from the BUPA website:
Hot topic - Coughing? Take some chocolate
30 November 2004 - written by BUPA's Health information team
An ingredient found in chocolate may be a more effective remedy than current medicines for persistent coughs, according to a new study in the November 2004 edition of The FASEB (Federation of American Societies for Experimental Biology) Journal.1
What did the study show?
The study showed that an ingredient of chocolate called theobromine was more effective at stopping persistent coughs than the leading cough medicine codeine.1
What causes a cough?
A cough may be caused by a common cold or flu. This is because the throat and upper airways become reddened and swollen. The brain thinks that this swelling is an object in the throat and tries to remove it by coughing. Coughs caused by a cold or flu usually clear up quite quickly.2
What is a persistent cough?
A persistent cough is one that does not get better after more than two weeks. Sometimes, you may recover from a cold or flu but a cough lasts for longer.
Persistent coughing can be a symptom of other conditions, such as:
asthma
bronchitis
smoking
whooping cough
lung cancer
heart failure
pulmonary embolism (blood clot in the lung)
pneumonia
tuberculosis (TB)
How are coughs treated?
Cough medicines seem to work for some people, but there is still debate about if they are necessary or not.
There are different cough medicines for different types of coughs. Simple cough medicines line the throat and ease the irritation that causes coughing. They are generally safe.2
Codeine is a pain-relieving medicine that is used to treat severe coughs. It comes in the form of a tablet, liquid or injection.3
How was the study carried out?
Ten healthy volunteers were given theobromine, codeine or a placebo at different times. A placebo is a substance that doesn't contain any medication. The volunteers did not know which of the three options they were taking.
The volunteers were then asked to inhale a substance called capsaicin.
What is capsaicin?
Capsaicin is a substance that comes from capsicum (American pepper plants). It irritates the membranes that line all body passages that are in contact with air, such as the windpipe. Capsaicin is used in science research to cause coughing.1,4
How did researchers compare the effect of theobromine with codeine and placebo?
The researchers measured the levels of capsaicin needed to make the volunteers cough. Volunteers took either theobromine, codeine or placebo. They then took capsaicin to find out how much they needed before they started coughing.1
What did the levels of capsaicin show?
Volunteers needed to take more capsaicin after theobromine than after codeine or placebo.
The level of capsaicin needed to cause coughing was about one third higher in the volunteers who had been given theobromine compared with placebo.
Those who were given codeine only needed slightly higher levels of capsaicin than those given the placebo to cause a cough.1
Did theobromine have side-effects?
No. The volunteers who took theobromine had none of the side-effects normally caused by other cough medicines.
What side-effects do other cough medicines have?
The majority of cough medicines have very few side effects. Codeine and cough medicines that contain antihistamines may cause drowsiness, constipation, difficulty passing urine, dry mouth or blurred vision.2,3
Check with your GP or pharmacist before taking cough medicines. People with diabetes should avoid cough medicines that are sugar based.
Why is theobromine better than other cough medicines?
If research confirms that theobromine does not cause drowsiness, then there may be no limits on when theobromine can be taken. For example, people who take codeine must make sure their reactions are normal before driving or carrying out any jobs that need them to be fully alert, since codeine may cause drowsiness.
The researchers suggest that the lack of side-effects may mean that theobromine could be given at higher doses than other cough medicines.1
How much theobromine did volunteers take?
The volunteers were given a dose of theobromine that was equal to the amount of the ingredient found in a 50g bar of dark chocolate or two cups of cocoa.1
Why does theobromine put a stop to coughing?
Theobromine suppresses the activity of the vagus nerve, which causes coughing.1
What did the study conclude?
The researchers concluded that theobromine is a promising new treatment, which may form the basis for a new type of medicines that can relieve or prevent coughing. More research is needed to fully understand these findings.1
Should I eat chocolate if I have a cough?
According to this study, theobromine, which is a key ingredient found in chocolate, may be effective at stopping persistent coughs.
This was a very small study and more research is needed to fully understand the findings. If you have a persistent cough, you should speak to your doctor before switching your cough medicine for chocolate.1
What can I do to help relieve a cough?
sip hot honey and lemon drinks
don't smoke and avoid smoky places
use extra pillows at night to raise your head
inhale steam, eg from a bowl of hot (but not boiling) water
take a hot bath or shower to expose your chest to steam