Football, baseball, field hockey, swimming, basketball, and cross-country are just a few of the competitive sports high school students play. And just like adult athletes, they’re looking for an edge. With ads for protein powder everywhere and drool-worthy protein-shake recipes on every health blog, it’s unsurprising that some teens are trying protein supplements to boost their game.

And protein powders have attractive benefits. Protein is made up of essential amino acids, which are the building blocks of muscle. In one study, men using resistance training to build muscle were given either a protein supplement or a placebo. The group that took the protein supplement saw bigger gains in total body mass, fat-free mass, thigh mass, and muscle strength.

Excess protein in teens can cause kidney problems if they’re drinking too many shakes that contain the amino acid creatinine.

And there are many other studies with positive results.

But most protein powders have a warning like this somewhere on the packaging: “Intended for Healthy Adults over the Age of 18.” What happens when you ignore the fine print?

The truth is that no one’s sure what happens. Protein shakes and supplements aren’t regulated by the FDA, and when their effects are studied, most trials are performed on adults. The Institute of Medicine’s recommended daily allowance (RDA) of protein for teens is 34 grams for 13-year-olds, 46 grams for 14-18-year-old girls, and 52 grams for boys in the same age group.

A popular whey protein powder contains 24 grams per scoop. A 13-year-old who has one scoop of protein powder (24 g), a glass of 2 percent milk (8 g), and a hamburger (18 g) by lunchtime has already had 16 g more than her RDA. And she still has to eat dinner.

Related: Teens and the Caffeine Danger

It’s hard to get too much protein eating a balanced diet, but excess protein in teens can cause kidney problems if they’re drinking too many shakes that contain the amino acid creatinine. They may also lose calcium from their bones because our bodies leech calcium into our bloodstream to combat the acidic pH caused by excess protein.

Something else to consider about whey protein powder is that it contains high amounts of lactose. You may think that you’d know if you were lactose-intolerant, but researchers think that about 60 percent of people lose their ability to easily digest milk sometime after childhood. Some of these people have obvious symptoms, and others may have mild symptoms that they never connect to drinking milk or eating dairy. But whey has a lot of lactose, enough to set off symptoms like stomach cramps in anyone who’s sensitive to it.

The healthiest way for teens to get extra protein is from their diets.

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And then there’s what’s not on the ingredients label. A 2013 consumer report cautioned that more than half of recent drug-related recalls have been for dietary supplements. Contamination with dangerous chemicals was the most common reason for these recalls, and most of the contaminated products contained chemicals that act as hormones in the body. The unintended use of hormones can wreak havoc on adult bodies, causing facial hair in women and breast growth in men. The risks to a teen still going through puberty are unknown.

There have also been cases of protein supplements containing illegal steroids and heavy metals like arsenic, cadmium, lead and mercury.

The healthiest way for teens to get extra protein is from their diets. Even athletic teens trying to put on muscle can get all the protein they need from a combination of lean meats, eggs, dairy, fish, nuts and seeds.

Related: Foods to Buy, Foods to Beware

A Greek yogurt-based shake with a few tablespoons of chia seeds and some frozen fruit is a whole-food source of 22 grams of protein. And when you get your protein from whole foods, you’re also consuming the vitamins, minerals, and healthy fats your body needs to do its job. As always, consult with your doctor before using any supplements.

Dr. Manny Alvarez serves as Fox News Channel’s senior managing health editor. He also serves as chairman of the department of obstetrics/gynecology and reproductive science at Hackensack University Medical Center in New Jersey. This Fox News article is used by permission and also appeared on AskDrManny.com. 

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