Prevention

Certain herbal medicine products as well as suppléments can reduce the risk of getting a cold. They essentially work by strengthening the body’s immune defenses.

 Vitamin C. At the athletes, vitamin C in supplement form helps prevent colds associated with overtraining syndrome. A meta-analysis shows a 50% decrease in the risk of catching a cold in subjects who took vitamin C for 3 to 8 weeks before a race or a strenuous period of another type of activity¹³.

Dosage

Take 250 mg to 1 g per day, starting about 3 weeks before the period of intense exercise.

 Vitamin C. In the general population, the daily intake of vitamin C supplements would be ineffective to prevent colds, according to a meta-analysis of 30 trials and 11 people¹⁴.

 Ginseng (Panax ginseng). Studies indicate that in conjunction with a influenza vaccine, ginseng reduces the incidence of acute respiratory infections, including the common cold^4,5. At unvaccinated people against the flu, a study published in 2005 found that ginseng would only modestly reduce the number of colds (-13%)⁶.

Dosage

Take 100 mg to 200 mg of a standardized extract (4% to 7% ginsenosides), twice a day. Consult the Ginseng file for more information.

In Canada, the cure COLD-fX®, made from North American ginseng root, is widely used in the prevention of colds. In 2009, a review concluded that although several trials suggest a reduction in the number of colds and the duration of symptoms, the scientific data are not sufficient to certify the preventive effectiveness of COLD-fX®.⁵².

 probiotics. A random study published in 2010 evaluated the effectiveness of a mixture of probiotics (Lactobacillus plantarum (DSM 15312) and Lactobacillus paracasei (DSM 13434)) taken as prevention against colds. In the group receiving probiotic supplements, the risk of catching a cold was 55% versus 67% in the control group, and the duration of colds was reduced by more than 2 days⁵⁴. In 2009, a study carried out on 326 children aged 3 to 5 years showed the preventive effectiveness of the probiotic Lactobacillus acidophilus alone or in combination with Bifidobacterium animalis, administered twice daily for 2 months⁵⁵. Compared with placebo, probiotics reduced the incidence of cancer by more than half. fever and cough, and a 30% incidence of nasal congestion (60% with the combination of the two probiotics).

 Andrographis (Andrographis paniculata). Andrographis may be effective in preventing colds. A placebo-controlled study was carried out on 107 people aged 18, on average⁷. Some of the participants took 2 mg of an extract standardized to 100% of andrographolide twice a day. The subjects taking the andrographis extract were half as likely to contract a cold than those taking the placebo. However, this benefit of andrographis was manifested only after 5,6 months of treatment. No adverse effects have been reported.

 echinacea (Echinacea sp). Echinacea’s effectiveness in preventing colds appears to vary, studies show^{8-11 ,48,49}. It could depend on the type of echinacea preparation used and also on the type of virus that causes the common cold. According to pharmacist Jean-Yves Dionne, echinacea loses its preventive effectiveness after 3 months of use. Read his full review in the Echinacea sheet.

 Glutamine. Taking glutamine before or immediately after strenuous exercise may also help prevent overtraining syndrome, but only one study focused on this use¹⁵.

 Astragalus (Astragalus membraceanus ou Huang qi). The root of this plant is used in Traditional Chinese Medicine to increase the body’s resistance to viral infections. Some studies carried out in China tend to show that astragalus could strengthen the immune system and thus prevent the common cold^12,50. It would also reduce the symptoms of the common cold once it sets in and speed up healing.

Dosage

Consult the Astragalus sheet.

Processing

These products are used for relieve cold symptoms if it is reached and to overcome it more easily.

 Andrographis (Andrographis paniculataIn February 2004, the authors of a review of 4 randomized, double-blind trials concluded that andrographis, alone or in combination with eleutherococcus, is more effective than placebo in treating uncomplicated respiratory infections. (colds, flu, pharyngitis)¹⁶. The authors of a review of studies published 2 months later came to the same conclusion¹⁷.

