Why laughing often and listening to music can lower blood pressure

　　In a study lasting three months, researchers from Japan's Osaka University divided 79 people aged 40-74 into three groups and then tested them every two weeks. People in group 1 had to listen to music for an hour; people in group 2 had to find ways to laugh; and people in group 3 did nothing. Before and after the experiment, the researchers measured their blood pressure.

　　The results showed that after listening to music, the blood pressure of the people in the music group was 6 mmHg lower than before listening to music; the blood pressure of the people in the laughing group was 7 mmHg lower after laughing than before laughing; while the blood pressure of the people in the control group did not change.

　　Researchers explain that listening to music or laughing can have the effect of lowering cortisol levels in the body, thereby lowering blood pressure. Cortisol is the basic stress hormone. Under stress, the human body needs cortisol to maintain normal physiological functions. However, continued exposure to excessive stress can make cortisol levels too high for a long time, leading to increased blood pressure.

　　However, the researchers pointed out that although listening to music and laughing can help lower blood pressure, there is no causal relationship between the two, and further research in this area is needed.