Plus, simple treatments to undo the damage
Dry hair is not a hair type—it's a condition that can be treated. Your first step: Find out what's stripping strands of their natural oils. We asked experts in the field to nail down some culprits, as well as simple treatments to nix dry, damaged hair for good.

1. The Weather
“Summer includes overexposure to the sun, swimming, and products with alcohol, which can all dehydrate hair,” says Remington celebrity stylist Richard Marin. "And with winter comes extreme cold followed by overheated indoors, which can make hair parched and dry."

2. Smoothing Treatments
Too many smoothing treatments done close together can leave your locks super thirsty. “These treatments work effectively to smooth out hair and make it luscious and dreamy, but if they are done too frequently, the buildup of protein on the hair causes it to become brittle,” says hairstylist Sylvia Vaught, who's also the founder of L.A.-based home blowout service Blow Me.

3. Hormone Changes
“Birth control pills, pregnancy, and menopause are all times of physiological shifts within the body that can have an adverse effect on the hair, including dryness and brittleness,” says Vaught. She recommends seeing your doctor to discuss treatment options.
4. Using the Wrong Shampoo
Not all shampoos are created equal: Vaught warns against using your man’s drying shampoo when yours runs out. “You would be better off rinsing your hair a few times with just water to remove some of the oil, rather than risk the stripping effects of a shampoo that is not right for you,” she says.

5. Brushing Hair When Wet
“Remember that hair is most susceptible to breakage when it is wet,” says Vaught. This won’t necessarily dry the hair, but it will leave the ends brittle and lead to breakage down the entire strand. Instead of brushing wet hair, use a comb with a bit of leave-in conditioner on it.

6. Daily Heat Styling
Whether it’s the dryer or flat iron, daily heat to the hair will strip the hair of moisture. “This causes quite a bit of unnecessary damage that can be avoided,” says Vaught. If heat is imperative, aim to keep the temperature below 400 degrees.

Source: Womenshealthmag.com