Our grandmas and Jenny McCarthy are guilty of the same crime.

They've pushed some bit of parenting advice -- unfounded in science but still a deeply held belief; rooted in intuition and circulated by word-of-mouth.

This is not to malign Granny, nor her intentions. There's wisdom that comes with experience, and it is valuable in its own right.

McCarthy, however, took parenting myth-making to towering, destructive heights when she claimed years ago that a vaccine caused her son's autism. (Any link between autism and vaccines has been widely discredited.)

From the minor and inconsequential to the monumental, there are hundreds of myths about raising children, and we are all likely to buy into at least a few of them.

Professors Stephen Hupp and Jeremy Jewell set out to debunk common parenting lore with the best available science. They are co-authors of the newly published "Great Myths of Child Development," and teach psychology at Southern Illinois University Edwardsville.

"I grew up in Missouri. It's the Show-Me State," Hupp said. "I was raised to be skeptical about claims." He is the father of two children, and was surprised by some of the things he discovered while researching the book. He learned about scientific rarities, such as women who are able to get pregnant again early in their pregnancies. It's very rare, but a woman can carry two babies conceived on different dates.

The 50 myths they deconstruct in their book range from conception to adolescence. I was most interested in the ideas we buy into that feed our own collective guilt or sense of superiority.

For example, there's a widespread belief that attachment parenting creates a stronger bond between a parent and child. The authors evaluated this claim by looking at research that sought to answer three questions: Are there lasting impacts from a mother and child immediately bonding after birth? Are there benefits to breast-feeding beyond two years? Does nightly co-sleeping promote attachment?

In each of these cases, they found no evidence of a lasting benefit from these behaviors.

"It's not like we criticize every aspect (of attachment parenting)," Hupp said. "We just want parents to be cautious. Not everything tied to attachment parenting is a research-supported idea."

They also found that research supports the "cry-it-out" method for sleep-training babies as effective without long-term negative effects. Also under the umbrella of things parents feel guilty about but shouldn't: Children who have spent time in day care do just as well later as children who haven't. Day care does not hurt parent-child attachment, Hupp said.

I fall on the attachment side of the early childhood parenting divide, but I can accept that I may not have chosen that path because of long-term benefits to my child, but rather because of short-term benefits to myself. It felt like I was fighting evolutionary instincts to let a baby cry it out at night, even if I knew intellectually that it would not permanently scar a child to learn how to sleep alone.

This is how it goes with many of the myths we choose to believe. They are repeated often enough. They make intuitive sense. They appeal to our fears, anxieties or offer an explanation for an unknown.

Plus, science evolves. Data are imperfect. Even the experts change their minds over time.

But there is a lot to be learned by challenging conventional wisdom and looking at which scientifically tested ideas can make us better parents. Hupp and Jewell's book offers these evidence-backed tips: Brief time-outs are an effective tool in decreasing challenging behaviors in toddlers. But "scared straight" programs designed to prevent delinquency actually lead to a greater likelihood to commit future crimes.

On the other hand, parents who give children commands with praise are likely to see greater compliance. Rewards used to increase desirable behavior in children actually work. Hupp said parents can use a reward to start a new behavior, then gradually phase out the reward over time. This may be one of those places where science confirms age-old wisdom.

Turns out, bribes work.

Grandma could have told us that.

I joke about how grateful I'll be to hand the car keys to our children and relinquish my role as chauffeur.

But behind that false bravado lies an anxious fear so many parents feel when a child is finally old enough to drive. We are handing them the keys to a machine that could potentially be lethal. And having been teenagers once ourselves, we remember that dangerous sense of invincibility.

So, we make sure they learn the fundamentals of how to drive. They have to pass a written test, a road test and an eyesight exam. We never let them ride without seat belts. We talk to them about the dangers of drunken driving and texting while driving. We establish the rules.

This year, more Americans are likely to die of gunshot wounds than car accidents.

There were 33,804 motor vehicle deaths in 2013, according to the Centers for Disease Control and Prevention. There were 33,636 firearm deaths that year. Analysis by Bloomberg predicted that those numbers will soon flip, based on 10-year trends.

Similarly, a report last year by the Center for American Progress predicted gun deaths for teens and young adults are on track to surpass motor vehicle traffic deaths this year.

Gun violence disproportionately impacts teens and young adults. But lacking clear-cut conversations like those about car safety, how do parents begin to talk to teenagers and young adults about possible encounters with firearms? Which circumstances increase their risk of being victimized, and what can be done to lower those risks?

Despite news reports, our children are not very likely to encounter a shooter at a school, college, movie theater or shopping mall.

Rather, a confrontation with someone they know -- a personal relationship, a former boyfriend or spouse, a family member, an acquaintance -- is more likely to result in gun violence. And more than half of firearm-related fatalities are suicides.

Jeffrey Swanson, professor of psychiatry and behavioral sciences at Duke University School of Medicine, is co-editor of a special issue on gun violence to be published next month in Behavioral Sciences and the Law. He is a co-author on a new research study that finds "a distressingly large number of seriously angry people with guns -- often multiple guns -- living in our communities."

Their analysis of data from the National Comorbidity Survey looks at the responses when interview subjects were asked whether they had serious anger outbursts, such as losing their temper, smashing and breaking things, or getting in physical fights. Responses were combined with information from another section of the survey about possessing or carrying firearms.

