Winter weather is upon us and for Canadians that means cold season. The majority of colds are caused by viruses, usually the rhinoviruses, and the average adult will suffer through 2-4 colds a year (1). The seemingly unavoidable onslaught of coughing, sniffling, sneezing, and achiness of the common cold means we are looking for anything that will end our misery.
There are a variety of drugs on the market to help reduce the symptoms of a cold but what are the alternatives for those who would prefer natural treatments? Are there complementary and alternative medicines that can reduce the chance of catching a cold or help you recover more quickly?
Echinacea is purported to rev up your immune system. Laboratory studies confirm that Echinacea can activate cells with immune functions and help with antibody response (2,3). All of this is very promising from a theoretical stand point but how effective is Echinacea in real life? It may depend on the type of Echinacea and the part of the plant being used.
There are a variety of different species and a recent systematic review found that Echinacea purpurea was the most effective species and that the beneficial effects were associated with the aerial parts rather than the roots (4). Six studies looking at 764 adults with cold symptoms (but who were otherwise healthy) found the severity of the symptoms was reduced in four of the trials and the symptom duration was shorter in three out of four trials. Conversely, neither of the two studies used to determine if Echinacea could prevent colds found any benefit (5).
Generally, Echinacea is thought to be safe for healthy adults to consume (safety has not been established during pregnancy) with minor side-effects including gastrointestinal upset, headaches and rashes (3, 6). With respect to dosages, 2000 – 3000 mg of extract, 6-9 ml of pressed juice or 0.75 – 1.5 ml of tincture per day is usually recommended (5). A cautionary note, Echinacea can cause severe allergic reactions in some people!
Ginseng has similar effects on the immune system to Echinacea by activating the macrophages, natural killer cells and increased antibodies in animal studies (6,7). The two types of ginseng commonly used are Panax ginseng (Asian ginseng) and Panax quinqufolius (North American ginseng) – similar to that used in COLD-fx. The effectiveness of ginseng on the common cold is difficult to determine at present.
According to a recent review (5) there are no trials looking at the usefulness of ginseng in treating colds among healthy individuals. With respect to prevention, the same authors found three trials, all of which were funded by the manufacturer, and none of which used healthy adults but rather higher risk groups such as the elderly or those in nursing homes (5).
With that in mind, one study did find the elderly patients reported fewer days of cold symptoms (8). In the healthy adults who were at risk for colds they found milder symptoms and fewer days of illness with COLD-fx (9). With respect to Panax ginseng, a study in 227 healthy adults taking 100 mg of the extract had fewer colds than the placebo group (10). If you chose to take ginseng to treat colds potential side-effects include gastrointestinal upset, anxiety and insomnia (5,10). Furthermore, it should not be taken by pregnant or breastfeeding women (11) or those on phenelzine and warfarin. It may also interact with alcohol (12).
Allicin is a compound released from garlic when it is chopped or chewed. Notably, it is inactivated by cooking so it will have to be raw garlic for any potential benefits. Studies to determine if allicin can treat the common cold are lacking; however, there is one study to determine if allicin can prevent colds. Here they used 146 volunteers and gave them 180 mg of allicin extract for 12 weeks during the winter. The allicin group had 64% fewer colds and the duration of their symptoms was decreased by 70%. Furthermore, only 2 of the participants in the allicin group caught more than one cold as compared to 16 people in the placebo group (5,13).
Unfortunately, a typical garlic clove contains 5-9 mg of allicin, which is a much lower dose than the 180 mg of allicin extract used in the study. The safety of allicin, it is still relatively unstudied but “malodorous belching” was reported (5).
Probiotics are bacteria with proposed health benefits. They are more commonly considered as treatments for gastrointestinal diseases; however, they may have other roles in health. Of six studies involving 1766 healthy adults, only one found a reduction in the number of colds, and one had a reduction in the severity of symptoms and duration of the cold (5).
Where probiotics may have benefit, is in those who have been prescribed antibiotics. Typically, antibiotics are not effective against the common cold but if they have been prescribed, probiotics are often an effective adjunct therapy.
No Baloney’s advice? There is limited evidence for the use of these natural health products in the prevention and treatment of the common cold; however, there are also very few effective “standard” treatments. It may come down to trial and error as well as the placebo effect (you convince yourself you feel better just because you took something).
In addition to the therapies mentioned here, vitamin C and zinc lozenges may be beneficial (5) BUT be sure to stay within the recommended safe dosages listed. In all cases, be on the lookout for side-effects and check to make sure that there are no known interactions between the natural health product and any other medications you may be taking. Be extra cautious during pregnancy and if you have other illnesses.
If all else fails you may just have to rest up and let your immune system fight the good fight!