One study looked at children aged 4 to 11 years old, with positive results⁴¹. No adverse effects have been reported.

Dosage

Take 400 mg of a standardized extract containing 4% to 6% andrographolide (active ingredient in andrographis), 3 times a day.

Contraindication

The pregnant women should refrain from consuming andrographis since it could have abortive effects.

 Zinc. Despite the publication of mixed results over the years^{20-32 ,50}, a summary published in 2013⁶⁴ concluded that zinc, at a high dose of more than 75 mg per day, reduced the duration of the common cold but not its severity. It must be administered within the first 24 hours and very often at this dose causes nausea and a bad taste in the mouth.

Dosage

Consult the Zinc sheet for more information.

 echinacea (Echinacea sp). In 2006⁴⁸ and in 2007⁴⁹, 2 meta-analyzes each grouping about fifteen trials concluded that, despite certain inconclusive results, treatment with echinacea slightly reduced the intensity of cold symptoms (congestion, runny nose, sore throat, sore throat). head, weakness and chills) and reduce their duration by 1,4 days on average. However, a clinical trial whose results were published in December 2010 found no noticeable decrease in symptoms.⁵⁷.

Dosage

If a person still wants to try it, it is important to take Echinacea as soon as possible. first signs of a cold. Some therapists even recommend a loading dose. For all the details, see the Echinacea fact sheet.

 Vitamin C (ascorbic acid). Over the past decades, many studies have looked at the effectiveness of vitamin C in reducing cold symptoms. A meta-analysis⁶⁵ published in 2013 concluded that vitamin C is not effective. Curiously, these authors still say that given the low cost and the absence of toxicity, a person can still give it a try.

 Ail (Allium sativum). ESCOP recognizes the use of garlic to treat respiratory tract infections. The results of a double-blind clinical trial with placebo gave weight to this traditional use: among the 146 subjects treated, those who took a garlic capsule for 12 weeks (between the months of November and February) had fewer colds than those in the placebo group. In addition, when they had a cold, their symptoms resolved more quickly.¹⁹.

Dosage

Garlic can be eaten fresh, dried, or in some other form. Consult the Garlic (psn) and Garlic fact sheets for more information.

 Pepper mint (Mentha x piperita). Commission E and ESCOP recognize the use ofEssential oil peppermint for cough and cold relief, internally or externally.

Dosage

It can be taken internally, or as a nasal ointment. Consult the Peppermint fact sheet.

 Plantain (Plantago major). The German Commission E has approved, since 1985, the medicinal use of lanceolate plantain to treat infections and inflammations of the respiratory tract, internally. In Europe, the plant is an ingredient in several expectorant and cough suppressant herbal preparations.

Dosage

Take as an infusion, tincture or fluid extract. Consult the Plantain fact sheet for more information.

 Licorice (Glycyrrhiza glabra). The root of licorice is one of a multitude of traditional medicinal preparations. Commission E recognizes its use to treat inflammations of the respiratory tract. Certain substances contained in licorice would exert a antiviral effect.

Dosage

It is used internally, as a dried root or as a total extract. See the Liquorice sheet for more information.

 Black elderberry (Sambucus nigra). Commission E approves the use of this plant to treat colds. It would be particularly effective in lowering the fever, according to the British Herbal Compendium. Several trials have shown the effectiveness of elderberries in reducing flu symptoms^50,53, including cough and nasal congestion, which are the main symptoms of the common cold.

Dosage

See details Black elderberry.

Notes. Do not confuse black elderberry (Sambucus nigra) with white elderberry (Sambucus canadensis).

 White willow (Salix alba). Commission E recognizes its use to treat illnesses accompanied by fevers, rheumatism and headaches.

Dosage

See the White willow file.

 Traditionally, several herbs have been used to relieve cold symptoms, such as sore throat and the cough. Among these are isatis, angelica, German chamomile, catnip, eucalyptus, ginger and thyme. Consult our corresponding sheets to find out how to use them.

