It’s a common image in movies and television: a person undergoing cancer treatment and losing their hair. This powerful visual has created a strong link in our minds between radiation and hair loss. But is this always the case? The relationship is more specific than you might think.
Radiation itself is a broad term, but the type that causes hair loss is almost always therapeutic radiation, used as a targeted treatment for cancer. It’s not the kind of exposure you get from an X-ray or a flight. The key thing to remember is that this hair loss is typically not permanent when it happens, and it’s usually confined to the specific area being treated.
Why Radiation Treatment Affects Hair Follicles
Radiation therapy works by targeting and destroying rapidly dividing cells, which is a hallmark of cancer. Hair follicle cells also divide very quickly to make your hair grow. When the radiation beam passes through the skin to reach a tumor, it can’t always tell the difference between the cancer cells and the healthy, fast-growing hair cells in its path. This damage to the follicles is what causes the hair to fall out.
It’s All About Location and Dose
You won’t necessarily lose all the hair on your head. Hair loss, known medically as alopecia, only occurs in the area where the radiation is aimed. For example, if you are receiving radiation to your hip, you will not lose the hair on your head. You might, however, lose hair in that specific patch of skin. The dose of radiation also plays a big role. Higher doses are more likely to cause hair loss, and it may be more difficult for hair to grow back afterward.
What to Expect If You’re Receiving Treatment
If your treatment plan involves radiation to the head, your care team will discuss the likelihood of hair loss with you. It usually begins two to three weeks after your first session. The hair may thin gradually or come out in clumps. It can be an emotional experience, but being prepared can help. Many people choose to cut their hair short beforehand or find a wig or comfortable head covering they like. The good news is that for most people, hair begins to grow back a few months after treatment ends, though the texture or color might be slightly different at first.
Caring for Your Scalp During Treatment
Being gentle with your skin and any remaining hair is important. Use a mild, fragrance-free shampoo and pat your scalp dry instead of rubbing it. Protect the area from the sun with a soft hat or scarf, and avoid using harsh chemicals, dyes, or hot styling tools. Your medical team can provide specific product recommendations that are safe for sensitive, treated skin.
While radiation-induced hair loss is a well-known and very real side effect of certain cancer treatments, it’s important to know that it is usually a temporary part of the journey. The focus is always on healing, and for most, the return of their hair is a welcome sign of recovery.