The study was compiled using National Center for Health Statistics data gathered from 2000 to 2009.
Suicides from falls or poisoning have risen and experts fear that there could be many more unaccounted for, reports the Daily Mail.
Ian Rockett, author of the study, told the Daily Mail: "I think the problem is much worse than official data would lead us to believe. We have a situation that has gotten out of hand."
Higher car manufacturing standards were credited for the decrease in deaths in car crashes, as well as stricter penalties for underage drinking and failing to wear seat belts.
Feijun Luo of CDC’s Division of Violence Prevention told Bloomberg News that a bad economy can cause more suicides: "Economic problems can impact how people feel about themselves and their futures as well as their relationships with family and friends."
"Prevention strategies can focus on individuals, families, neighborhoods or entire communities to reduce risk factors. Suicide is now the most frequent cause of injury deaths, followed by car crashes, poisoning, falls and murder."
In 2009, more than 37,000 Americans took their own lives. A suicide prevention program is being launched under the Garrett Lee Smith Memorial Act, which was signed by President George Bush in 2004, in memory of suicide-victim Garrett, son of former U.S. Senator Gordon Smith.