Twenty-six going on 40? Lindsay Lohan's lifestyle leading to premature aging, experts say

“Lindsay Lohan Looking Old” is one of the top Google searches associated with the actress’s name, and for good reason.

Earlier this year, Lohan appeared with bleached blonde locks and a serious tan at an amFAR gala. Headlines included “Lindsay Lohan’s Red Carpet Look Disturbs Us,” “Lindsay Lohan Ages Self” and “25 Going on 40.”

A few months later, 66-year-old rocker Debbie Harry was mistaken for the “Mean Girls” star while walking the streets of Manhattan. According to the New York Post, a cluster of paparazzi thought that was Lohan donning very large dark glasses and a thick black coat, when it was in fact the Blondie front woman.

PHOTOS: Lindsay Lohan through the years.

Another story noted that Lohan even looked older than Paris Hilton, six years her senior, and known for closing as many clubs as Lohan.

According to multiple experts, Lohan's appearance is no great surprise. The half decade of personal problems that have plagued the actress appear to have taken the physical toll on her the 26-year-old’s once vibrant exterior, rendering her a woman who often looks far beyond her years.

According to Dr. Damon Raskin, addiction expert at Cliffside Malibu treatment facility, substance abuse ages the body, increases fine lines and causes premature aging.

“Key signs that indicate aging and not taking care of herself are changes in the skin tone and texture,” Raskin told FOX411’s Pop Tarts column.

Heather Lounsbury of Live Natural Live Well concurred that the years Lohan has spent burning the candle at both ends would leave anyone looking worse for wear.

“Overuse of alcohol, drugs, cigarettes, even coffee can cause premature aging for several reasons,” Lounsbury explained. “Dehydration, stress on the liver, vitamin C deficiency as all these substances deplete nutrients, as well as less collagen production and stress on the adrenal glands. That is why most addicts usually look older than they are.”

Dr. Nicholas Kardaras, an addictions specialist and Clinical Director of the Dunes, a holistic mind-body rehab center in Easthampton, N.Y. says substance abuse-related aging can be seen on the skin.

“This includes a blotchy, bloated appearance often accompanied by broken blood vessels (when this affects the nose area, it is commonly known as "drinker's nose"), but can affect other areas of the face and body as well,” he explained.

Contrast Lohan circa 2012 with the fresh-faced Hollywood “it” girl who in 2006 -- the year before her first arrest and subsequent years-long downward spiral -- turned heads when she stepped out at the Hollywood Film Festival with a glowing complexity and lustrous long locks.

“If I didn’t know anything about her, I would think she was in her mid-30’s,” Lounsbury noted. “Maybe older.”

And that may be a kind assessment.

“If I had to make an educated guess, I would say that she has the appearance of someone in their well-traveled 40s. Having said all that, it's obvious that this young woman is going through a difficult period,” Kardaras said. “I know all too well that it's no easy task getting clean and sober at any age, in any career, much less at such a young age and in the spotlight as much as she is. Those are certainly factors that are complicating her recovery process.”

The good news for the still-working actress, some of those physical signs of aging can be reversed or at least halted.

“She needs to stop using drugs, drinking and smoking,” Raskin added. “She needs to drink more water, and exercise.”