The growth spurt in girls typically occurs two years earlier than in boys, according to the American Academy of Family Physicians. Body parts may grow at different rates, and teens often appear clumsy and feel awkward during this period.

Both boys and girls need a calcium-rich diet during their teen years to ensure they store up enough calcium in their bones, says the National Institute of Child Health and Human Development.

A physician should monitor adolescent growth and development.

The Tdap booster is recommended for teens at ages 11 to 12. Teens 13 to 18 who missed getting the Tdap booster at ages 11 to 12 should also receive it. Those who received a tetanus-diphtheria (Td) booster at ages 11 to 12 should receive Tdap for additional protection against pertussis, as long as at least five years have elapsed since receiving the last tetanus containing vaccine—although a shorter interval may be used, the Centers for Disease Control and Prevention says. Teens should also get a "catch-up" immunization for measles, mumps, and rubella, and chickenpox, if they missed a recommended dose in childhood.

Nearsightedness, or myopia, usually starts in childhood and then gets progressively worse during the teen years, according to experts at the University of Missouri-Kansas City School of Medicine. The progression usually eases up by the time a person reaches his or her mid-20s.

According to the National Institute on Drug Abuse, about 1.5 percent of eighth graders and 1.8 percent of 10th graders have used anabolic steroids. Among high school seniors, the figure is 2.2 percent.

They may also be symptoms of illness. Check for drug paraphernalia, and have your pediatrician examine the teenager to rule out other possible causes.