Our closest relatives, chimpanzees and gorillas, breast-feed their offspring for several years. Some baby orangutans nurse until they are 7 years old.
But modern humans wean much earlier. In preindustrial societies, babies stop nursing after about two years. Which raises the question: How did we get that way? When did we make the evolutionary shift from apelike parenting to the short breast-feeding period of humans?
As the country awaits two important Supreme Court decisions involving state laws on same-sex marriage, a small but consistent body of research suggests that laws that ban gay marriage — or approve it — can affect the mental health of gay, lesbian and bisexual Americans.
The American Psychiatric Association is about to release an updated version of its Diagnostic and Statistical Manual of Mental Disorders. The DSM helps mental health professionals decide who has problems such as depression, anxiety and schizophrenia.
Psychiatry's new manual, DSM-5, has been nearly 20 years in the making. During that time, scientists have learned a lot about the brain. Yet despite some tweaks to categories such as autism and mood disorders, DSM-5 is remarkably similar to the version issued in 1994.
Americans are repeatedly told to cut back on salt to reduce the risk of heart disease. But there are new questions being raised about the possible risks of reducing sodium too much.
So, how low should we go? Currently, the government recommends that Americans should aim for 2,300 milligrams per day. And people older than 50, as well as those with high blood pressure, diabetes or kidney disease are advised to reduce sodium even further, down to 1,500 mg per day.
Angelina Jolie just became part of a medical trend: More women are deciding to have their breasts removed to reduce the risk of cancer.
Over the past decade, doctors have noticed a big increase in the number of women choosing prophylactic, or preventive, mastectomies.
Some, like Jolie, have a genetic mutation that makes it much more likely that they will have breast cancer. Her mother died of the disease at age 56. Jolie is 37. She wrote about her decision in The New York Times.
When she was just 6, Emily Gorospe became very tired and sick. The spunky girl, now 8, developed a fever that wouldn't go away, and red blotches appeared across her body.
"She's got so much energy usually," says Emily's mother, Valerie Gorospe. "Just walking from one part of the house ... she was drained." The little girl was also very pale. "She just didn't look like herself," Valerie recalls.
Any gardener will tell you that compost is "black gold," essential to cultivating vigorous, flavorful crops. But it always feels like there's never enough, and its weight and bulk make it tough stuff to cart around.
I belong to a community garden in Washington, D.C., that can't get its hands on enough compost. So you can imagine my delight when I learned that the U.S. Composting Council was connecting community gardeners with free material from local facilities through its Million Tomato Compost Campaign.