a Twitter direct message. “FDA guidelines haven’t been updated since Roosevelt was president.” The United States prohibits the use of 11 ingredients in cosmetics. By contrast, the European Union has banned more than 1,000. “Any woman who wears makeup to the extent TV personalities do should at least be thinking about long-term effects,” Sterman wrote.

It’s hard to know whether some of the ingredients in cosmetics are harmful because it’s hard to know what those ingredients are. Makeup manufacturers don’t have to disclose ingredients they consider trade secrets. But occasionally, we get a glimpse. Last year, the FDA warned consumers that it had found asbestos, a known carcinogen, in a handful of makeup products. 

Sens. Dianne Feinstein (D-Calif.) and Susan Collins (R-Maine) have introduced legislation to strengthen oversight of makeup. The Personal Care Products Safety Act would require the FDA to study the safety of at least five ingredients per year for use in cosmetics and would give the agency the power to recall products deemed unsafe. Major cosmetic companies support the bill, which would give them rules of the road. However, despite bipartisan support, the Senate has not passed it.

For now, just as consumers need to take responsibility for tossing their old mascara and washing their filthy brushes, we must take our own steps to sidestep potentially hazardous chemicals in our makeup.

If you are worried about the chemicals in cosmetics, consult the Environmental Working Group’s Skin Deep database, which rates specific cosmetics on their chemical content. On the go, you could carry EWG’s wallet guide, which lists a dozen key ingredients to avoid. Alternatively, you could purchase your cosmetics at stores that have done some of the work for you. Whole Foods has banned more than 100 ingredients from its cosmetic products. Target vowed to exclude key chemicals of concern from all beauty products it sells by 2020. CVS and Rite Aid also pledged to remove certain ingredients by this year, but only from their store brands. Walgreens will implement a restricted-substances list for its store-brand beauty products by the end of 2021.

Regardless of the chemicals in your products, experts give this general advice for safer makeup use:

Do:

●Wash your face thoroughly but gently every night, using the “double cleanse” method if needed.

●Wash your hands before applying cosmetics.

●Check to see if your makeup has an expiration date; if not, write your own based on the purchase date.

●Replace eye makeup every three months, according to the American Academy of Ophthalmology. Replace other makeup as often as you can afford to. Side benefit: It will also work better.

●Use disposable makeup applicators or wash or replace your makeup applicators often.

●Use extra caution if you are immunocompromised.

●Take makeup holidays to let your eyes and skin rebalance.

Don't:

●Sleep in your makeup.

●Over-cleanse your face.

●Apply makeup inside your lash line.

●Delay seeing a doctor if you have a “foreign body” sensation in your eye.

●Share makeup or makeup applicators.

●Sample makeup at stores; if you must, use a one-time applicator.

●Keep makeup near the toilet, where microscopic mist can contaminate it.

●Apply cosmetics in moving vehicles.

●Keep makeup in hot places, such as your car, where bacteria can build up faster.

●Apply glitter near your eyes.

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