 Acupuncture. It may help reduce the intensity and duration of symptoms, but no large-scale scientific studies have evaluated its effectiveness.³⁷. See our Acupuncture sheet.

 Food. Certain changes in the diet can help strengthen the immune system, thus speeding up recovery. See the Special Diet: Cold and Flu sheet.

Milk? Based on their clinical experience, some doctors argue that daily consumption of cow’s milk and dairy products opens the door to recurring infections, such as colds, ear infections and sinusitis.^38,39. According to them, milk contributes to the accumulation of toxins in the tissues. Occasional consumption would not be problematic. However, this opinion is not shared by the majority of doctors. In addition, most nutritionists do not recommend dairy products for repeated colds.⁴⁰.

As to D^r Andrew Weil, he recommends including champignons Asians (such as maitake, cordyceps, shiitake and reishi), from the first cold symptoms³⁵. These fungi are said to help strengthen the immune system.

 Chinese Pharmacopoeia. The preparation Yin Qiao San was created to fight infectious diseases in children. It should be taken as soon as the symptoms of a cold appear. The preparation Yu Ping Feng San (Wan) is indicated for people who suffer from recurring colds, for children who go from colds to ear infections or other respiratory infections, and for those who have allergies. A meta-analysis conducted in 2007 analyzed 14 studies involving 2 patients and evaluating different Chinese herbal preparations. Despite the questionable methodology of the studies, the authors concluded that the Chinese pharmacopoeia could reduce the duration of the common cold, without however being able to recommend a particular preparation.⁵⁶.

For other ways to treat colds using Chinese pharmacopoeia, see the article Fighting colds the Chinese way.

 “Grandmother’s remedies”. The following traditional remedies are recommended by Physicians or have some scientific basis³⁶.

• Chicken broth. To help clear the sinuses while promoting antibacterial and antiviral activity, take hot chicken broth seasoned with onion, garlic, cayenne pepper or hot peppers.
• Inhalation d’eucalyptus (Eucalyptus radiata or E. globulus). To relieve, clear and disinfect the respiratory tract, inhale eucalyptus vapors for 15 minutes, 3 times a day in the acute phase, and once before bedtime when the common cold subsides.
• Honey and lemon. The combination of honey and lemon helps to relieve irritation in the throat. Honey could also inhibit the reproduction of bacteria in the throat.
• Herbal tea Ginger (Zingiber officinale). This classic “warming” herbal tea helps relieve cold symptoms. Infuse 1 tbsp. grated fresh ginger in 250 ml of boiling water for 10 minutes.
• Herbal tea cannelle (Cinnamomum zeylanicum). Infuse 1 tbsp. tablespoons of cinnamon powder and 2 cloves of garlic in 250 ml of boiling water for 20 minutes. Flavor with a little honey and lemon. Drink 1 to 3 cups a day.
• Herbal tea melissa (Melissa officinalis). This herbal tea with antiviral properties helps reduce fever associated with colds and flu. Infuse for 10 minutes 1 tsp. tablespoons of dried lemon balm leaves in 250 ml of boiling water.
• Tisane d’red elm (red ulmus). Slippery elm contains mucilage that relieves irritation in the throat. Mix 1 tbsp. powdered slippery elm with 200 ml of water and a little honey. Gargle lightly then swallow in small sips.
• Tisane d’perfumed eupatory (Eupalorium perforliatum) and D’achillée yarrow (Achillia millefolium). Make an herbal tea with ½ tsp. of eupatoire and ½ tsp. teaspoon of yarrow; infuse for 30 minutes in 1 cup (250 ml) of water. The association causes profuse sweating and stimulates the immune system. Drink as hot as possible.
• Total Antilles cocktail. This traditional recipe from the West Indies has been proven for generations: mix 125 ml lemon juice, 2 tbsp. tablespoon vinegar, 1 crushed garlic clove, 1 tbsp. grated fresh ginger and a little cayenne pepper. Swallow all at once.