Home > Mental health > News Updated 13 December 2013 Laughter can be dangerous to some people Laughter may not be the best medicine after all and can even be harmful to some patients. 0 iStock Related Laughing yoga cultivates merry mindfulness Teaching the brain to process laughter Animals on a trampoline Ask CyberShrink » Talk Heart to heart forum » 13 hidden signs of stress Regenerative medicine: replacing brain cells lost from stroke Researchers from Birmingham and Oxford, in the UK, reviewed the reported benefits and harms of laughter. They used data published between 1946 and 2013. They concluded that laughter is a serious matter.They identified benefits from laughter; harms from laughter; and conditions causing pathological laughter.Some conditions benefit from 'unintentional' (Duchenne) laughter. Laughter can increase pain thresholds although hospital clowns had no impact on distress in children undergoing minor surgery (even though they were in stitches). Laughter reduces arterial wall stiffness, which the researchers suggest may relieve tension. And it lowered the risk of heart attack, so "reading the Christmas BMJ could add years to your life".Clowns improved lung function in patients with COPD and 'genuine laughter' for a whole day could burn 2000 calories and lower the blood sugar in diabetics. Laughter also enhanced fertility: 36% of would-be mothers who were entertained by a clown after IVF and embryo transfer became pregnant compared with 20% in the control group.Adverse effects of laughterHowever, laughter can also have adverse effects. One woman with racing heart syndrome collapsed and died after a period of intense laughter and laughing 'fit to burst' was found to cause possible heart rupture or a torn gullet. A quick intake of breath during laughing can cause inhalation of foreign bodies and can provoke an asthma attack. Laughing like a drain can cause incontinence. And hernias can occur after laughing: rapture causing rupture.The authors' list conditions that cause pathological laughter and this may help in diagnosis. Epileptic seizures ("gelastic seizures") are the most common cause.The researchers say that their review challenges the view that laughter can only be beneficial but do add that humour in any form carries a "low risk of harm and may be beneficial". They conclude that it remains to be seen whether "sick jokes make you ill, dry wit causes dehydration or jokes in bad taste [cause] dysgeusia (distortion of sense of taste)". EurekAlert NEXT ON HEALTH24X 'The plane is going to crash': Anxiety aboard flight SAA 323 2017-10-17 07:45 More: Mental healthNews advertisement Read Health24’s Comments Policy Comment on this story 0 comments Comments have been closed for this article. Logout Comment 0 characters remaining Share on Facebook Loading comments... Other news Lifestyle 3 foods you must eat if you’ve ever smoked Mental health Why some people freak out about belly buttons Medical 'Dead' man snores back to life right before his autopsy Fitness What's the deal with pain after exercise? Fitness 10 triathlon mistakes to avoid Fitness 5 reasons you shouldn't exercise with headphones From our sponsors Managing diabetes in the workplace Back-to-school with diabetes Discover treatments that can help reduce acne What can I do to reduce or remove acne marks? Live healthier Fact or myth? » Clearing up the confusion around coconut oil Coconut – the 'fruit of life' Can coconut oil really help you lose weight? Experts dish on the high-cal weight-loss tactic. Sobering perks! » 5 tips to avoiding a hangover Can you really be allergic to alcohol? Is giving up booze for a month actually worth it? Many people commit to "Dry January" – but does it do your body any good?