In the new book “XL Love” (Rodale), health-policy journalist Sarah Varney describes the negative effects of childhood obesity, which begin surprisingly early for many — such as how overweight girls begin puberty younger than their healthy-weight counterparts.

“Some 15% of American girls now begin puberty by first or second grade,” Varney writes. “Over the last quarter-century, the age at which American girls begin menstruating has decreased by 2.5 months.”

Carlton Gorton, a doctor in Belzoni, Miss., an area with higher-than-average rates of obesity, told Varney that “he has discovered girls as young as 5 and 6 years old who are developing pubic hair. These alarming signs of puberty are usually related to his patients’ ample body fat.”

Some of these young patients, whom the doctor describes as “off the growth chart,” even come to him for monthly hormone shots that “hold them off from going through puberty.”

Early puberty, meanwhile, leads to a host of dangerous issues.

“Among girls who go though early puberty,” Varney writes, “there is an increased incidence of depression; alcohol, tobacco and substance abuse; riskier sexual adventures; teen pregnancy; and even suicide attempts.”

Obesity ruins your sex life

While overweight boys might not have the depth of challenges overweight girls do, once into adulthood — where 80% of those boys will remain overweight — the extra weight creates similar feelings of inadequacy, along with unique and troubling problems of their own.

“For every 50 pounds overweight you are, you lose an inch of penis,” Dr. Edward Karpman, a California urologist, says in the book.

“A man’s penis is actually fixed to his abdominal wall, holding it in place,” writes Varney, based on Karpman’s explanation. “The more a man’s fattening belly grows outward, ‘the more it eats their penis,’ leaving them with, according to the doctor, ‘this little nubbin of a penis.’”

Extremely obese men face an extreme version of that, called “buried penis syndrome.”

As Varney explains, “abdominal fat and skin drape out and over a man’s pubic area, causing a host of problems.”

Keep reading…