What to consider: There's no problem with using a face lotion on your body―except that it will be pricier than one for the body. Manufacturers use better-quality (and more expensive) ingredients to care for the delicate skin on the face. Using a body lotion on your face, however, could dry it out or irritate your skin. "Since the body's skin is tougher and thicker than the face's, it can handle more chemicals that are usually found in body lotions," says David Bank, director of the Center for Dermatology, Cosmetic & Laser Surgery, in Mount Kisco, New York.
Bottom line: It's fine to use one lotion for both in a pinch, but it's best to use separate products in the long term.
2 of 10Beth Adams
A Night Cream and a Day Cream?
What to consider: Dermatologists agree that your skin won't be harmed by using a night cream during the day or a day cream at night. However, night creams do tend to be thicker, which can make skin look greasy if worn during the day. Also, some anti-aging ingredients found in night creams, such as retinol, are broken down by ultraviolet rays and won't be as effective in the sun. If you're going to use a daytime moisturizer overnight, choose one without an SPF, since added sunscreen ingredients can cause irritation or breakouts.
Bottom line: If you want just one face cream, go with a lightweight lotion and apply a separate sunscreen over it during the day.
3 of 10Beth Adams
Body Wash and Bubble Bath?
What to consider: Bubbles look pretty in the tub, but they're not great for the body. The added detergents that help bubbles form may dry your skin if used as an everyday cleanser. "Unless you really want that bubble-bath experience with candles and relaxing music, I'd stick to cleansing with body wash," says Jamie Ahn, owner of Townhouse Spa and Acqua Beauty Bar, in New York City. If you are craving a soak in the tub, it won't hurt to pour some body wash in, but you won't get the same concentration of bubbles.
Bottom line: Use body wash for both the shower and bubble baths―if you can live with fewer bubbles.
4 of 10Beth Adams
Hand Cream and Foot Cream?
What to consider: The skin on hands and feet is similarly thick and dry, so these products are largely interchangeable. Ingredients like peppermint oil and tea-tree oil are often added to foot creams as natural deodorants. They won't hurt hands but will give them a minty scent and sometimes a tingly feeling, and they could hurt your eyes if you rub them. It's fine to use hand cream on your feet; you just won't get any deodorizing effect.
Bottom line: If you like a product's feel and scent, go ahead and use it on both hands and feet.
5 of 10Beth Adams
Self-Tanner for the Face and for the Body?
What to consider: Because self-tanners can be drying, cosmetics companies often put heavy moisturizing ingredients in products for the body, which could clog pores and cause breakouts on your face. Self-tanners for the face are safe to use on the body, but because they tend to come in much smaller packages, you may not have enough to cover your entire body or achieve the color you want.
Bottom line: Use separate self-tanners, or look for one that is marked for both face and body.
6 of 10Beth Adams
A Clear Topcoat and a Base Coat?
What to consider: When you're applying polish, a base coat serves as an adhesive between the color and the nail. A topcoat provides shine and prevents chipping but does not have that adhesive effect. If you want something that does it all, look for a multipurpose clear coat that is labeled for use as both a base and a topcoat.
Bottom line: If you simply want shiny, natural-looking nails, use a topcoat and lose the base coat. If you're applying colored polish, use each for its intended purpose.
7 of 10Beth Adams
Cotton Balls and Cotton Pads?
What to consider: Both shapes perform the same functions, such as helping to remove makeup and nail polish. "Cotton pads give you more of a surface, so you can use fewer of them, and they shed less of the fiber," says Joanna Schlip, a makeup artist in Los Angeles. Cotton balls are typically thick and absorb more liquid. All the experts agree that it comes down to a matter of personal preference.
Bottom line: Choose one―they do the same thing.
8 of 10Beth Adams
Eye-Makeup Remover and Face-Makeup Remover?
What to consider: Proceed with caution when using a basic makeup remover (meant for the face) in the eye area. "Stick to a product that has been ophthalmologist-tested to prove that it's safe around the eyes," advises Audrey Kunin, an assistant clinical instructor of dermatology at the University of Kansas School of Medicine. If you have only eye-makeup remover, avoid swiping it over your whole face, as these products typically contain oils that could clog pores.
Bottom line: If your regular cleanser removes makeup and is gentle enough to use around the eyes, stick with that and ditch the separate products. Otherwise, use each for its intended purpose.
9 of 10Beth Adams
Eau de Toilette and Eau de Parfum?
What to consider: "The intensity of essential oils is greater in eau de parfum than in eau de toilette," says Mary Ellen Lapsansky, executive director of the Fragrance Foundation, in New York City. Since eau de parfum is heavy on oils and light on alcohols, it will last longer on your skin―and also cost more. (Eau de cologne is actually the least concentrated of scents but can be used interchangeably with eau de toilette.)
Bottom line: You need only one. Choose based on your desired level of intensity (and price range).
10 of 10Beth Adams
Depilatories for the Body and for the Face?
What to consider: Body hair is thicker and tougher to remove than facial hair, so waxes and depilatory creams for the body have stronger formulas than do those for the face. If you use a facial depilatory on your body, it won't work as well, and a body depilatory cream could irritate the skin on your face. The eye area is particularly sensitive, so if you want to remove eyebrow hair, stick with kits designed for that.
Bottom line: Invest in different hair-removal products.