Harvard Health Content API

Recent studies suggest that cooling off to burn more fat is an idea worth exploring, Dutch researchers say. The new report reviews recent human and animal studies. They focus on the activity of “brown fat,” which is found in only small amounts in most adults. Brown fat burns calories to help us stay warm in cold temperatures. Shivering increases heat production in people. More recent studies also suggest that the body burns more calories for heat even when exposed to milder cold temperatures. This is called non-shivering thermogenesis. Earlier research by the Dutch team showed that people tend to feel more comfortable over time when exposed to chilly temperatures (about 59 degrees Fahrenheit). The Dutch researchers are planning longer-term experiments that will also track the weight of people who live in cooler environments over time.

Women who consume high levels of omega-3 fatty acids may be less likely to lose brain cells as they get older, a new study suggests. Omega-3 fatty acids are found in fish oil and some supplements. Researchers measured omega-3 levels in the red blood cells of more than 1,000 older women. Their average age was about 70. Eight years later, they were given MRI scans of the brain. Women with high levels of omega-3 fatty acids had larger brains than those with low levels. The difference was equal to about 1 or 2 years of normal brain shrinkage for adults in this age group. Women with higher omega-3 levels also tended to have a larger hippocampus. This part of the brain has a major role in memory. It begins to shrink early for someone with Alzheimer’s disease. The new study only shows a link between higher omega-3 fat levels in the bloodstream and larger brain size.

Your chance of dying from a heart attack is greater if you seek care at night or on a weekend, a research review finds. The study put together results from 48 earlier studies. They included nearly 1.9 million patients. The studies were from the United States, Canada and Europe. People who arrived at hospitals during off-hours had a 5% higher risk of death in the hospital than those who came in on weekdays. The risk of death within 30 days was also 5% higher. Researchers estimated that this led to 6,000 extra deaths each year in the United States alone. One possible reason for the difference is treatment delays during off-hours. The study estimated that for one common type of heart attack, a 15-minute delay could increase death by 10% to 15%. The journal BMJ published the study online.

Girl soccer players in middle school often keep playing despite concussions, new research has found. And these injuries are common. About 13% of players had concussions in a typical season, the study found. That was higher than reported in previous studies of high school and college players. Researchers recruited 351 girls from elite soccer teams. They were 11 through 14 years old. The study covered the years 2008 through 2012. About 82% of the girls played for 1 year and 18% for 2 years of the study. Researchers sent weekly e-mails to parents during soccer season. They asked about any blows to the head and any symptoms that followed. Players who had these incidents got phone calls from research staff. They were asked how the injury occurred, whether they continued to play, and what type of care they got. In all, 59 concussions occurred.