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Can you eat too much of a healthy food?

Let’s take a look at a few beverages and foods that may cause more harm than good if taken in excess.

Eating healthy is a good thing, right?  Well, think again.  We always hear that eating a variety of foods in moderation is best, but what happens if your child eats a healthy food in excess? Let's take a look at a few beverages and foods that may cause more harm than good.


I often hear parents say, my child is a picky eater, but I can get them to drink milk.  Milk can be a great source of calcium and vitamin D.  But drinking too much milk can increase your child's risk of developing iron deficiency anemia.  Milk is low in iron and it also inhibits the absorption of iron in the body, which may lead to IDA.  Kids who drink too much milk also limit their diets by not eating from other food groups.

How much is too much?  Most toddlers and older children should drink no more than 2 to 3 cups of milk a day to meet their calcium and vitamin D requirements, according to the United States Department of Agriculture. Using, Choose My Plate, can help you find calcium rich foods including how many servings your child needs daily.


As a nutritionist, I always encourage kids to eat more fish as good source of lean protein and healthy fats, but should we be worried about eating too much? Most fish contain trace amounts of mercury,  an environmental contaminant.  If kids eat large amounts of fish, the levels of mercury can be large and toxic causing neurologic problems such as vision changes and learning impairments. This toxicity is rare and can be avoided by eating the right amount of fish weekly.

What are the recommendations?  Most school-aged kids should eat 4- ounces and teens should eat 8- ounces of fish and seafood per week, according to the 2015 Dietary Guidelines.  The U.S. Food Drug Administration recommendations include to avoid the four fish with the highest levels of mercury: shark, swordfish, king mackerel, and tilefish.  Albacore "white" tuna should be eaten only once week, but eating light, canned tuna is OK to eat since it is low in mercury.

Brazil nuts

I can't say that I hear kids eating too many Brazil nuts, but even if a 2-year-old eats more than three or four nuts every day, this may lead to getting too much selenium over time. Selenium is a nutrient found in seafood, meat, eggs, whole grains and dairy products, which is important for fertility, a healthy immune system and cognitive function.  A deficiency is rare, but getting too much selenium can cause diarrhea, irritability, brittle hair or nails, nausea, and nervous system problems.

How much is too much?  Selenium recommendations range for young children to teens, 90-400 mcg, respectively, According to the National Institutes of Health. One Brazil nut contains approximately 68-91 mcg, so eating too many Brazil nuts can increase the risk of a toxicity.

Take home message

The foods on this list are healthy in small amounts, but it doesn't mean that large amounts are healthier.  Teaching your kids to eat a variety of foods in moderation is the key to healthy eating.  Eating too much of even healthy food can be harmful.

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