Story highlights 130/80 is now considered high blood pressure, according to new guidelines

140/90 was previously defined as high blood pressure

14% more American adults are hypertensive than under previous guidelines

(CNN) Tens of millions more Americans now have high blood pressure. Almost half of all Americans -- 46% -- are now considered to be in the high blood pressure category based on new guidelines released Monday.

High blood pressure should be treated at 130/80 rather than 140/90, according to the new parameters set forth by the American Heart Association, the American College of Cardiology and nine other health professional organizations.

Practicing physicians and the public are "going to be a little bit shocked or taken aback by a diagnosis of Stage 1 hypertension with a blood pressure of 130/80, which historically has been considered a normal, well-controlled blood pressure," said Dr. William White, a professor in the cardiology center at the University of Connecticut School of Medicine.

"That will involve 50% of men and 38% of all adult women in the US," estimated White, who was not involved in writing the guidelines. "So it's a huge number of people."

One in three Americans had previously been diagnosed with the condition, but now 14% more Americans will be diagnosed with high blood pressure. The new guidelines will classify 103.3 million people as having high blood pressure, while the previous guidelines placed only 72.2 million Americans in this category, according to the authors of the report.

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