We all know how the flu — and the common cold — can make life miserable.
Colds afflict many adults one to four times a year and sicken young children more frequently.
And they take a collective toll. Annually, colds cause about 20 million doctor visits, 40 million lost school and work days, and some $25 billion in economic losses.
Flu symptoms — fever, chills, fatigue, headache, sore throat, and muscles/joint aches — typically last three to five days, but you may feel generally crummy for 10 to 14 days.
Cold symptoms usually peak after one to three days and may last seven to 10 days (or longer), and include sore throat, runny nose, sneezing, cough, and fatigue.
To help avoid the flu and colds, wash your hands frequently, avoid crowds in confined places, and don’t get too close to sick people, because a typical sneeze travels from 12 to 32 feet.
Because colds and the flu are viral diseases, antibiotics are useless and should not be used to treat them.
What works for colds and the flu?
There are no vaccines or effective preventive drugs for the common cold.
Flu vaccines range from 20% to 70% effective, depending on the year and the dominant flu strain in circulation.
Standard over-the-counter remedies for cold and flu symptoms can certainly ease suffering — but can produce side effects like drowsiness, and often contain artificial sweeteners, colorings, and other undesirable ingredients.
Many people turn to natural remedies, which is perfectly reasonable, given their general safety and (in some cases) long histories of use.
The challenge is knowing which ones actually help prevent, alleviate, or shorten colds or the flu.
Let’s examine the evidence for some popular and little-known options, starting with cold and flu remedies we categorize as "primary", because they enjoy the best evidence of efficacy and/or the strongest, longest tradition of effective use.
Primary cold remedies: Zinc and vitamin C
These three natural remedies can help prevent a cold, reduce its symptoms, or shorten your period of suffering.
- Zinc. Clinical trials show that — if taken within 24 hours of the onset of symptoms — a daily dose of 75mg to 100mg of zinc or more can shorten a cold’s duration by about one-third in adults — but not in children. Doses higher than 100mg/day do not add any benefits, and lozenges appear to be the most effective form, with zinc acetate and zinc gluconate lozenges performing equally well (Hemilä H et al. 2017).
- Vitamin C. The authors of the most recent evidence review concluded that daily vitamin C supplements don’t prevent colds but can reduce their duration. As they wrote, “it may be worthwhile for cold patients to test … whether therapeutic vitamin C is beneficial for them.” (Hemilä H et al. 2013)
Primary flu remedies: NAI-type drugs or herbs
In addition to these options for influenza, it makes sense to get vaccinated, especially if you're over 60 or suffer from compromised immunity.
Studies suggest that vaccination can reduce your risk of flu substantially, but scientists must try to predict which strains are most likely to hit during a given winter, and they can be wrong.
The only substances proven to actually impair flu viruses are called "neuraminidase inhibitors" or NAIs, which work by blocking the enzyme that viruses use to spread.
During the 2009 H1N1 flu pandemic, early treatment of patients with NAI drugs in several countries reduced the number of serious cases and deaths, and did not cause the virus to develop resistance.
However, the two leading natural-source NAIs — black elderberry and berberine — may be just as effective, should produce fewer side effects, and are readily available online and in natural food stores.
- Black elderberry extract. This herbal remedy contains an NAI compound called cyanidin-3-sambubioside. In clinical trials, black elderberry extracts reduced flu symptoms and duration substantially. The respected Natural Standard Research Collaboration reviewed the evidence and assigned black elderberry extract a grade of B for treatment of the flu (Ulbricht C et al. 2014). The published clinical trials tested an extract called Sambucol, but other black elderberry extracts may be equally effective.
- Berberine. This alkaloid abounds in herbal extracts of barberry, Oregon grape, and goldenseal, all of which have folk histories as anti-flu remedies. In addition to acting as an NAI, berberine may exert other antiviral effects, and reduce the inflammation associated with flu. Based on the limited available lab evidence, berberine may work just as well as black elderberry or synthetic NAIs like Tamiflu, but clinical studies are needed to prove its efficacy.
- NAI-type prescription drugs. The only FDA-approved drugs to treat and prevent influenza A and influenza B are NAIs called Tamiflu, Relenza, Inavir, and Peramivir. The U.S. Centers for Disease Control and Prevention recommends NAIs for people at high risk for complications, the elderly, and people at lower risk — if the drug can be administered within two days of the first symptoms. The most common side effects are nausea and vomiting.
