Science looked at everything from car seat safety to how dogs help kids.
Parenting is as personal as it gets, and so much of it comes straight from the gut. You know your child best. And at the end of the day you have to make decisions about what's right for them using some unknowable combination of instinct, experience and trusted personal advice.
But that doesn't mean that the world of science doesn't have a lot to offer caregivers, especially when it comes to understanding and promoting their children's health. With that in mind, here, in no particular order, are 10 of the most interesting health studies from the past year that every parent should read. You're the expert, but science can help.
Reading changes kids' brains.
Parents and pediatricians have long known that reading has huge benefits for young children, but in 2015, science offered the first hard proof that it actually changes kids' brains, as well as insights into how, exactly, it all goes down.
Using MRIs, investigators looked into the brains of 3- to 5-year-olds and found concrete visual evidence that reading to preschoolers activates the parts of their brains that help with mental imagery and understanding narrative -- both of which are essential for the development of language and literacy. Read on!
75 percent of parents face car seats the wrong way.
More and more parents are becoming aware of how widespread car seat errors are, and that's undeniably a good thing. But a January study found that a majority of parents are still making at least one big-time mistake by failing to follow advice about how long their children should sit in rear-facing car seats.
The American Academy of Pediatrics recommends that parents keep toddlers in rear-facing car seats until they either turn 2 or reach the maximum height and weight for their rear-facing seat. But researchers found that most parents turn their child's car seat around to a front-facing position earlier than is recommended, and a quarter of parents turn them around before their children's first birthday.
Children with pet dogs are less likely to have anxiety issues.
Parents may not have needed a study to tell them that dogs can do good things for children's mental health, but they got one in 2015 nonetheless. An investigation published in the fall found that children who live in homes with dogs are less likely to meet clinical thresholds for anxiety and related disorders than children in dog-free homes.
"Pet dogs could reduce childhood anxiety, particularly social and separation anxiety, by various mechanisms," the study authors wrote.
Kids should probably eat less pizza.
Yes, it's kind of a downer. And yes, it might seem pretty darn obvious. But a study published in 2015 got a lot of attention for showing the extent to which pizza contributes to American kids' intake of salt, calories and saturated fat.
On any given day, about 20 percent of children and teens eat pizza, the researchers found -- and on those days, children generally tend to eat more salt, calories and saturated fat overall. Parents should really try and limit their kids' overall pizza intake, the researchers urged, or at least make it healthier when it is on the menu, by adding veggie toppings, for example.
ADHD rates are up -- especially in girls.
Attention deficit hyperactivity disorder, or ADHD, has long been thought of as largely a boy's issue. But a new analysis of national data released in December found that not only is the overall prevalence of ADHD diagnoses up in the United States (by 43 percent among school-age children, according to their parents), there has also been a surprising jump in diagnoses among girls. Between the study period of 2003 and 2011, diagnoses increased by 55 percent among girls.
Why? That's the big next question, researchers say -- and they don't have an answer yet. It could be that doctors have simply begun to recognize that girls have symptoms other than "classic" signs, like impulsivity and an inability to focus. It also may well be that over-diagnosis is at play. For now, the study makes it clear that ADHD continues to be common -- and that parents, teachers and doctors shouldn't overlook it as a potential issue among certain subgroups of children who may have been missed in the past.
Autism diagnoses may also be up.
Pinning down autism spectrum disorder (ASD) rates can be tricky, and national projections differ pretty significantly in some cases. In November, the CDC released a new and startling estimate that suggests 1 in 45 children in the United States now has ASD. That estimate is higher than an often-cited (but also current) CDC figure of 1 in 68 children -- and the difference likely has much to do with how both sets of data were collected. The 1 in 45 estimate comes from parent interviews, whereas the 1 in 68 figure comes directly from medical records.
For now, the 1 in 68 figure will still be treated as the best estimate, Michael Rosanoff, director of public health research for the advocacy group Autism Speaks told Yahoo News -- but the 1 in 45 figure lends support to the idea 1 in 68 is an underestimate.
Picky eating may not just be a benign, passing phase.
Picky eating is practically a rite of passage for grumpy toddlers and their exhausted parents, but in 2015, researchers argued that it shouldn't necessarily be written off as "just a phase." Investigators found that preschoolers who were so-called selective eaters -- meaning they were often or almost always picky about what they ate -- were also potentially at greater risk for anxiety and depression.
The study did not establish cause and effect, and the researchers said it's likely not a simple relationship. For now, it's something parents and doctors should pay attention to, particularly when picky eating becomes truly disruptive.
Delaying cord clamping could have benefits that last for years.
While it's certainly not always possible for doctors and midwives to delay clamping a baby's umbilical cord, a 2015 study added to the growing body of evidence suggesting that it can be a very good thing when care providers can hold off. Researchers found that children whose cords were cut more than three minutes after they were born had slightly higher social and fine motor skills years later. Delaying clamping the cord allows more blood to reach the baby from the placenta, and can boost babies' iron storage, which helps brain development.
A startling number of children are assaulted by their siblings.
More than one-third of children in the United States experienced some form of physical violence between 2013 and 2014, according to a study released this past year -- and the majority of those incidents involved siblings. The research drew attention to just how damaging sibling violence can be, even though parents may be inclined to simply write it off as a normal part of growing up.
"Our research suggests sibling victimization is a major source of trauma and distress in the lives of children," one of the study's authors told The Huffington Post.
A measles outbreak showed how important vaccination is.
Between January and November of 2015, the United States experienced several outbreaks of measles, resulting in 189 cases. The increase in measles cases in recent years, after measles had been officially eliminated in the United States in 2000, has much to do with under-vaccination in certain pockets of the country, as well as under-vaccination abroad. The CDC believes that the 2015 outbreak linked to a California amusement park likely started with a traveler from overseas -- and the majority of people who got measles were unvaccinated. That's why in 2015, many parents and care providers spoke out about the importance of childhood vaccination