Kids' Health

This Is How Gut Bacteria Affects Your Kid’s Behavior

Eat veggies and chill.

by Jonathan Stern
Originally Published: 
mental health

Medical research is finding that the stomach isn’t just the way to your heart, but also your mind. No doubt you’ve seen articles touting the gut/brain relationship everywhere. But wouldn’t you rather trust a doctor who has applied this science to their own kid? Dr. Vincent Pedre is an expert on the subject of gut health, author of the new book Happy Gut, but most importantly he’s a father who got his son to like salad!

How The Belly Connects To The Brain

The first thing you should know is all the good bacteria (aka probiotics) in the world won’t stop a toddler from throwing a tantrum in the middle of a crowded restaurant. Activia doesn’t cure being 3. But when you promote a diverse microbiome (that’s your community of good bacteria — like a Mr. Rogers’ Neighborhood for gut health) it affects the neurotransmitters like serotonin (which just happens to be the Mr. Rogers of brain chemicals).

“It’s a chain of command,” says Dr. Pedre “We see the connection from what you’re eating in the diet, to what type bacteria are living in your gut, and how that bacterial community is interacting with each other and then producing a product, a short-chain fatty acid called butyrate. That gets absorbed, goes to the brain and affects gene expression.”

Those veggies you’re giving your kid contain a prebiotic (the food for probiotics) called inulin. Veggies like asparagus, garlic, and onions have this fiber. That Inulin feeds the probiotics in your gut. Those probiotics cross-feed other bacteria that promotes butyrate-producing colon bacteria. That butyrate tells your DNA, which is wound up like a scroll, to open. Then your brain reads that scroll and allows the body to do all sorts of amazing things, like control inflammation, create long-term memory, and become green and super-strong (don’t laugh — it worked for the Hulk’s cousin).

Breaking Down the Blood Brain Barrier

Everybody has this layer of small vessels, like capillaries, that protects your brain from toxins. They can be environmental (like from the Thneed factory down the street) or just other strains of bacteria that find their way into the body. Kids are especially vulnerable because they haven’t built up this barrier of protection yet. So, part of keeping toxins out of the brain involves having more good bacteria than bad coming from your intestines. If your child still won’t eat his veggies based on that explanation, maybe a screening of The Toxic Avenger is in order.

Your Gut Is Leaking

One hypothesis about why what we eat goes straight to our heads is due to “leaky gut syndrome.” That’s where those aforementioned toxins escape your intestines, travel through your bloodstream, and are attacked like a foreign invader. If anyone has told you they’re “gluten free” this is the reason.

Sugar Speeds Them Up

One food that is indisputably the king of crankiness is sugar. Dr. Pedre says, “What’s going to influence behavior, especially what’s going to make them hyper is too much sugar in the diet. What’s happening in the background when you’re eating a lot of sugar is that it’s feeding the gut microbiome, but it’s favoring a certain type of microbiome, probably producing chemicals that aren’t favorable to brain health.”

Gluten Slows Them Down

Nobody is trying to take away your unlimited breadsticks and the never-ending bowl of pasta. But those with irritable bowel syndrome or Celiac disease can trace many of their troubles back to foods high in gluten. “Both gluten and dairy produce morphine-like substances that go to the brain, and it dumbfounds the brain,” says Dr. Pedre. Gluteomorphin, one chemical component of gluten, is blamed for that doped-up feeling.

Some Common Mistakes Parents May Be Making

  • Too much Go-Gurt. Dr. Pedre says, “It’s wrong to think that eating a sugar-loaded yogurt is the equivalent of getting a healthy dose of good bacteria. The fact that it’s full of sugar outweighs the benefits of having had the yogurt in the first place. I have my patients make their own yogurt or drink kefir, which has a higher concentration of good bacteria.”
  • Not enough veggies. Eat a lot of different fruits and vegetables. They contain fiber and inulin — that food (or prebiotic) for the probiotics. “All vegetables have benefits to some extent. Some are richer in soluble fiber, like apples, berries, and oatmeal. You also want insoluble fibers, like leafy greens, asparagus.” The most super of prebiotic-rich foods? The Jerusalem artichoke, which your local lunch lady may find too political.
  • Buying the wrong probiotics. Check the label for the CFU count, which stands for colony forming unit. “A billion sounds like a lot,” says Dr. Pedre, “But when it comes to the gut it’s a drop in the bucket. It’s estimated there are 100 trillion bacteria in your gut. Sometimes I have patients on 200B strength probiotics.” He also recommends trying multiple strains, because one may work where another does not.
  • Using anti-bacterial soap. Along with the flu germs and staph strains, your child is also washing off all the good flora that is going to boost their gut health. Regular hand soap without triclosan is good enough to get clean.
  • Not getting dirty enough. A study found that kids who played in the dirt did better at school than those who just had access to concrete schoolyards. So if you catch them serving a dessert of mud pies to their friends, turn your head.

How Foods Affect His Own Son

Dr. Pedre has been where you are. His son started having behavior problems in kindergarten, and he suspected that a gluten sensitivity was the culprit. They took away his sandwiches and starches, and within a week his behavior changed.

“It was really dramatic,” he says. “We had him off gluten for a while, but one time we went out for pizza on vacation. I wasn’t going to deprive him of pizza! His personality changed immediately. He got all glassy-eyed and tired.”

This story does have a happy ending, though. Dr. Pedre says that his son, now 11, can eat pizza once in a while — which is better than no pizza at all.

If you’re on the fence about how to fix behavior issues, switching to a gut-healthy diet (more veggies, less sugar and carbs) for a week to see if something happens is far less extreme than psychotropic drugs. “Kids respond really fast to a diet change. It may be torture for a parent — but you’re going to have to be willing to go through an uncomfortable stage knowing you’re doing the greater good for your child.” Sorry guys, looks like “C” is now for “cabbage.”

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