PROVO, Utah, March 20 (UPI) -- Men and women in happy marriages have lower blood pressure than single people, but unhappily married adults have higher blood pressure, a U.S. study said.
Julianne Holt-Lunstad of Brigham Young University found that men and women in happy marriages scored four points lower on 24-hour blood pressure than single adults.
The researchers had 204 married and 99 single adults wear portable blood pressure monitors for 24 hours.
The study, published in the Annals of Behavioral Medicine, also found that unhappily married adults have higher blood pressure than both happily married and single adults.
However, the study found having a network of supportive friends did not translate into improved blood pressure for singles or unhappily marrieds, which Holt-Lunstad said surprised the researchers.
"There seem to be some unique health benefits from marriage," Holt-Lunstad said in a statement. "It's not just being married that benefits health --- what's really the most protective of health is having a happy marriage."
The researchers found blood pressure for married adults -- especially those happily married -- dipped more during sleep than happens with singles.
"People whose blood pressure remains high throughout the night are at much greater risk of cardiovascular problems than people whose blood pressure dips," Holt-Lunstad said.