October 18, 2009, Updated September 14, 2012

An Israeli physician finds that athletic teenage boys may be at serious risk for iron deficiency, but once identified, it’s a condition that is easy to remedy.


Parents and health counselors already know they need to keep an eye on their teenage girls’ health and eating habits. At risk for anorexia and bulimia, today’s girls watching TV shows like The Hills (the partially-scripted reality show about young women living in LA) feel pressured to look Hollywood-thin.

But active boys in college football, finds new research from Israel, are in an at-risk league of their own. According to Dr. Drorit Merkel, a physician from the Chaim Sheba Medical Center in Israel, athletic teenage boys are at a serious risk for iron deficiency, and they probably don’t even know it.

Iron deficiency is like kryptonite to these athletes, and many could boost their endurance, concentration and play with a simple change in diet, or an iron supplement.

Merkel’s conclusions come after a long chain of studies she conducted measuring nutrition in soldiers in the Israel Defense Forces and in studies she completed with the US Army. Her recent report, published in the multi-disciplinary journal Adolescent Health, found that after periods of intense physical exercise, iron deficiency rates in athletes can almost double, and anemia rates even more so.

In half of the new cases of anemia found in her study, new-onset anemia could be associated with iron deficiency. While doctors can test for anemia – not uncommon in teens, who sometimes seem to grow more quickly than their bodies can catch up – iron deficiency is something that won’t register on a regular blood test, and often doesn’t present symptoms, Merkel tells ISRAEL21c.

Finding the cause of that run-down feeling

Athletes are in a special class. They’re at risk of sports anemia, which appears after intense physical exercise, especially in new and endurance athletes, or those who suddenly increase their training regime. While the condition is generally considered to be short-lived according to online reports, Merkel suggests that all active teenage boys get a test for iron deficiency.

Normal healthy teenage boys usually don’t have anemia, and if they had an iron deficiency, they wouldn’t know it. But athletes are different: “They are not feeling weak because they are well trained,” she tells ISRAEL21c. “They could just continue [playing] and feel they have to do better.”

What this means is that if your boy or the coach’s star player is not playing his best, no one would necessarily know why. But iron supplements, red meat or turkey could boost energy levels and performance in the short term, Merkel advises.

While long-term effects of iron deficiency are not conclusive, Merkel speculates that they could reduce the body’s ability to remove toxic heavy metals. Over time, a lack of iron may also increase the rates of bone fractures. But this possibility, she stresses, has not been proven.

Endurance and concentration may be affected

“There is no good information about the long-term effects of iron deficiency,” says Merkel. “For some reason there is more absorption of heavy metals, but it’s not well established.

“We don’t really know about the long-term, but we do know that in the short term, endurance is going down. If you check long [distance] running, they can run less. Their ability to study and concentrate is reduced too.”

Working with data collected from young men serving in an elite army unit in Israel, Merkel examined 153 18-year-old boys and found that 17.6 percent were already anemic prior to a six-month training period. These initial high rates seem to point to the boys’ pre-training period, the time before they earned a spot in their unit.

But what happened over time interested the investigators most: Rates of anemia nearly tripled within six months (from 17.6 to 50.3%) and it wasn’t the only effect Merkel measured. Iron deficiency, which often doesn’t show up in a routine blood test, nearly doubled from approximately15% before the study, skyrocketing to 24.5%.

Multiple causes, simple solutions

According to Merkel, there are a number of reasons why teens may suffer from anemia, a condition that is exacerbated by playing sports. The intestine appears to suffer from bouts of ischemia (blood flow restriction) during intense endurance activities. Blood flow is concentrated in the brain and extremities, and doesn’t reach the kidneys or intestines.

And sports-related inflammation prevents iron from being absorbed properly, she reasons. A multitude of factors appear to be at play here, for something that can be easily diagnosed and treated with a blood test and change of diet.

Merkel’s concern as a hematologist is borne out by the fact that many of the boys at risk may test positive for anemia, but will not show iron deficiency. Some goods news is that a past study of the doctor’s found that those taking iron supplements became faster at their specific pursuit.

For boys who are athletes or who are in physically demanding units in the army, she advises that doctors perform a blood test for iron deficiency once or even twice a year. Iron supplements, she warns, should be prescribed by a doctor.

Merkel’s findings should motivate parents to woo back their college football stars for homemade meals. Gathered round the turkey on Thanksgiving might be the very moment to bring up the topic – just in time for your star athlete to wow the cheerleaders and scouts at the biggest games of the season.

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Jason Harris

Jason Harris

Executive Director

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