Jessica Simpson's recent transformation into a much slimmer figure has friends worried for her well-being, insiders reveal. The singer, who once had a more substantial physique, was seen in New York City displaying a noticeably thinner appearance. The fashion entrepreneur lost 100 pounds from her 5-foot-3 frame three years ago, but sources claim the star's weight continues to decline.

"Jessica appears to weigh less than her ten-year-old daughter, Maxwell," shares an insider. The 42-year-old celebrity, who is married to retired football player Eric Johnson, maintains that she feels "healthy" and even boasts about fitting into clothes she saved for her daughters, Maxwell and Birdie, 4.

However, some close to the singer express their concern over her increasingly slim figure.

"It's alarming that a 42-year-old woman fits into clothes she wore as a child," a worried source points out.

Jessica Simpson, known for her fluctuating weight throughout her career, has confessed to having been "every size." Currently estimated at 100 pounds, she reached a peak of 240 pounds around the time of her daughter Birdie's birth.

A physician who has not treated Jessica cautions, "This kind of radical yo-yoing erodes muscle and bone health, increasing the risk of osteoporosis!"