What doctors say*
* Official guidelines from NICE, NHS and other medical authorities.
Should antibiotics be used? >
No. Colds and other viral infections do not respond to antibiotics.
Likely duration if untreated >
Conventional selfcare advice >
- Keep warm
- Drink adequate fluids
Opportunities for antibiotic alternatives >
In almost all cases
There is increasing clinical trial evidence that mushroom supplements (containing β-glucans and other immunoactive constituents) reduce the incidence and severity of respiratory tract infections. The main species studied are reishi (ganoderma), shiitake, and maitake mushrooms. Yeast supplements may also be considered and are generally more available.
It is wise to choose a reputable supplier rather than buy indiscriminately on the internet.
In theory some of the benefits of supplements may be obtained by eating a range of mushrooms in the diet. However there is no direct evidence for this.
Polyphenols, such as flavonoids and anthocyanidins, are very common constituents of plants, fruit and vegetables, especially those that are coloured. Supplementation with polyphenols has been shown to shorten the duration of colds and viral infections. High natural sources of polyphenols are red grapes (and red wine), cocoa, and pomegranate.
In research studies of mixed quality, various probiotic supplements, especially containing strains of Lactobacillus and Bifidobacteria, have been shown to reduce the frequency, duration and intensity of respiratory infections, especially in children.
All these benefits were seen after at least several weeks consumption of these probiotics and it is less likely that short term use will have much impact. Probiotics may therefore best be seen as preventative rather than as treatments.
There is good quality evidence that vitamin D supplements can reduce the risk of catching colds or other respiratory infections.
Regular dosing is more effective than taking the vitamin intermittently and benefits will be felt most by people who are depleted in the vitamin. However in Britain and other urban cultures and where there is less exposure to sunlight, vitamin D deficiency is quite common.
In one clinical research study flu symptoms were relieved earlier in subjects taking elderberry syrup than those taking placebo syrup. In another an elderberry extract reduced the duration of common cold.
Elderberry syrup and supplements are readily available. It is advised to choose products from reputable suppliers rather than indiscriminately over the internet.
It is also possible to make your own elderberry syrup at home by wildcrafting the berries from hedgerows in the autumn.
Although the evidence is mixed it appears that moderate levels of exercise can reduce the risk of catching colds or other infections.
Too much exercise is well known to expose athletes to more infections and too little appears to do the same.
Some proprietary garlic preparations may both reduce the risk of respiratory infections and the symptoms when they happen. Raw garlic is the traditionally favoured option, often in high doses, although this does not have modern research evidence, and also has social consequences!
There is moderate evidence that reducing stress and improving relaxation will increase resistance to colds, flu and other respiratory infections.
Self-taught mindfulness, meditation, or simple hobbies and restful activities like gardening, fishing or raambling are likely to be as least as effective as formal classes in meditation, yoga or tai chi. The method is only as good as its application.
Rubbing mentholated and other aromatic vapours onto the chest or near the nostrils is a very familiar approach to relieving congestion. There is some evidence of benefit from this approach at least in children.
Doses of vitamin C of greater than 200mg have been shown to shorten the duration and severity of colds. This benefit was however most likely in people exposed to physical hardship of extensive exercise or extremes of cold (both increasing oxidative stress in the body), or deficient in vitamin C.
Benefits were only seen after longterm use and vitamin C should thus be seen as a preventative rather than a treatment.
As a supplement there is some evidence that the equivalent of 15-30mg ‘elemental’ zinc can reduce the duration of colds in children.
Zinc lozenges (as opposed to syrup or tablets) have a notable bad taste and can induce nausea.
Traditional home remedies worth trying
Eating fresh raw garlic has long been a favoured remedy for colds and coughs. The case for this is supported by the antiseptic properties of the odorous component of garlic, and the fact that this is excreted from the body partly through the airways (hence the social problems!). Rather than take raw garlic though the working day and threatening one’s relationships, another option is to take it in one go, perhaps on a Friday evening before a weekend, and to use the opportunity to take as much as you feel comfortable with.
The best way to proceed is to take one clove off a head of garlic, peel it, chop it finely and swallow with a little water (no need for chewing). Half an hour later, when it is clear your stomach is happy with this, repeat with another clove, and then again until you have taken many more. Some people cannot take much garlic in this way but any discomfort will be temporary only and will be limited by this slow pace of dosing. If however you do feel discomfort it is best not to proceed – the stomach is the boss here. Many can happily take eight or more cloves at a time.
Common experience that a day or so later there is a significant reduction in many symptoms of colds and coughing.
Consistent advice in managing colds is to keep you or the sufferer warm (though see also ‘Fever management’). At the first onset of chills it is natural and useful to take hot baths, have hot drinks and tuck into warm clothes or bed. It is also possible to add internal heating in other ways. The hot or warming spices such as cayenne, ginger and cinnamon are known to increase heat generation (‘thermogenesis’) and have long been used in fever management from ancient times.
There is a simple home remedy that provides all the benefits of spices in colds and flu. It is ginger and cinnamon tea. This tea will immediately counteract any symptom made worse by cold or improved by heat. It could be an actual cold, or a headache or pain that improves with a hot water bottle or hot bath. The tea triggers a reflex increase in blood flow to the mucous membranes of the mouth, airways and gut, and then elsewhere around the body.
As soon as you feel cold or a cold coming on, take
- one knob of fresh ginger (about the size of your thumb) freshly grated
- a teaspoon of powdered cinnamon (best if freshly ground)
Add to a large mug and pour on boiling water. Stir, seep for 5 minutes or so, strain and sip. If this is helpful you may wish to make more and keep it in a vacuum flask for sipping through the day.
Knowledge and best practice in the health field are constantly changing. Each person and illness is also unique and no general information can anticipate every circumstance, nor be appropriate for every reader. Each individual case is best assessed in person by a qualified health advisor.
In the case of remedies or other products, users should read the label carefully for detailed information about safe use and in the case of natural products should choose responsible manufacturers with independently assured quality standards and safety monitoring procedures.
To the fullest extent of the law, neither the College of Medicine nor the authors, contributors or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the materials herein.