“If you have oily scalp, then daily washing is needed,” she explains. “Sometimes, people think they have dry scalp because they have dandruff, but in those situations, more frequent washing is also helpful.”
People with oily hair or who use products regularly will likely need to wash more frequently than those with drier hair or who do not tend to use products in their hair.
Most people should wash their hair when it becomes oily, dirty, or when a lot of product has built up on the scalp. The American Academy of Dermatology Association (AAD) notes that: If a person has oily hair, they may want to wash it daily. If a person has chemically treated hair, they may want to wash it less often.
Washing your hair every day contributes to an oily buildup. The more you clean your hair, the more oil your scalp produces to compensate. If you normally wash everyday, it'll take time to get used to washing it less. So start by going an extra day or two in between your normal washes.
Those with fine or thin hair, however, may find their hair looks greasy after just one day. It's all to do with the amount of oil your scalp produces, as well as how well your hair can carry that oil.
You can tell you're using too much shampoo if the product feels like it's coating your hair and is difficult to lather. If you're worried that your shampoo isn't doing a good enough job at cleaning, it may be time to switch to a deep cleaning shampoo that works.
Get healthier hair
The folks who don't wash their hair for months on end claim that when they stop washing, their hair eventually produces less scalp oil, which is called sebum. The result: hair that's shiny, moist and healthy ' never greasy.
The short answer is yes! The slightly less short answer is that an oily scalp definitely contributes to hair loss but is often not the sole cause of it. Excess amounts of oils can trap and attract dirt, dandruff, and product build up, which clogs pores and prevents new hair growth.
“Shampooing your hair twice is beneficial because it allows for proper cleansing, giving you longer periods of time with a clean scalp and keeping away the oily hair problem,” he says. “It also keeps you away from over-shampooing your hair, which is a mistake that most women make.”
“If you have oily scalp, then daily washing is needed,” she explains. “Sometimes, people think they have dry scalp because they have dandruff, but in those situations, more frequent washing is also helpful.”
"You can train your scalp to be less greasy in the course of three to four days, however, it will take some time for your body to fully adjust," Potempa says. "Take some time to do research about the type of hair you have and establish a new routine that gives your body enough time to adjust to the change."
While you may be focused on your hair, your scalp is still skin. It's affected by hot water the same way as your body, which means that hot water can lead to dehydration. When the skin becomes dehydrated, oil production can increase to compensate leading to that greasy feeling.
As a rule of thumb, fine hair requires about a nickel-sized amount of shampoo, while those with thicker textures should use roughly two quarters worth of shampoo. If your hair is somewhere in the middle, a quarter-sized amount is adequate.
Overwashing. One somewhat unexpected cause of oily hair is overwashing. That's right, it's possible to wash your hair too often. Every time you wash your hair with shampoo, it sends the scalp the signal to produce more sebum.
"Although sebum is good for the hair, too much can make your hair look slick and greasy. Common causes of oily hair are unhealthy eating habits, medications, improper hair care, stress, hormonal fluctuations, and change in weather."
Greasy hair is caused by an excess or build-up of sebum, the natural oils produced by our scalp to support our hair health. These natural oils help to support the outer layers of the hair and protect the delicate proteins inside.
"Some of us naturally produce more oil than others, which can lead to a greasy scalp," says Birnbaum. "If you have both an oily face and scalp, it's likely you are naturally oil-prone." Alongside genetics, Birnbaum says that oil production is also tied to hormones, stress, and (of course) humid weather.
Apply a clarifying shampoo or exfoliating product once a week. If you're a greasy hair sufferer, you're probably a dry shampoo junkie. Nothing is wrong with using dry shampoo, but if you tend to use a lot of it or other styling products, this step—which you can consider a hair reset—is imperative.
Oily hair isn't healthy or unhealthy by default. People with an oily scalp can have healthy hair or dry, brittle hair. Your hair needs oil to be healthy, but too much oil can lead to buildup on the hair and scalp. Oily skin may also contribute to a condition called seborrheic dermatitis.
Greasy hair after washing may be due to a person's hair care routine, an overproduction of sebum, environmental factors, or underlying health conditions. People may be able to stop hair from becoming greasy as quickly by using a gentle clarifying shampoo and lightweight, non-greasy hair products.