On Facebook, the TV presenter admitted her trademark curls were fake and she was going through the perimenopause, which is the start of the menopause.
Sawalha said her hair "was my favourite thing about myself."
She revealed a doctor told her she had the balding gene on the ITV daytime show in September.
In the video, she breaks down telling people she used to say her hair was her "crowning glory" and did not realise the gene could occur in women.
She added: "My hair is not like that anymore, my hair really started to change after I had my kids.
"It sounds awful saying it as people lose all of their hair to alopecia or cancer treatment but it doesn't make it any easier, the fact that I'm losing my hair."
In sharing what Ms Sawalha describes as a "confession", she says she hopes "by speaking out it helps make you not feel alone in this and please share if you think it might help someone you know".
The menopause is the transition of when a woman stops having periods and is no longer able to get pregnant naturally.
Loose Women panellist Nadia Sawalha has posted an emotional video online talking about losing her hair at the age of 52.