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L-arginine: What You Need to Know


L-Arginine and Human Growth

If L-arginine stimulates protein production, especially creatine, shouldn't it be a natural choice to aid in human growth? Yes and no. We don't yet know -- or understand -- all the effects that L-arginine has on the body.

Arginine has been approved by the U.S. Food and Drug Administration to test for certain human growth disorders. In these tests, arginine is injected into the body. Its presence helps doctors detect the levels of growth hormones [source: Mayo Clinic].

L-arginine may boost the activity of certain hormones, including human growth hormone. But that's a big maybe. The ways in which L-arginine interacts with hormones are numerous and complicated. Estrogen may boost its activity; progesterone may suppress it [source: MedlinePlus].

There's a possibility that L-arginine can actually assist with human growth before birth. There haven't yet been enough studies to determine it conclusively, but it's possible that one day pregnant women will take supplements of L-arginine to aid in fetal growth, especially in cases of preeclampsia (a potentially dangerous condition in which the mother suffers high blood pressure during pregnancy) [source: Mayo Clinic]. Low birth weight is a major risk factor for infant mortality and numerous other health problems.

One interesting use of L-arginine is not so much to foster growth as to prevent wasting. In people with chronic wasting diseases such as HIV/AIDS, L-arginine seems to have the ability to help the body hang on to its muscle mass [source: Mayo Clinic]. Plummeting body weight can be a risk for numerous other conditions, and muscle loss can also mean a loss of independence. So L-arginine may help such patients' quality of life.

Ironically, even though it's touted as a bodybuilder's dream supplement, L-arginine gets a "D" rating as an exercise enhancer from the Mayo Clinic [source: Mayo Clinic]. So don't quit the gym just yet. In the quest for chiseled biceps and sculpted abs, there do not seem to be any shortcuts.

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