Secondary remedies: Mixed or inconclusive evidence
These seven remedies might help, but the evidence remains inadequate or inconclusive.
Some — probiotics, garlic, vitamin D, and ginseng — provide broader health benefits that might bolster immunity or ease symptoms.
- Andrographis paniculata (Kan Jang). This ancient South Asian and Chinese herbal remedy for infections — known as kalmegh in India's ancient Ayurvedic tradition — has been subjected to several clinical tests against the common cold. Most of the trials were paid for by the manufacturer of a proprietary extract called Kan Jang™, and were conducted in part by scientists in its employ. Nonetheless, based on the available clinical evidence, Andrographis shows promise in preventing, alleviating, and shortening colds.
- Vitamin D. Vitamin D is essential to key immune responses (innate and adaptive), but The evidence that vitamin D wards off viral infections is encouraging but a bit mixed: see Flu and Colds Risk Linked to Vitamin D Lack, Vitamin D Cuts Flu Rate in First Clinical Trial, and Friendly Bugs Cut Colds; Vitamin D Defeated. Experts suggest taking 1,000 to 4,000 IUs daily to ensure adequate seasonal immunity. Ask your doctor to check your vitamin D levels, or order an at-home test from the Vitamin D Council.
- Probiotics. About 70 percent of your immune system resides in your gut, in the form of friendly bacteria, otherwise known as probiotics. The authors of the two most recent evidence reviews concluded — based on research of low to very low quality — that probiotics may reduce the symptoms of colds and other acute upper respiratory tract infections (King S et al. 2014; Hao Q et al. 2015). Cultured foods such as yogurt contain probiotics — mostly Lactobacillus-type bacteria — which are also available in supplement form.
- Oscillococcinum®. This homeopathic remedy is popular for treating the flu, despite a lack of evidence. As the authors of a recent evidence review (Mathie RT et al. 2015) wrote, “There is insufficient good evidence to enable robust conclusions to be made about Oscillococcinum® in the prevention or treatment of influenza and influenza-like illness.” And there's little evidence that over-the-counter, "non-individualized" homeopathic medicines like this one work, although the published trials have been of low quality (Mathie RT et al. 2017). As of this writing, Oscillococcinum® has a 4.5 star rating at Amazon.com, based on 1,145 customer reviews. But the placebo effect is powerful, and the reviewers' decision to purchase signals their belief in its efficacy.
- Echinacea. The most recent evidence review echoed the findings of similar reviews, none of which found any solid evidence that echinacea can prevent colds or reduce their symptoms or duration. Although the authors saw some signs that echinacea might reduce the risk of colds by 10% to 20%, the quality of the evidence was low (Karsch-Völk M et al. 2014).
- Garlic. While the available studies suggest that garlic supplements may cut the frequency of colds, it doesn’t seem to shorten their duration. The most recent evidence review, by Australian researchers, found “insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold.” As the Aussie team wrote, “Claims of effectiveness appear to rely largely on poor-quality evidence.” (Lissiman E et al. 2014) So, garlic may or may not help — we just don’t have enough good evidence to be sure.
- Ginseng. A Canadian team's evidence review found sufficient evidence that ginseng reduces the incidence or severity of common colds, but concluded that it may shorten the duration of colds or flu when taken preventively for two to four months (Seida JK et al. 2011). Ginseng also possesses "adaptogenic" properties that may help you endure the fatigue and discomfort.
- Umcka. The roots of umckaloabo — a South African plant — have long been used in traditional medicine, and extracts were used for tuberculosis in the late 1900's. Today, it's sold as a remedy for upper respiratory infections like bronchitis and the common cold. In some placebo-controlled clinical trials, adults and children with bronchitis who took a specific Umckaloabo extract within two days of feeling sick reported faster recovery. Note: The product tested in most studies — Umcka Cold Care — is (like Oscillococcinum®) a homeopathic preparation that’s been diluted to such an extreme extent that little or no material from the plant remains. As noted above, scientific reviews have found little evidence that over-the-counter, "non-individualized" homeopathic medicines work (Mathie RT et al. 2017). Like Oscillococcinum®, Umcka Cold Care currently holds a 4.5 star rating at Amazon.com, based on many fewer (175) reviews — but our caveat concerning the placebo effect with regard to its purchasers' ratings of Oscillococcinum® would apply here as well.
