Malaysian icon Datuk Siti Nurhaliza has a secret to looking young and beautiful, and she wants to share it with everyone.

"Beauty is a gift from God, but it needs to be constantly nurtured. It is important to take care of yourself from inside out or you'll age before your time," said the singer at the launch of Sity Avita in Menara UOA Bangsar.

The star also believes that "you are what you put in your body" and reveals that beauty brand Avita's star product, Celergen, keeps her looking young and vibrant.

Celergen is an "anti-ageing" supplement from Switzerland.

"It helps repair and maintain cells irrespective of your age," said Siti, looking resplendent, with a smile.

Siti, who started using Celergen about a year ago, was so impressed with the results that she felt "brave enough" to invest in Avita, an international brand that has made its presence felt across Asia.

As a result, Sity Avita Sdn Bhd was born.

"My friends and family who have tried the product all wanted more of it. That's why I feel really confident about my new business venture," she said.

Though when asked about how much she invested, the singer was coy: "Oh, not much," and declined to comment further.

However, Siti is loud and proud about her other beauty brand, Simply Siti.

"It's only eight months old but it has received good response from fans so far. I hope that Sity Avita will be equally successful. I hope to break into the Indonesian market too."

While a product with her name on it is likely to boost sales, the singer insisted: "I truly believe it is a good product and we should let it speak for itself."

"But of course, staying young and beautiful doesn't mean I can rely solely on the product. I have to exercise too."

On a more contemplative note, Siti said that while her singing career has given her a good life, it has a limited time span. "It has gotten me where I am and I'm very grateful but it can't last forever. I hope to venture into different businesses in the future."