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Multivitamins. They're likely not necessary for healthy people who have no vitamin deficiencies, says Melrose. And some supplements can actually cause health problems if consumed in excess amounts, he says. For instance, too much vitamin A can cause liver damage and too much vitamin C can cause kidney stones and diarrhea, according to the U.S. National Library of Medicine.
What to use instead: If you have no deficiencies, just eat a well-rounded diet that includes whole foods like fruits and vegetables. Exceptions: Pregnant women should take prenatal vitamins to prevent birth defects, says Melrose, and people who are nutrition-deficient can benefit from supplements recommended by a healthcare professional.
Douches. Douching—washing the vagina with water or other fluids—isn't necessary and can actually be harmful. That's because douching can upset the vagina's normal balance, making you more susceptible to infection or irritation, according to the American Congress of Obstetricians and Gynecologists (ACOG).
What to use instead: Nothing—the vagina cleans itself, says ACOG. But if you notice a change in discharge or unpleasant odor, make an appointment with your health practitioner. It could be a sign of infection.
Scented feminine products. Like douches, scented tampons, sprays, and pads can do more harm than good, potentially leading to infection and vaginal irritation.
What to use instead: Unscented feminine products, advises ACOG. To stay fresh and maintain vaginal health, wash only outside the vagina with mild soap and plain warm water—or warm water alone.
Some cold-prevention remedies. Runny nose? You can probably skip the echinacea and vitamin C, says Melrose: Studies on their effectiveness have been inconclusive. And take care with zinc-based nasal sprays. They can stifle your sense of smell, perhaps permanently, according to the Mayo Clinic.
What to use instead: "It's better to just wash your hands during cold and flu season," says Melrose—using regular soap, of course.