THURSDAY, June 23 (HealthDay News) -- Who do teens look to as role models for healthy sexual behavior? According to a new Canadian study, they look first to the example set by their parents, not to friends or the media.

(HealthDay News) -- Gallstones are deposits that develop in the gallbladder from sources such as excess bilirubin or cholesterol.

(HealthDay News) -- Babies that cry frequently for hours at a time and are fussy for reasons you or your doctor can't explain may have colic.

THURSDAY, June 23 (HealthDay News) -- New research suggests that the adverse effects of pre-term birth can extend well into adulthood.

THURSDAY, June 23 (HealthDay News) -- Cocaine contaminated with levamisole, a cheap and widely available drug used to deworm livestock, could result in a U.S. public health epidemic, experts warn.

THURSDAY, June 23 (HealthDay News) -- Among heart attack patients, black Americans generally wait longer than whites to undergo revascularization procedures to restore blood flow to their hearts, according to a new study.

THURSDAY, June 23 (HealthDay News) -- Being married improves the likelihood of survival for colon cancer patients, a new study finds.

THURSDAY, June 23 (HealthDay News) -- Minimally invasive colon surgery reduces the risk of blood clots in the deep veins compared with traditional surgery, University of California, Irvine, researchers report.

THURSDAY, June 23 (HealthDay News) -- Rehab admissions related to alcohol, opiates (including prescription painkillers) and marijuana increased in the United States between 1999 and 2009, according to a new national report.

THURSDAY, June 23 (HealthDay News) -- An implantable device hidden in the nape of the neck may mean more headache-free days for people with severe migraines that don't respond to other treatments, a new study suggests.

WEDNESDAY, June 22 (HealthDay News) -- The strain of E. coli bacteria that this month killed dozens of people in Europe and sickened thousands more may be more deadly because of the way it has evolved, a new study suggests.

WEDNESDAY, June 22 (HealthDay News) -- The recently approved drug Incivek, combined with two standard drugs, is highly effective at treating hepatitis C, a notoriously difficult-to-manage liver disease, two new studies show.

THURSDAY, June 23 (HealthDay News) -- With record-breaking wildfires scorching the American Southwest, experts are worried not just about the environmental and property damage, but also about health risks both to nearby residents and to those living farther away.

THURSDAY, June 23 (HealthDay News) -- The creaminess of fat-rich foods such as ice cream and salad dressing appeal to many, but new evidence indicates that some people can actually "taste" the fat lurking in rich foods and that those who can't may end up eating more of those foods.

Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

THURSDAY, June 23 (HealthDay News) -- Strategies to encourage physical activity, healthy eating and good sleep habits are needed to reduce high rates of obesity among infants, toddlers and preschoolers in the United States, says an Institute of Medicine report released Thursday.

THURSDAY, June 23 (HealthDay News) -- A trial HIV testing program screened nearly 2.8 million Americans from 2007 to 2010 and identified 18,432 people infected with the AIDS-causing virus, federal health officials said Thursday.

THURSDAY, June 23 (HealthDay News) -- After suffering a stroke, patients who talk with a therapist about their hopes and fears about the future are less depressed and live longer than patients who don't, British researchers say.