Instagram does not allow children under 13 to have accounts, but parents are allowed to run them — and many do so for daughters who aspire to be social media influencers.

What often starts as a parent’s effort to jump-start a child’s modeling career, or win favors from clothing brands, can quickly descend into a dark underworld dominated by adult men, many of whom openly admit on other platforms to being sexually attracted to children, an investigation by The New York Times found.

Thousands of so-called mom-run accounts examined by The Times offer disturbing insights into how social media is reshaping childhood, especially for girls, with direct parental encouragement and involvement.

Nearly one in three preteens list influencing as a career goal, and 11 percent of those born in Generation Z, between 1997 and 2012, describe themselves as influencers. But health and technology experts have recently cautioned that social media presents a “profound risk of harm” for girls. Constant comparisons to their peers and face-altering filters are driving negative feelings of self-worth and promoting objectification of their bodies, researchers found.

The pursuit of online fame, particularly through Instagram, has supercharged the often toxic phenomenon, The Times found, encouraging parents to commodify their daughter’s images. These are some key findings.