"It comes to 10 percent of this (nationally representative) sample of adults who have impulsive, angry behavior and access to guns," he said. They are mostly young to middle-aged men, Swanson said.

Teens and young adults should know this and understand the implications of that risk.

"The presence of a weapon dramatically increases the probability of a death, and guns are so much more efficient at killing people," said Harold Pollack, professor of Social Service Administration and Public Health Sciences at the University of Chicago. "One of the most serious risks is of suicide of a family member because a firearm is available. It's a much more common problem than an intruder who seeks to kill you."

He spoke more bluntly about the responsibility of parents in such cases: "If I had a teenage son who was depressed, that would weigh very highly in my personal calculation of whether I'd want to have a firearm in my home."

If a child or adult is going through a rough patch, seek a safe place to store a firearm well outside his or her reach. In a few places, guns can be legally removed from those family members believed to be a risk to themselves or others. Pollack pointed out that some gun ranges have smart interventions to try to identify people at risk for suicide.

"These are done by people who are often very strong supporters of gun rights, but care a lot about the safety of people," he said.

Accidental or unintentional gun deaths are not limited to young children.

While brandishing a weapon is illegal in all states, showing it in an intimidating or impressionable way can also be a crime. Take it seriously and report it to police.

Even in states in which it's legal to openly carry or concealed-carry a gun, a person entering your living space can be asked not to carry a weapon onto private property -- or be asked to leave. If the person refuses, he or she can be arrested for trespassing.

Changes in public policy, attitudes and behaviors have been successful at lowering the rate of car fatalities for young people. Rather than becoming desensitized to this high level of gun violence, parents can use this heightened awareness to start a conversation. We need to be more proactive in talking to our children about a machine that may soon kill more of their peers than a car.

Whenever a child comes to my house for the first time, I make a point to ask the parent if the child has any food allergies.

If the child did have a life-threatening allergy, the parent would probably offer that information unprompted. But it's become such a part of the parenting culture to inquire -- a prerequisite for playdates or sleepovers.

Statistically speaking, however, a child is more likely to be accidentally shot and killed by a firearm than die of an allergic reaction to a peanut. And yet the conversation about guns among friends, neighbors and relatives has not become as routine.

While food allergies have been internalized as a public risk and childhood epidemic, the same cannot be said about guns.

More than 3,000 children and teens, up to age 19, are shot unintentionally each year on average, according to the Brady Campaign to Prevent Gun Violence.

In 2013, there were 108 accidental firearm deaths for those 18 years old and younger, according to data from the Centers for Disease Control and Prevention. The CDC does not specifically track peanut allergy deaths, but recorded 21 food-allergy-related deaths -- children and adults -- in that same year.

When looking at the totality of all firearm-related deaths for children and teens -- not just accidental ones -- the number is obviously much higher.

In 2010, there were 2,711 infant, child and teen firearm deaths. Writer Evan DeFilippis put this in perspective in an essay about the impact of firearms on children: "More American children and teenagers died from gunfire in 2010 -- a single year -- than U.S. troops in Afghanistan since 2001."

Has any parent ever asked me if we have a firearm in the house before entrusting me with their child? No. I've hosted countless children, and I've never been asked that question.

Catherine Mortensen, a spokeswoman for the National Rifle Association and mother of a 17-year-old daughter and 12-year-old son, says she and her husband have been gun owners since before their children were born. Their children have grown up shooting and are comfortable around firearms.

"I've never had a parent ask" about how their weapons are secured, she said.

But she wouldn't be offended if anyone did, she added. "I would tell them the truth: We do have firearms in the home. They are safely stored in a safe away from the children. They are inaccessible."

Becky Morgan of St. Louis also has two teenagers, and is the Missouri chapter lead for Moms Demand Action for Gun Sense in America. She said that recent high-profile news stories about accidental shooting deaths prompted her to ask the parents of her children's friends about firearms.

"You don't want to hurt anyone's feelings and you don't want to make anyone feel uncomfortable," she said. "But I would hate for something to happen, and I didn't ask because I was uncomfortable."

So far, every conversation she has had on the topic has gone smoothly. None of the parents she's talked to have owned a firearm, which makes the follow-up much easier for her. She said if she did encounter a family with guns in the house, she would ask to have the friend come visit at her home instead.

While the NRA says it's a personal decision for gun owners to decide how to store guns, they do advise keeping firearms "inaccessible to unauthorized users," Mortensen said.

The way to reduce the risk of children and teen gun deaths is to store guns unloaded and locked, and to store ammunition separately, also locked. And teach your kids these simple instructions if they ever encounter a firearm: Assume it's loaded. Don't touch it. Leave the area and tell an adult immediately.

The topic falls naturally into a wider conversation about safety concerns, said Danielle Alperin, program manager at the Brady Center.

"It's something we've found people kind of worry might be uncomfortable or awkward, but it could save a child's life," she said. Plus, their research found there's little if any resistance among gun owners to these questions. A responsible gun owner will want to tell you it's safely stored.

Once a parent has that information, it's up to them to decide how to act on it, depending on their comfort level, she said.

I've had to ask a close family member and longtime friends about their gun storage, after learning that the families owned guns. I do believe the people in my life who keep firearms in their homes are responsible adults who would do anything to keep their children, and my own, safe.

But I've decided that if I can casually ask about lethal peanuts, I can ask a few direct questions about a weapon designed to kill.