Americans love salt and ingest much more than the recommended one teaspoon a day.
"We are eating more than 10 times that amount," said Annet Kirabo, Ph.D. with Vanderbilt University Medical Center.
Excess salt flips an internal switch, leading to hypertension and cardiac disease.
"If anyone eats high salt for a long period of time, they're likely to have their kidneys damaged, and they're likely to have increased blood pressure," she said.
Hypertension patient Aaron Finley works in customer service and is a part-time actor. He recently found he is in two high-risk groups: Older African-Americans and a group called highly-sensitive to salt.
"I was predisposed to getting it just with my lifestyle," Finley said.
In a study, Kirabo and her team continually measured blood pressure while participants were administered either a restricted salt diet or one very high in salt. They discovered just one salty meal can set it off.
"You can go to a doctor, and the doctor tells you you don't have high blood pressure, and yet, you go home and eat a salty meal and get a stroke or get this dangerous increase in high blood pressure," said Kirabo.
It can also cause cell and tissue damage.
"Corresponding to salt intake is a rapid increase in inflammation caused by oxidative stress and oxidation of lipids," she said.
Reducing salt, exercising and staying active and involved with others helps, but most important - is knowing if you have high blood pressure.
"To know is better than not knowing because when you don't know and you find out, it could be catastrophic," said Finley.
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