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, mind and body. Remember, correlation is not causation – so if a study finds a connection between two things, it doesn't mean that one causes the other.

Pregnant moms: Be careful when you are driving
Journal: Canadian Medical Association

A study out of Canada suggests women in their second trimester of pregnancy are more likely to have a traffic accident than other women.

Researchers looked at every newborn in Ontario, Canada, over a five-year span. They found a 42% increase of life-threatening motor accidents in the second trimester of their pregnancy.

Why? Researchers believe it is because pregnant women tend to suffer more from things such as fatigue, stress and nausea than women who aren’t pregnant.

Statistics show pregnant women are more likely to have a motor vehicle accident than develop a medical condition such as preeclampsia, says Dr. Donald Redelmeier, lead study author and researcher in the University of Toronto’s Department of Medicine.

So should pregnant women stop driving as their due date draws closer?

“What we're not seeing is a reason to delegate driving to husbands,” says Redelmeier. He points out that men in this same age group still have many more traffic accidents than women.

Driving under the influence of marijuana is also a bad idea
Journal: JAMA Pediatrics

Speaking of driving, we hear a lot about the dangers of getting behind the wheel while drunk, but we may need to issue similar warnings about marijuana.

Researchers did a telephone survey of 315 first-year college students and found that 44% of the men said they had driven while stoned in the previous month. By comparison, 12% said they had driven after consuming alcohol.

For women in college, driving while under the influence of marijuana was less common - only 9% reported doing so - and only about 3% said they drove after drinking. But 35% of female respondents said they were passengers in a car driven by someone who had been using marijuana. Riding with a stoned driver was even more prevalent among men, with 51% saying they'd had that experience.

"We definitely need to think about how to help students understand that marijuana is risky to use before you drive," lead study author Jennifer Whitehill, an assistant professor at the University of Massachusetts, Amherst, told HealthDay. "These are young, inexperienced drivers, and marijuana does increase crash risk."

Read more at Philly.com

Antidepressants may slow Alzheimer's progress
Journal: Science Translational Medicine

One of the biological signatures associated with Alzheimer's disease is the buildup of beta-amyloid plaques in the brain. Research suggests that antidepressant medications may help stop that buildup.

The drug citalopram showed this effect in a mouse with Alzheimer's. The growth of pre-existing plaques was stopped, and the introduction of new plaques was reduced by 78% as a result of this drug.

Researchers also saw an effect in humans, although they did not look at anyone who has Alzheimer's disease. There were 23 participants from 18 and 50 who did not have cognitive impairment or depression at the time of the study. In these people, amyloid-beta production dropped by 37% in the 24 hours after taking one dose of citalopram.

This does not mean everyone should take antidepressants to prevent Alzheimer's disease. More research is needed on this subject to see how antidepressants may affect the condition.

Read more from Science Daily

Stem cells help mice with MS walk again
Journal: Stem Cell Reports

Mice that were once paralyzed can walk again thanks to a stem cell therapy tested in a study. This confirms previous findings that suggest stem cells could be beneficial in treating multiple sclerosis, though so far the benefits have only been shown in rodent studies.

Researchers transplanted neural precursor cells that were derived from human embryonic stem cells. These cells communicated with mouse cells, telling them to heal the MS-induced damage.

Close to three quarters of the mice saw a reduction of symptoms as a result of this treatment, 10 to 14 days after receiving it.

But what chemical signals generated by the stem cells are responsible for the mice's recovery? Researchers need to figure that out before developing a treatment to test in humans.

"It would be easier to find a family of proteins exerting these protective effects and make them into an injectable drug or pill," Tom Lane, a pathologist at the University of Utah, told The Salt Lake Tribune.

Read more from The Salt Lake Tribune

Get forgiven, then forgive yourself
Journal: The Journal of Positive Psychology

Feeling guilty? A study suggests that you may need to make things right with others before you can get over it.

"One of the barriers people face in forgiving themselves appears to be that people feel morally obligated to hang on to those feelings," researcher Thomas Carpenter, a doctoral student in psychology in Baylor's College of Arts and Sciences, said in a statement to Science Daily. "They feel they deserve to feel bad. Our study found that making amends gives us permission to let go."

The research group asked questions about transgressions, guilt and forgiveness in two separate studies.

First, participants were asked to recall offenses they had personally committed. Making amends appeared to be related to people's ability to forgive themselves.

In the second study, they asked everyone about the same offense: Imagine you caused a friend to get fired, but you didn't take the blame for it. This time, forgiving oneself wasn't as related to being forgiven by others.

A larger finding of the study was that more serious wrongdoings were harder for people to get over in terms of forgiving themselves - the same goes for the more guilt they were feeling.

More research is needed on this subject, but remember that "I'm sorry" can go a long way.

Read more from TIME.com