Supportive diet and lifestyle strategies
It makes sense to adopt five strategies to stay well when everyone around you is calling in sick:
- Dial down inflammation. Inflammation causes many of the symptoms of cold and flu. Eat an anti-inflammatory diet featuring plenty of plant foods, wild-caught fish, herbs, and spices. Supplemental omega-3s, ginger, and curcumin (turmeric extract) can help reduce inflammation. None of these are as potent as non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen. But they don’t cause the adverse, potentially serious gastric side effects associated with NSAIDs.
- Reduce stress. Chronic stress adversely impacts your immune system, and studies show that reducing stress might protect against colds and other respiratory infections. Among anti-stress strategies, regular meditation works well. One trial with adults 50 and older found people in the meditation group had shorter and less severe acute respiratory infections (mostly colds) and lost fewer days of work.
- Get ample sleep. Among its many benefits, sleep helps strengthen your immune system and dampens inflammation. Quality and quantity matter: Aim for eight hours of uninterrupted sleep every night.
- Cut down (or eliminate) sugar. Dietary sugar and refined starch incites inflammation, which impairs immunity and worsens cold and flu symptoms.
- Move consistently. Regular exercise can reduce inflammation, boost immune function, and enhance mood. You were designed to move, and your health depends on it. Find something you love doing, do it frequently, and provide adequate rest and recovery between workouts.
If all else fails to prevent or ease the cold or flu, sip a steaming cup of chicken soup — then curl up with a cup of tea and distract yourself with a hobby, book, or addictive streaming series!
Chicken soup for what ails you
by Kimberly Day
Growing up, there were two things I knew I could count on when I went to grandma’s house.
The first was homemade cookies, and in winter, there'd often be a pot of chicken soup on the stove.
My grandmother swore that chicken soup was the cure for colds and flu. Was she right?
In clinical trials, chicken soup worked better than cold or hot water to foster more mucus flow — a messy but welcome effect when you're stuffed up and can’t sleep.
As well as soothing, hydrating broth, chicken soup is packed with four immune-boosting allies against colds- and flu: onions, garlic, carrots, chicken, and broth.
Onions are rich in quercetin, a flavonoid-family with antioxidant with proven anti-inflammatory and anti-allergenic properties that help inhibit the release of histamine and other pro-inflammatory substances.
One epidemiological study linked higher intake of flavonoids from fruits and vegetables to a lower risk for heart disease, diabetes, and asthma — with the strongest benefits linked to quercetin.
And in test tube and mouse studies, quercetin helped suppress rhinovirus, which causes most common colds.
Quercetin may work because it curbs production of pro-inflammatory compounds, improves lung function, and inhibits growth of rhinovirus in airway cells.
Garlic curbs the growth of bacteria, fungi, and viruses, and its sulfurous allicin compound can stimulate immune functions.
And, like chicken broth, garlic serves as a natural expectorant that stimulates mucus flow.
Carrots are a great source of the vitamin A precursor called beta-carotene, which serves three relevant purposes:
- Supports the structural integrity respiratory tissues.
- Supports formation and maintenance of cell membranes
- Aids the immune system’s ability to protect against pathogens, including cold and flu viruses.
Chicken is a great source of protein, and provides all eight of the amino acids needed to create the antibodies used to attack invaders.
Chicken is also high in selenium, a trace mineral essential to antioxidant enzymes, which also appears to help prevent viruses that have already entered a cell from mutating into more harmful forms.
In short, grandma was right. Chicken soup really is good for what ails. So, in honor of my grandmother and her good, loving advice, here's her recipe.
Grandma’s Chicken Soup
1 tablespoon organic extra virgin olive oil
1 medium onion, chopped
2 medium carrots, chopped
2 medium celery stalks, chopped
1 teaspoon minced garlic
8 cups organic chicken broth
¼ cup fresh parsley
½ teaspoon cayenne pepper
½ teaspoon dried thyme
1 bay leaf
1 cup green beans, cut
½ cup baby spinach
2 small zucchinis, sliced
¾ pound free-range chicken, cooked and cubed
- Sauté onion, carrots, celery, and garlic in olive oil until soft.
- Add chicken broth, parsley, pepper, thyme, and bay leaf. Bring to a boil.
- Reduce heat, cover, and simmer 15-20 minutes.
- Add green beans, spinach, zucchini, and chicken. Cover and simmer 15-20 minutes.
- Remove bay leaf and serve.
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