Think your nail-biting habit is only ruining your nails? Think again — and this time, think about all the surfaces your fingers come in contact with. Door handles, elevator buttons, MRT handlebars. All the bacteria that you’ve accumulated not only comes in contact with your face, you also ingest them while you’re chewing subconsciously on your nails. All you’re doing is pushing bacteria deep into the mucous membrane of your skin. If that isn’t enough to stop you from chewing your nails, we don’t know what will.

Sure, you may have washed your face before bed, but remember that the skin regenerates at night, so it will produce more sebum and get rid of grime while you’re asleep. And if you don’t change your pillowcases regularly, this means that dirt and oil from both your face and hair rub off on your pillow and transfer back onto your skin the following night. Um, gross.

A study showed that a phone is actually 10 times dirtier than a toilet seat. Again, think about your fingertips and where they have been while you’re happily sending a DM on Instagram. Studies have found serious pathogens on cell phones, including Streptococcus, MRSA and even E. coli. Wipe down your phone often and don’t take your phone where it doesn’t belong — like the bathroom.

While this is a pretty controversial debate, cutting dairy from your diet can help your acne issues. Dairy can be a huge acne culprit because it can stimulate oil glands, therefor increasing clogged pores. Cow’s milk contains hormones that can interact with your skin, as well as influence your body’s own hormones.

Good on you for making sure you’ve always got sunscreen on. However, some physical sunscreens behave as a barrier blocking sun rays, and in doing so, can cause you to sweat more underneath the product. The sweat then gets trapped and clogs your pores. Don’t stop using your SPF50, though. Simply stay away from physical sunscreens containing zinc oxide or titanium dioxide and get the chemical variety, which absorbs the sun rays as opposed to blocking them. Choose one that’s noncomedogenic too and check out our recommendations here.