A pair of recent studies cast light on the effects of caffeine on the body. A report in the Archives of Pediatrics & Adolescent Medicine reveals African-American teens are at increased risk of hypertension due to caffeine in soft drinks.

The study, funded by the National Institutes of Health (Washington), offered 81 African-Americans and 78 Caucasians a sodium-controlled diet for three days, with six of the 15 drink choices containing caffeine. Young African-Americans who consumed the most caffeine (100mg) were found to have “higher systolic upper blood pressure readings than all other adolescents in the study,” the report found.

The other study of caffeine also promotes moderation. The Sleep Disorder Center at Rush University Medical Center (Chicago) investigated the best caffeine-consumption patterns for those who need to remain awake over a long period. James Wyatt, the laboratory director at Rush, notes, “Most of the population is using caffeine the wrong way--by drinking a few mugs of coffee or tea in the morning.”