I had heard that like toothbrushes, you should replace mascara every 3 months. But it wasn’t until my beloved mascara began irritating my eyes that I started to wonder why. Turns out that it isn’t just cosmetic manufacturers wanting to sell more products – you really should change mascara every 3 months.
Every time you apply that mascara wand to your lashes, then put the wand back into the mascara, bacteria are joining the party in the tube. You’re contaminating your mascara every time you use it. And although the preservatives in the mascara do their job at first, all the bacteria in mascara means they become less and less effective over time.
The moist, dark environment of the mascara tube is the perfect breeding ground for bacteria. Go check the ingredients in your mascara. The first one is water, right? The water is necessary to get the right formulation for a mascara that will glide onto your lashes. But water is exactly what bacteria need to grow.
Mascara and liquid eyeliner are particularly problematic, because unlike most water based products, you’re putting the applicator back inside the tube each time. This is why mascara and liquid eyeliner are the makeup products with the shortest shelf life, and why replacing mascara regularly is so important.
“97.9% of women use makeup after the expiry date”
But most of us continue to use our mascaras well past the recommended use by date. A study of female medical students in Brazil found that 97.9% of them admitted to using makeup after the expiry date. Mascara was the most frequently mentioned product.
The researchers in the Brazilian study trying to find out when to replace mascara found Staphylococcus aureus in 79% of mascara samples from the students, and Pseudomonas aeruginosa in 13% of their expired mascaras. The study doesn’t mention how far out of date the mascaras were.
However, another study shows the levels of microbial contamination after using mascara for just three months. In this study, 40 women used mascara every day for three months. At the end of three months, 36.4% of the mascara tubes contained microbial growth. These microbes were mainly Staphylococcus epidermidis, Streptococcus species, or fungi.
The authors of this study thought that using a mascara for three months was the outside limit. So if you’ve been wondering how often should you replace mascara, it’s probably sooner than you think.
So what’s the problem with microbes in mascara? Microbes are everywhere, right?
You apply mascara to your eyelashes, which are right next to your eyes. And I know I’m not the only one who’s stabbed themselves in the eye with their eyelash wand, or got a bit of mascara into her eye!
Pseudomonas aeruginosa is a kind of bacteria that can lead to infections in people. Scratching the eye with a mascara wand has led to severe eye infections and damaged vision. It’s rare, but it has happened.
Staphylococcus epidermis is another kind of bacteria that can cause serious health issues, and this one is even more problematic because it doesn’t respond well to antibiotics.
In healthy people, neither of these bacteria should cause too many problems. But for someone with a weakened immune system, it can be a big issue.
And even for a healthy person, these bacteria can cause irritation and even eye infections. No wonder my eyes were getting irritated when I applied out of date mascara.
So when should you replace mascara?
You don’t have to swear off mascara forever. But you do need to be sensible, and if you’ve been wondering how often to buy new mascara, you now know that it really should be every three months.
The FDA has guidelines on the safe use of eye makeup:
- Keep your eye makeup clean – don’t put the mascara wand or the liquid eyeliner brush down. Apply it to your lashes or lids, and put it straight back in the tube.
- Don’t share or swap eye makeup – even with your family or close friends.
- Don’t apply eye makeup in the car! Getting a scratch in your eye from the mascara wand can cause serious eye infection, and even damage your vision.
- Wash your hands before applying makeup.
- Don’t use mascara or liquid eyeliner if you have an eye infection. Get rid of any eye makeup you were using when you got the infection.
- If your eye makeup causes irritation, stop using it. If you’re getting continuous irritation, see your doctor.
- Don’t dilute dried up mascara to reuse – throw it away.
- Keep your makeup in a cool place. The car glovebox might be handy, but it’s not ideal.
As for me, I’ve started writing the date on my mascara tube, and putting a reminder into my phone so that I remember to replace it every three months.
Looking for a non toxic mascara replacement for your current masacara? Check out our Natural Mascara Cheat Sheet.
How often do you replace mascara? Have you ever had a reaction to out of date makeup? Share your thoughts in the comments below!