Harvard Health Content API

Kids who play multiple sports, and kids who walk or bike to school, are less likely to be obese, a new study finds. The study was based on a series of surveys of 1,700 teens and their parents. They were asked about sports and other physical activities, including how often they biked or walked to school. Researchers also asked about the teens’ height and weight. Those who played at least 3 sports were 27% less likely to be overweight than those who played no sports. They were 39% less likely to be obese. Teens who walked or biked to school 3.5 days a week were 33% less likely to be obese than those who were always driven to school. But the two groups were equally likely to be overweight. Physical education classes had no effect on obesity. Neither did active pastimes other than sports. Researchers said obesity would decrease by 26% if all teens played at least 2 sports.

Changes in the brain and the fluid around it may occur as much as 25 years before symptoms of early-onset Alzheimer’s disease, a new study finds. The study focused on 128 people. All had a family history of early Alzheimer’s caused by a gene inherited from one parent. Symptoms start in the 30s, 40s or 50s. About half of those in the study carried the gene. Researchers gave everyone several tests. They determined when symptoms would be expected to start based on the parent’s age at diagnosis. About 25 years before symptoms were expected, those with the gene showed a drop in beta-amyloid in the fluid around the brain. This is a key component of Alzheimer’s plaques inside the brain. About 15 years before symptoms were expected, people with the gene had smaller brains, and plaques had appeared. Fluid around the brain also had more tau protein. This is another sign of Alzheimer’s.

Final results from 2 studies suggest that taking HIV medicines can also help to prevent the disease in high-risk people. All of the studies were done in Africa. One included 1,219 heterosexual men and women. They were randomly assigned to receive either two antiviral drugs or placebo (fake) pills. The drugs were tenofovir and emtricitabine. People who got the real drugs were 60% less likely to become infected with HIV. The second study involved more than 4,700 heterosexual couples. One partner in each couple was infected with HIV. The non-infected partners took a pill daily. The pills contained the same 2 drugs used in the first study, tenofovir alone, or no medicine (placebo). Infection rates were 67% to 75% lower for those who got the real drugs. A third study included 2,120 women. It did not find a benefit from antiviral drugs. But many women admitted skipping pills often.

About 1 in 5 older U.S. adults has a mental illness or substance abuse problem, a new report says. The numbers will only climb as baby boomers get older. And that may create problems with access to care, the report predicts. The United States does not have enough health workers trained for the special needs of older adults, the report says. The Institute of Medicine, an independent group of experts, released the report. It says that 5.6 million to 8 million people 65 and older have mental health or substance abuse problems. Baby boomers have higher rates of illegal drug use than earlier groups. So they may have greater needs for substance abuse treatment. Mental health problems in older adults may be harder to diagnose and more complicated to treat, the report says. Long-term medical conditions can mask depression symptoms. Drugs for other illnesses also may affect mood.

Women infected with a common parasite may be more likely to harm themselves, a study suggests. The study was based on records for 45,788 new mothers in Denmark. All of them had been part of a study that tested newborn babies for antibodies against the Toxoplasma gondii parasite. The antibodies come from the mother, cross the placenta and get into the newborn. This parasite causes the infection toxoplasmosis. People can become infected by handling cat litter. Other causes include eating undercooked meat or unwashed vegetables. The infection may remain in a person’s brain or body for years and cause no symptoms. However, it can be dangerous for a fetus or someone with a weak immune system. Newborns can’t make these antibodies, so testing the newborns identified which mothers had toxoplasmosis some time in their lives.

What leads to a better quality of life right before death? A new study of advanced cancer patients finds that it helps to die at home, avoid aggressive treatment, and have a close relationship with your doctor. Spiritual factors also made a difference. Prayer, meditation and a visit from a pastor helped people feel more peace at the end. So did relief from worry and anxiety. The study included about 400 people with cancer. All had been told they had less than 6 months to live. They were surveyed an average of 4 months before they died. They were asked about their quality of life. Caregivers were surveyed after the person’s death. They were asked about the person’s quality of life at the end. Dying in a hospital, especially intensive care, was linked with lower quality of life. So was having a feeding tube or aggressive treatment, such as chemotherapy.