5 studies you may have missed

Here's a roundup of five medical studies published this week that might give you new insights into your health. Remember, correlation is not causation – so if a study finds a connection between two things, it doesn't mean that one causes the other.

Don't diss canned vegetables

American Journal of Lifestyle Medicine

Researchers at Michigan State University analyzed more than 40 scientific journal studies to see if canned fruits and vegetables provide the same nutritional benefits as fresh and frozen produce. Cans are often cheaper than fresh or frozen products, and therefore easier for low-income families to buy.

The scientists concluded that not only are canned products on par with fresh and frozen produce nutritionally, in some cases they're better. Canned tomatoes, for instance, have more lycopene and more B vitamins.

"By increasing accessibility to key nutrients many Americans need, canned foods are a year-round solution to help families prepare healthier, balanced meals," Steven Miller, lead researcher and assistant professor at MSU's Center for Economic Analysis, said in a press release.

Want to prevent HIV and pregnancy? Put a ring on it

Journal: PLOS ONE

A team of researchers, led by Northwestern University biomedical engineer Patrick Kiser, has developed an intravaginal ring designed to prevent HIV and unwanted pregnancy.

The ring is the first device to deliver an antiretroviral drug (tenofovir) and a hormonal contraceptive (levonorgestrel), both of which are already used on the market. The device has been engineered to deliver specific amounts of the antiretroviral drug and contraceptive every day.

The researchers hope that administering this medication in an intravaginal ring will increase effectiveness and ease of use. The ring will be entered in clinical trials later this year.

“I think it’s a moment in women’s health to be excited about,” says Kiser. “There are a large number of people working very hard to get these kinds of products into the market and into the hands of women.”

Take the TV out of your kid's bedroom

Journal: JAMA Pediatrics

Having a television in his or her bedroom could be increasing your child's weight. A survey of more than 6,000 kids aged 10 to 14 showed those with a TV in their bedroom gained more weight than those who didn't over a four-year time period. This held true even after the researchers adjusted the results for total TV viewing time.

The individual weight difference was small, but close to 60% of children in that age group reported having a TV in their bedrooms. "With the high prevalence of bedroom televisions, the effect attributable to this risk factor among U.S. children and adolescents is excess weight of 8.7 million kg/(year)," the researchers concluded.

We eat better when we're happier

Journal of Consumer Psychology

Anyone who's ever downed a tub of ice cream after a rough day knows bad moods breed bad food choices. But are we more likely to stick to salad when we're in a good mood?

In a series of studies, researchers analyzed the food choices of people in good, bad and neutral moods. They found those in a good mood tended to make better choices, while those in a bad mood chowed down on M&Ms. They hypothesized that this is because people in a good mood are able to see past the immediate benefits of bad mood (mmmm, chocolate) to the long-term benefits of nutritious foods.

“When we think about the future, it's almost as if we are physically taking a step back, enabling us to see our more fundamental values – like health and nutrition," co-author Meryl P. Gardner, an associate professor of marketing at the University of Delaware’s Lerner College, said in a press release. "We can use that to make wiser choices rather than letting our moods dictate our behavior.”

You may want to test both arms

The American Journal of Medicine

When you go to the doctor for your annual checkup, he or she probably takes your blood pressure reading on one arm. But new research suggests checking both arms is a better predictor of whether you'll have a cardiovascular event -- i.e. a heart attack or stroke -- in the future.

Scientists examined data from 3,390 people over 40. They found participants who had a systolic blood pressure reading (the top number) in one arm that was different by 10 or more digits than the reading in the other arm had a 38% greater risk of a cardiovascular event.

In other words, a person with a 180/90 BP in one arm, and a 200/90 BP in the other would be more at risk than someone who had a 190/90 BP in one arm and a 195/90 BP in the other.

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