Board-certified dermatologist Tiffany Libby, M.D., says they may be round or oval-shaped, but moles can come in all different shapes and sizes. She also notes that the peak time for new moles to appear on the skin is during your 20s and 30s, but overall, the development of moles is normal. Libby agrees and says these oval-shaped brown spots occur only on sun-exposed skin and are not present at birth. “Freckles can come and go but usually start appearing as early as the first few years of life,” she says. So just when you find yourself desperately wishing you had freckles all over your face, think again. These spots are caused by sun exposure and pigment transfer to the skin cells called keratinocytes. It’s also important to note that freckles can only appear on the parts of the skin that get direct access to the sun. Even though freckles are benign, they are a direct result of unprotected sun exposure. “Freckles indicate that you’ve had sun exposure and damage, and we know that sun exposure leads to photoaging like brown spots and wrinkles, as well as skin cancer,” Libby says. “Freckles are a good reminder to wear your sunscreen and keep your skin protected as much as possible from the sun.” And yes, anyone can get freckles, no matter how light or dark your skin tone is. Hartman also adds that if a patient has a family history of melanoma or is red-headed, blue-eyed, or fair-skinned, any new or changing growths should be evaluated by a board-certified dermatologist. You want to make sure you keep an eye out for this regularly, too. “I always tell people to party in your birthday suit on the date of your birthday and look for any ‘uninvited guests,’” she says. “The more consistently you check your skin, the more likely you are to catch a precancerous or cancerous spot early, when it can be more readily treated. And when in doubt, make an appointment with a board-certified dermatologist.”