How often should I wash my hair?

Dear Reader, 

Lathering up your locks every day may leave your hair feeling squeaky clean—but can also make it dry and prone to split ends. How often you should wash your hair depends on your hair type, lifestyle, and many other factors. That said, it’s generally a good idea to wash your hair once it feels greasy or unclean. 

What influences how quickly your hair gets greasy? 

Sebum is your body’s natural moisturizer. It's produced by sebaceous glands on your face and scalp. Hair gets greasy when sebum builds up. Some factors that can affect sebum production include: 

• Age: Younger people tend to have more active sebaceous glands. This is because they have higher levels of hormones known as androgens. 
• Hair length: Sebum comes from glands on the scalp and must travel down each hair strand to moisturize it. As such, hair tends to be drier at the ends compared to the roots. Longer hair also tends to get drier, compared to shorter hair. 
• Hair type: It’s more challenging for sebum to travel down coil-shaped strands of hair compared to straight hair. Coarse, curly, and kinky hair tends to be drier than straight, silky hair. 
• Activity level: Exercising and sweating heavily can lead to a buildup of sebum, sweat, and other debris on the scalp. 
• Genetics: Some people naturally produce more oil than others. 

Can you actually over-wash your hair?  

Shampoo removes sebum, sweat, and other debris from your scalp. However, washing your hair too frequently or with overly harsh shampoos can leave it looking dry and frizzy. Your scalp may also become dry, irritated, or itchy. Dry, brittle hair that’s prone to breakage or split ends can be a sign of over-washing.  

How can you care for your hair type?  

If you have fine, straight hair that gets oily quickly, it’s a good idea to avoid heavy shampoos that are hydrating or moisturizing. Instead, opt for “volumizing” shampoos that won’t weigh your hair down. You might also consider double shampooing. This involves using a deeper cleansing shampoo on your roots, followed by a milder formula for the rest of your hair.

If you have dry, textured, or curly hair, it’s best to use shampoos that promote moisture, hydration, or curls. Conditioners that contain protein-based ingredients like amino acids can also help to repair damaged hair, restoring its ability to retain moisture.

Additionally, chemical treatments, hair dye, and heat tools can damage the inner and outer layers of hair, no matter the texture, making it brittle and dry. Regardless of your hair type, a good rule of thumb is to shampoo your roots and condition your ends. Focusing shampoo on your roots helps to lift dirt and grime from your scalp, which is where sebum comes from. Keeping conditioner away from the scalp helps prevent greasy roots. 

What can you use to clean your hair? 

Shampoos often contain detergents like sulfates. If you find regular shampoos too drying, you might consider switching to sulfate-free shampoos that won’t strip your hair of as much oil.  

Another alternative is washing your hair with conditioner only, also known as co-washing. A gentler form of cleansing, it’s said to “balance” sebum levels by preventing an overproduction of oil after deep cleaning. However, this claim hasn’t been backed up by research. If you decide to give co-washing a go, it’s helpful to remember that conditioner isn’t strong enough to remove heavy buildup from the scalp. As such, you may want to alternate between co-washing and shampooing or use a clarifying shampoo occasionally to get rid of excess residue.

Apple cider vinegar has also become a popular home remedy for boosting hair health. While there isn't much research on the hair care benefits of apple cider vinegar, advocates suggest that its antimicrobial properties reduce itch and inflammation. Additionally, the acidic liquid may help to lower the scalp’s pH value, adding shine to your tresses and reducing frizz. 

So, how often should you wash your hair?

Generally speaking, it’s recommended to wash your hair once it’s greasy or unclean to the touch. For some people, that means washing every other day. For others, it could mean shampooing once a week.  

You may be familiar with the idea that washing your hair less often will “train” it to be less oily. Unfortunately, sebaceous glands are controlled by hormones. Therefore, oil production can’t be changed by hair washing routines. If you’re thinking of scaling back how often you wash your hair, dry shampoo may help to keep things looking fresh between washes. Brushing your hair also distributes oils throughout your hair, preventing greasy roots.

Hungry for more information on hair health? You might consider speaking with a dermatologist. They may be able to help you identify your hair type and offer tips on styling and caring for your hair.  

Hairs to a clean and healthy scalp!