Scuba divers may want to take some vitamins before jumping into the water.

A new study in the Journal of Physiology finds that divers can protect themselves from some of the blood vessel impacts of diving by taking vitamins C and E two hours before a dive. The vitamins seem to help because they are antioxidants, the study authors write.

The oxygen tanks scuba divers use underwater expose their blood vessels to high levels of oxygen. When the divers return to the surface, this exposure can leave their blood vessels dilated and can impair the lining of their arteries for days afterward, they write.

All it took was a single dose of vitamin C powder (2 grams) and a dose of vitamin E (400 international units) to mitigate the effects.

What the vitamins didn't help, the authors report, was the decrease in lung function and heart output that can be caused by scuba diving. These effects lasted for at least a few days in the divers participating in the study.

Lavender, tea tree oil expose boys to estrogen

Products containing lavender and tea tree oil may in rare cases cause prepubescent boys to grow enlarged breasts.

A study in the New England Journal of Medicine last week examined three case studies of boys ages 4 to 10 who had mysteriously grown breast tissue similar to that of a girl in early puberty.

None of the boys had elevated estrogen levels in their own bodies, so the doctors wondered if they were being exposed to estrogen from something outside their bodies.

They discovered that one of the boy's mothers had been applying a salve to his body that contained lavender, another boy was using hair gel and shampoo that both contained lavender and tea tree oil and the third boy had used lavender-scented soap and lotion. All three boys got better when they stopped using the products.

The doctors investigated and found that both lavender oil and tea tree oil appear to act as endocrine disrupters: They have weak estrogenlike effects and slightly counteract the effects of the male hormone androgen.

Soccer injuries rise with sport's popularity

More kids playing soccer means more soccer injuries, according to scientists at Columbus (Ohio) Children's Research Institute.

They found 1.6 million children visited emergency departments with soccer-related injuries in the United States from 1990 to 2003. Hand, wrist and finger injuries were the most common reason for the visit, followed by ankle and knee injuries. Boys were more likely to have serious cuts or punctures and to be injured in the face, head or neck. Girls were more likely to have sprains or strains of their ankles or knees.

The data were taken from the U.S. Consumer Products Safety Commission's database of emergency department records. The findings appear in the current issue of the American Journal of Sports Medicine.

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Julie Kirkwood's Health and Science Journal runs in Health North on Mondays. She can be reached at 978-946-2251 or jkirkwood@eagletribune.com.