Eating oranges helps cure a cold

The cold, also called rhinitis or rhinopharyngitis, is a contagious, benign, viral infection that affects the mucous membranes of the nose, sinuses and throat. It is important not to confuse it with the flu (influenza), a more severe infection that affects the entire respiratory system, including the lungs. Many types of viruses can cause the common cold, but over 50% of the cases are caused by the rhinovirus group (1).

The common cold is generally spread through direct hand contact with the nasal secretions of an infected person. More rarely, it can be transmitted by breathing in airborne droplets released when an infected person coughs or sneezes. Colds are particularly contagious in the first few days after symptoms appear (2).

Symptoms of the common cold usually last 5 to 7 days but can sometimes last up to 3  weeks (3):

• Irritation, sore throat or nasal discomfort
• Sneezing and runny nose
• General feeling of unwellness
• Rare, low-grade fever, mainly at the onset of infection

“An untreated cold lasts a week, while a treated cold lasts 7 days!” This old saying clearly points out that most cases of the common cold get better without treatment in less than 10 days. However, treatments may be recommended for some of the more unpleasant symptoms:

• Nasal congestion: use a salt-water spray or nasal rinse, or a decongestant spray for relief.
• Sore throat: take lozenges or syrup to ease irritation.
• Fever, muscle aches and pains: take acetaminophen or ibuprofen to reduce these symptoms.

After the onset of a cold, eating oranges or drinking vitamin C-rich orange juice is no miracle cure. The same is true of a long list of well-known remedies, whether from the natural products industry or from “grandma’s” sage advice:

• Chicken broth
• Garlic and onions
• Ginger and honey
• Eucalyptus and echinacea
• Grapefruit seed extract
• Zinc tablets

Although they can’t cure a cold, some of these products, such as hot chicken broth, herbal tea or a spoonful of honey, can provide temporary relief by helping to ease nasal congestion or a sore throat.

Vitamin C, echinacea and zinc have been the focus of specific studies to assess their usefulness in preventing or treating colds. While some studies have suggested positive effects, these were quickly contradicted by others showing opposing results (3).

Despite the fact that these remedies may or may not be effective against colds, these natural products are generally harmless for your health, as long as you don’t abuse them (4):

Chicken broth – Nothing beats a homemade broth! Commercial broths often contain too much salt, which is not as good for your health.

Garlic – Often recommended for its properties, garlic can leave an unpleasant lingering odour on your breath, as well as in sweat and breast milk. In large quantities, it can cause nausea and irritation of the mouth, esophagus and stomach.

Ginger – Some people report a burning sensation when they consume ginger or a lingering unpleasant aftertaste. Ginger may also slow down digestion and increase the risk of bleeding.

Echinacea – Consuming echinacea can cause side effects such as dizziness, fatigue, headaches and digestive problems. It can also cause allergic reactions, especially in people who are sensitive to certain plants such as ragweed, chrysanthemums or daisies. Be careful if you are predisposed!

Zinc – Beware of high doses – they can be toxic! Zinc lozenges can cause some unpleasant side effects such as:

• Nausea and vomiting
• Diarrhea
• Mouth irritation or sores
• A metallic taste
• Symptoms such as fever, cough or headache and fatigue

Zinc sprays can irritate the nose and throat, and in some cases, cause a loss of smell. It is, therefore, best to avoid them (4,5).

Some natural supplements can interfere with many types of medications:

• Ginger and garlic – medications that prevent the formation of blood clots (anticoagulants).
• Echinacea – (for more than 8 weeks) immunosuppressors used to prevent transplant rejection and drugs that can cause liver damage.
• Zinc – Certain antibiotics used to treat infections can be less effective when taken at the same time as zinc supplements. Zinc should, therefore, be taken 2 hours before or 4 to 6 hours after these antibiotics.
• Grapefruit seed extracts – Grapefruit juice (and juice from some other citrus fruits) is already well known for interfering with medications either by accelerating their metabolism (loss of efficacy), or by decreasing their elimination thus increasing their toxicity. This is the case, for example, with certain drugs used to lower cholesterol, treat high blood pressure or arrhythmia, or those that affect the immune system. Grapefruit seed extract may share some of these interactions.

The list of natural products, their side effects and drug interactions is long and complex. If you are unsure, your pharmacist or another healthcare professional can best advise you.

There are vaccines available for the flu, different strains of COVID-19, respiratory syncytial virus (RSV) and pneumococcal pneumonia. These four vaccines are included in the vaccination programs offered by the Quebec Ministry of Health and Social Services. However, there is no vaccine for colds caused by rhinoviruses.

On the one hand, the wide variety of viruses responsible for the common cold (over 100) and their ability to mutate quickly make it extremely difficult to develop a vaccine. On the other hand, the common cold is a benign infection which, unlike the flu, COVID-19 or RSV, does not result in death or serious disabilities. Therefore, the costs it incurs for the healthcare system are not significant enough to justify a costly immunization program.

Since there are no medications or natural products that can effectively prevent or cure the common cold, and no specific vaccine against rhinoviruses, the best way to protect yourself from the common cold is to adopt simple preventive measures. These measures, well ingrained in our routines since the COVID-19 pandemic, are easy to apply on a daily basis:

• Wash your hands frequently with soap and water or use an alcohol-based antiseptic product (disinfectant), especially if you share a home or workplace with infected people.
• Regularly clean and disinfect frequently touched surfaces, such as counters, door knobs or tables.
• Minimize any contact with people who have a cold and wear a mask to limit the spread of the virus during the contagious period.
• Cover your mouth and nose with a disposable tissue when coughing or sneezing or cough into your elbow or upper arm.

Oranges and other citrus fruits are rich in vitamin C, which is excellent. However, they cannot prevent or cure a cold. That said, including these and other fruits and vegetables in your diet is still a healthy practice. What’s most important is to eat a varied, balanced diet.

This revised edition reflects an updated version from the original version published on our website. We have incorporated recent facts to offer you current and pertinent information.