Studying for the SAT? The best test-prep could be in your blood.
Lead levels in children's blood exhibit a strong correlation to their SAT scores and mental capacity later in life, a new study shows.
The rise and fall of lead levels in children almost directly mirrors the fall and rise of their SAT scores over the past fifty years, study author and economist Dr. Rick Nevin found.
Nearly half of the change in the national average SAT score can be attributed to variations in lead in the blood, the study says. Sixty-five percent of the fluctuation of the math score and 45 percent of the verbal score are direct results of lead, the study said.
Long-term mental retardation is also a result of lead in the blood - the lower the lead level as a child, the less likelihood of mental handicaps down the line.
The study suggests that natural factors affect student performance as much as what they learn in school.
"It shows these kids are mentally handicapped from the start," Bob Schaeffer of non-profit testing watchdog FairTest told USA Today.
The study is available to read in the Environmental Research Journal online.