Riverdale star Lili Reinhart took to TikTok in January 2024 with an update on her health, revealing that she was diagnosed with alopecia. But what exactly is the illness, and how is she treating it?

What Is Alopecia?

Alopecia is a very common disease that causes hair loss. It “happens when the immune system attacks hair follicles,” usually on the head and face, according to the National Institute of Health.

“​​Hair typically falls out in small, round patches about the size of a quarter, but in some cases, hair loss is more extensive. Most people with the disease are healthy and have no other symptoms,” the NIH revealed.

Anyone can get alopecia at any age, but the disease is most common in a patient’s teens, twenties or thirties. There are “no obvious triggers” for alopecia, according to the NIH, but “emotional stress or an illness” can bring it on. People with other autoimmune diseases are more likely to develop alopecia.

While there is no cure for alopecia at this time, there are several treatments that can reduce the hair loss. These include corticosteroid creams or injections, contact immunotherapy with a chemical applied to the scalp or other medications.

Does Lili Reinhart Have Alopecia?

Lili revealed her diagnosis in a viral TikTok video on January 30, 2024. The video showed the actress sitting under a red light machine used to treat the skin condition. She lip-synced over an audio of a man saying, “I’m pushed beyond limits of what a person should be pushed to endure.”

Over the video, Lili wrote, “Was just diagnosed with alopecia in the midst of a major depressive episode.” In the caption, she added, “Red light therapy is my new best friend.”

@lilireinhart

Red light therapy is my new best friend. #alopecia #mentalhealth

♬ original sound – Sam Huberty

Red light laser therapy can be an effective form of treatment for hair loss, as it stimulates weakened hair follicles, according to the Center for Dermatology and Dermatologic Surgery.

Lili joins a slew of other celebrities who have been diagnosed with alopecia, including Ashley Tisdale, Tyra Banks, Jesy Nelson, Alessia Cara and more. Jada Pinkett Smith has famously been battling the condition for years, first opening up about it in May 2018.

“I was in the shower one day and had just handfuls of hair in my hands and I was just like, ‘Oh my god, am I going bald?'” the Madagascar star, who shaved her head after she got her diagnosis, said on an episode of Red Table Talk. “That’s why I cut my hair, and why I continue to cut it.”

Lili Reinhart Has Been Candid About Her Mental Health

Lili has long been an advocate for mental health and has been candid about her experiences with depression. In May 2021, during Mental Health Awareness Month, she opened up about feeling “defeated” by depression at times.

“It’s an exhausting battle that I’ve been fighting for 11 years and some days, like today, it can feel intolerable,” she said on her Instagram Stories. “This is a reminder to my fellow warriors that it’s OK to have days where you don’t want to fight anymore. You don’t need to justify your mental health to anyone. Prioritize yourself when needed, take time to rest. Surround yourself with good people and high vibrations. But always remember you are always worth fighting for. And tomorrow could be such a beautiful day.”