Laughing Extends Blood Vessels
By Marietta Gross - Scoop Media Auckland
The old sage advice that laughing is good for one’s health has again been proven to be true, this time with the aid of
the cinema. After consuming comedies on the big screen, stage, or television blood vessels of those studied were charged
with oxygen. Those who indulged on war movies proved to have no benefit at all.
Laughing seems to extend the inner tissue of blood vessels which results in better blood circulation, reports cardiac
surgeon Michael Miller from the Medical Centre of the University of Maryland and American Cardiac Association.
The study examined the behaviour of 20 non-smokers after watching different movies. The gender ratio of the test was
balanced equally. The average age was 33 years. The University of Maryland stated the films chosen lay at the contrary
“ends of the spectrum of emotions”.
For example the extremes provided mental stress in connection with movies like “Saving Private Ryan”, in which the
fortune of an US soldier during the Second World War is (gorily) constituted. On the other hand extracts of comedies
were shown, for example “King Pin” from the year 1996, which appealed to the laughing muscles.
Before the tests started the blood circulation of the upper arm artery was analysed. The subjects then viewed extracts
of movies in a constantly tempered room. Then again the reaction of the blood vessels was examined.
The results: While watching the films, there were no recognisable changes to the blood vessels. But afterwards
significant differences appeared. The blood circulation of the upper arm artery of three quarters of the war movie
watchers was reduced. In contrast 19 of 20 comedy watchers showed an extension of their blood vessels.
According to the scientists the average blood circulation rose by 22 per cent after laughing and declined by 35 per cent
after suffering from mental stress. The changes within the blood vessels could be proved up to 45 minutes after the end
of the movie. It didn’t matter if the subjects knew the films before or not.
Michael Miller compares the effect of laughing with physical training and aerobic exercise. Periodical laughing could
not substitute a work out at the gym, but “… half an hour training three times per week and a daily dose of laughing for
quarter an hour” would be ideal for the blood vessels.
Miller is silent on how exactly the mechanism works, and laughter extends the blood vessels. But he says one possibility
is the reduced production of nitric oxides when mental stress occurs – and these play an important role for the
stricture or extension of blood vessels.