It can increase blood flow to the heart
There's one part of your body that's especially fond of laughter: your heart. According to the Cleveland Clinic, laughing immediately increases the blood flow to the extra-important organ, similarly to what happens when you're doing aerobic exercise.
Keep laughing
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Laughter increases your immunity
Negative stress causes chemical reactions in your body that decrease your immunity, making it more likely you will get sick. A hearty laugh fuels your immune system with disease-fighting powers that will help you stay healthy and energetic.
Laughter can reduce anxiety and other negative emotions
A 1990 study in Psychological Reports looked at the effects of humorous laughter on threat-induced anxiety. Laughter therapy has also been shown to improve anxiety in patients with Parkinson's disease, reduce anxiety and depression in nursing students, and improve optimism, self-esteem, and depression in menopausal women.
It's a good workout
Speaking of physical exercise, however, it's worth noting that watching stand-up comedy and laughing can be an easy workout, too. Of course, you probably shouldn't try to substitute laughing for a solid gym workout, but it does have its benefits. Studies have suggested that 10-15 minutes of laughing can burn about 50 calories. In addition to burning a few calories, laughing also works your stomach muscles by causing them to expand and contract. It also works out your shoulders and exercises the diaphragm and heart.