Lopez, who graces the cover of the magazine's February issue, on newsstands Friday, says "being an example to others is a big part of my work."
The 38-year-old singer-actress also says she would like to have children someday.
"I come from a strong family, so of course I want to have one," Lopez tells the magazine. "But I do have my own family: my immediate family, my husband and his children. I get to share in all of that. I am very lucky to have that."
Marc Anthony, who didn't make the list, and Lopez were married in 2004. The 37-year-old singer has two sons, 5-year-old Cristian and 3-year-old Ryan, with ex-wife Dayanara Torres, and a 12-year-old daughter, Arianna, from a previous relationship.
"I have tried to calm down the past couple of years since I got married," Lopez says. "I have actually grown as an artist and as a person. I realized that everything I was doing leaned toward my roots ..."
Lopez tops the list of entertainers, which also includes Antonio Banderas, Carlos Santana, Eva Longoria, George Lopez, Gloria Estefan, Ricky Martin, Salma Hayek and Shakira, among others.
The magazine also honors filmmaker Alejandro Gonzalez Inarritu (culture/the arts), Attorney General Alberto Gonzales (politics/public affairs), businessman Carlos Slim Helu (business), MTV President Christina Norman (media), Los Angeles Angels of Anaheim owner Arturo Arte Moreno (sports), sociologist Aida Giachello (science and technology/health) and teacher Bertha Flores (education).
Lopez' screen credits include "Selena," "Maid in Manhattan" and "Monster-in-Law." She has recorded her first Spanish language CD, "Como ama una mujer," which is slated for release this spring.
"When I see all of this, I say to myself: 'Wow! I didn't know I had so many things inside,'" she says. "I am happy to have taken the time to appreciate it."