1. Hair Spray. You may have heard somewhere that it will help set your makeup, but it should NEVER be applied to your face because it contains lacquers and alcohol that will dry our your skin, causing your skin to become dehydrated and you to look older. Plus, hair spray has repellents in it that could irritate your skin, leaving it red and bumpy.
2. Deodorant. Just because it keeps your underarms from sweating through your shirt does not mean it should be swiped over any area of your face that might perspire in hopes of keeping your makeup from melting down your face. You want your skin to be able to breathe. It's doing what it needs to for a reason, and you don't need to stop it. If you want to learn how to keep your makeup in place when temperatures rise, read this.
3. Hair Color. If you color your hair regularly and want your brows to match, use a vegetable-based colorant or tinted brow mascara on your arches instead of your at-home hair color, since the formulas are less harsh. Box dye can be too irritating for the skin around your eye area and can even make your eyes burn and tear up.
4. Vegetable Shortening. Even though this can be applied to your body skin to help treat psoriasis, it's far too heavy for your face and may even clog your pores, leading to breakouts.
5. Shampoo. The same surfactants that clean your hair, stripping it of excess oil and dirt, are not the same ones that you should be cleansing your skin with. Shampoos are manufactured to clean and do things to your hair shaft, they're not designed to deal with the delicate molecules of your skin. If you washed your face with shampoo, it would end up being really dry and flaky.
6. Hair Serum. Just because a formula has the word "serum" on the label doesn't mean it's the same kind of serum that your skin can handle. You're trying to coat the hair shaft with different types of ingredients that you wouldn't normally use to treat fine lines or any other skin woes. Plus, a lot of them contain fragrances that can heavily irritate your facial skin.
7. Body Lotion. It would be nice to just slather on one lotion and be done with it, but body lotions should NEVER be applied to your face because they're usually a lot thicker and typically contain fragrances that might irritate your facial skin. On your face, you should always use something more gentle and delicate. Think of body lotions and creams like spackle — they're there to fill in lost moisture, not to target your facial needs like anti-aging.
8. Foot Creams. This is basically a no-brainer, but if you're desperate and only have a foot cream laying around, DO NOT put it anywhere near your face — even if you just have a tiny dry patch. They're just too rich, thick, and sticky to be applied to your facial skin. They're formulated to break down thick calluses on your feet and often contain chemical exfoliants at percentages that you would never want to use on your face.
9. Nail Polish. Trying to paint your face for a Halloween or costume party? This only belongs on your nails. It has acrylic molecules that will actually dry the skin out. So, if you're thinking about doing up your face for a theme party, only use paint designed for your face.
10. Acetic Acids aka Vinegar. Yes, you can apply vinegar onto your face as a toner, but it's better to get a toner that contains the ingredient instead of whipping a bottle out of your kitchen cabinet. Vinegar can lose water over time and become stronger, so if you use it on your skin, it can actually burn it if you don't know exactly how long it's been in your possession.
11. Mayonnaise. This ingredient is in a lot of DIY hair masks because it's hydrating TO YOUR HAIR. But it's not a good idea to put it on your skin because it's too acidic and too occlusive, meaning it doesn't allow your skin to breathe and can clog your pores. If you want to try any at-home facial masks, here are a few that are safe to whip up.
(All tips are via Dr. David Colbert, M.D., a cosmetic dermatologist in NYC and founder of Colbert M.D. products)