Doctor Q&A: Mel Heyman

Dr. Mel HeymanDr. Mel Heyman is chief of pediatric gastroenterology, hepatology and nutrition at UCSF Benioff Children's Hospital, as well as director of the pediatric gastroenterology and nutrition teaching program at the UCSF School of Medicine.

Heyman's medical research has revealed the importance of nutrition support in sickle cell anemia, helped develop procedures to diagnose liver problems in infants and investigated new treatments for children with inflammatory bowel disease and gastroesophageal reflux disease. Heyman co-authored a parent guide, "Feeding Your Child for Lifelong Health", with Susan Roberts, a professor of nutrition at Tufts University.

In the book, you talk about how the foods we feed our kids early on can affect them the rest of their lives through metabolic programming. Can you explain metabolic programming?

The example that we used in our book is switches on a railroad track, where the direction that the train takes depends on which switches you turn on and off. The foods that you eat early in life affect the 'switches' in our cells, which may influence growth, immunity, development, the endocrine system and intelligence — all these things that make up a human. What we hope is that, by starting somebody off right in life, you give them a better long-term outcome.

For instance, calcium is a nutrient that's important for building bones and teeth. You accrue calcium until your mid- to late twenties, and after that you lose it. If you can get more calcium into kids they'll have stronger bones later on.

What's the biggest mistake parents make in what they feed their kids?

Fast food is one of them. As kids get older they start going out to meals and getting in the fast food habit. Going out for meals is associated with increased weight gain.

Then you get all the sodas and other soft drinks, or even Gatorade, which is really a sugar drink. It's okay if the kid's out there running around on the sports field, but not as a snack food.

Juice is another big one. Kids are often given a lot of juice and it's unnecessary. The American Academy of Pediatrics recommends no more than four to six ounces of juice for children age 1 to 6, and no juice for kids younger than 1.

I was amazed how, in the book you mentioned parents would give kids soda when they're thirsty.

One of my colleagues, Janet Wojcicki, is heading a project where we follow a cohort of Latino babies long-term. She's found that there's a significant proportion of babies who are getting soda in the first six years of life.

What's the biggest mistake we make in how we feed kids?

One is pushing foods. I prefer offering healthy foods, letting the kids choose what they eat and being a good role model. If they see you eat the healthy foods they'll usually follow suit, although it may not happen right away. It may have to sit there for 10 meals before they finally start picking up the food.

I've always been very interested in how, if you let kids eat what they want to eat, they tend to eat enough to allow themselves to grow. For example, one of the big differences between breast-fed and bottle-fed kids is that bottle-fed babies tend to be heavier. One of the things we think is going on is that the parents look at the bottle and think, There's still milk left, my baby hasn't had enough. So they give them more. Whereas breast-fed babies drink as much as they need and the mother makes as much as the baby demands.

Kids are picky eaters, they will eat more or less at different times depending on their growth demands. They go through spurts and then slow down and then go through another spurt — that will affect how much they are eating at any particular meal. When kids get sick they tend to lose weight and regain it when they get well. Kids are pretty good at regulating that too.

Another potential mistake is that when new foods are introduced, it's important to give kids enough time to adapt to them. They may not want to eat it the first time — just leave it out there. If they're hungry and they realize that's what's left to eat, they'll often try it.

Portion size is another one. I think kids in the U.S. are used to bigger portion sizes than they are in other places. There's also a greater abundance of food or food types. It's been shown that if you have a lot of different foods in the household, kids will eat more than if there are fewer types of food.

Are most of your patients with nutrition problems suffering from allergies?

It varies. Allergies aren't nearly as common as people think they are. It's been shown that only somewhere between two to five percent of babies have a true milk allergy. If you listen to the public, it's going to be about 30 to 40 percent. The child is crying every night, and the parents blame the food. Then they restrict the diet for the wrong reason. They take all the milk out of the diet, for example, and the kid will be living on juice, which doesn't have adequate nutrition.

Are artificial sweeteners harmful for kids?

I used to be more concerned about that. I guess I've been convinced by my colleagues at the overweight clinic that probably the artificially sweetened drinks are safe. If you go through the research literature, there aren't any studies that suggest they do any harm. And especially if you have kids who drink soft drinks, at least they can shift to calorie-free drinks.

There were some studies a long time ago suggesting that NutraSweet could cause some changes in brain waves. But I think sweeteners like sucralose are relatively safe compared to some of the other artificial sweeteners that have been out there. I actually like the stuff, which drives some people in my family wild.

Lots of kids get stuck on carbs. What do you do if you have an older kid who only wants bread, pasta and sweets?

You can slowly introduce healthier foods, or you can mix some vegetables in with the carbs, and slowly increase the amount of vegetables and reduce the amount of carbs.

And if your child picks out the vegetables?

Just don't create fights over it and keep reintroducing the foods. You can cycle the vegetables so similar ones keep coming back — that way they don't seem 'strange.' Some kids will eventually learn to like them, and others won't.


Interviewed April 2009 by Sierra Tzoore.

Photo by Mark Estes.

Related Information

UCSF Clinics & Centers

Gastroenterology & Nutritional Disorders

Gastroenterology & Liver Practice
1825 Fourth St., Sixth Floor
San Francisco, CA 94158
Phone: (415) 353-2813
Fax: (415) 476-1343

More on the Expert

Melvin Heyman
Dr. Melvin Heyman,
pediatric gastroenterologist