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The First Thing to Do When a Cold or Flu Strikes

The First Thing to Do When a Cold or Flu Strikes

By Dr. Mercola - New York Times Bestselling Author

During every cold and flu season we can expect lots of advertisements for flu vaccines.
I've written extensively on the dangers of flu vaccines before, and the fact that they simply do not work—according to the scientific evidence.
So here's a timely review of what you can do to protect yourself and your family from colds and any type of flu this season, and in years to come.

What Causes Colds and Influenzas?
Both colds and various influenzas are caused by a wide variety of viruses (not bacteria). While the two ailments typically affect your respiratory tract, there are some differences between them. Common symptoms of a "regular cold" include runny nose, congestion, cough, and sore throat. The symptoms of the flu tend to be far more severe, as the influenza viruses are capable of causing severe lung infection, pneumonia, and even respiratory failure. They also tend to affect your joints—hence that allover achy feeling.
The most common way these viruses are spread is via hand-to-hand contact. For instance, someone with a cold blows their nose then shakes your hand or touches surfaces that you also touch.
However, the key to remember is that just being exposed to a cold virus does not mean that you're destined to catch a cold.
If your immune system is operating at its peak, it should actually be quite easy for you to fend off the virus without ever getting sick. Ditto for flu viruses. If your immune system is impaired, on the other hand, they can easily take hold in your body. So, it's important to understand that the reason you catch a cold or flu is that your immune system is impaired. It's not an inevitable event based on exposure alone.

Lifestyle factors that can depress your immune system, alone or in combination, include:
Eating too much sugar, particularly fructose, and too many grains. The average person is consuming about 75 grams of fructose per day, and when fructose is consumed at that level it can devastate your immune system.
One of the ways it does this is by unbalancing your gut flora. Sugar is "fertilizer" for pathogenic bacteria, yeast, and fungi that can set your immune system up for an assault by a respiratory virus. Most people don't realize that 80 percent of your immune system actually lies in your gastrointestinal tract. That's why controlling your sugar intake is CRUCIAL for optimizing your immune system.
It would be wise to limit your total fructose consumption to below 25 grams a day if you're in good health, or below 15 grams a day if you have high blood pressure, diabetes, heart disease, or are insulin resistant.
Vitamin D deficiency, as a result of insufficient sun exposure. Not getting enough rest
Insufficient exercise. Using ineffective strategies to address emotional stressors
Vitamin D Deficiency: An Underlying Cause of Both Colds and Influenzas
It's estimated that the average U.S. adult typically has two to four colds each year, while children may have up to a dozen. Each year, between five and 20 percent of the US population also come down with flu-like illness, according to Medline.1
One reason for the widespread prevalence of colds and the flu may be that vitamin D deficiency is incredibly common in the United States, especially during the winter months when cold and flu viruses are at their peak. Research has confirmed that "catching" colds and flu may actually be a symptom of an underlying vitamin D deficiency. Less than optimal vitamin D levels will significantly impair your immune response and make you far more susceptible to contracting colds, influenza, and other respiratory infections.
In the largest and most nationally representative study2 of its kind to date, involving about 19,000 Americans, people with the lowest vitamin D levels reported having significantly more recent colds or cases of the flu -- and the risk was even greater for those with chronic respiratory disorders like asthma. At least five additional studies also show an inverse association between lower respiratory tract infections and vitamin D levels.

Read more about this vitamin D study.
But the research is quite clear, the higher your vitamin D level, the lower your risk of contracting colds, flu, and other respiratory tract infections. I strongly believe you could avoid colds and influenza entirely by maintaining your vitamin D level in the optimal range.

IMPORTANT: Why Getting Your Vitamin D from Sun Exposure Is So Important
In a recent interview, Dr. Stephanie Seneff brought the importance of sun exposure to a whole new level. I've consistently recommended getting your vitamin D from regular sun exposure whenever possible, and Dr. Seneff's review of how vitamin D—specifically from sun exposure—is intricately tied to healthy cholesterol and sulfur levels makes this recommendation all the more important. To review the details, please listen to the interview below.
However, as a quick summary, when you expose your skin to sunshine, your skin synthesizes vitamin D3 sulfate. This form of vitamin D is water soluble, unlike oral vitamin D3 supplements, which is unsulfated. The water soluble form can travel freely in your blood stream, whereas the unsulfated form needs LDL (the so-called "bad" cholesterol) as a vehicle of transport. Her suspicion is that the oral non-sulfated form of vitamin D likely will not provide the same benefits as the vitamin D created in your skin from sun exposure, because it cannot be converted to vitamin D sulfate.
I believe this is a very compelling reason to make a concerted effort to seek to get your vitamin D requirements from safe exposure to sunshine, or by using a safe tanning bed (one with electronic ballasts rather than magnetic ballasts, to avoid unnecessary exposure to EMF fields). I have maintained my level between 65 and 110 ng/ml with regular sun exposure.
I recognize that these options may not be feasible for most people, and certainly an oral vitamin D3 supplement will be much than nothing at all.

Vitamin D May Help You Recover Quicker… and Prevent a Cold or Flu in the First Place
Vitamin D is an amazingly effective antimicrobial agent, producing 200 to 300 different antimicrobial peptides in your body that kill bacteria, viruses, and fungi. So optimizing your levels will not only help send a cold or flu virus packing… it will prevent them from invading your body in the first place.
Contrary to flu vaccines (which I'll discuss in a moment), this recommendation has been gaining scientific validation.
For example, in one study, published last year,3 researchers investigated the effect of vitamin D on the incidence of seasonal influenza A in schoolchildren. For over a year, they conducted a study comparing the effects of vitamin D3 with placebos. They found that influenza A occurred in just 10.8 percent of the children in the vitamin D group, compared with 18.6 percent children in the placebo group.

According to the authors:
"This study suggests that vitamin D3 supplementation during the winter may reduce the incidence of influenza A, especially in specific subgroups of schoolchildren."
Based on the latest investigations by Carole Baggerly, director of GrassrootsHealth, the average adult dose required to reach healthy vitamin D levels is 8,000 IU's of vitamin D per day, if you're taking an oral supplement. For children, many experts agree they need about 35 IU's of vitamin D per pound of body weight. However, keep in mind that vitamin D requirements are highly individual, as your vitamin D status is dependent on numerous factors, so while these recommendations may put you closer to the ballpark of what most people likely need, it is impossible to make a blanket recommendation that will cover everyone's needs.
The only way to determine your optimal dose is to get your blood tested. Ideally, you'll want to maintain a vitamin D level of 50-70 ng/ml year-round. For an in-depth explanation of everything you need to know before you get tested, please read my latest updates in "Test Values and Treatment for Vitamin D Deficiency."

Conventional Cold and Flu Strategies May Actually Slow Down Healing
Most uncomplicated colds last between eight and nine days, about 25 percent last two weeks, and 5-10 percent last three weeks. Even the most stubborn colds will typically resolve in a few weeks' time.
Influenzas on the other hand, tend to be shorter in duration, with the typical flu case lasting four to seven days. How quickly you bounce back is often defined by your collective lifestyle habits -- and this does not mean popping over-the-counter cold and flu remedies or fever reducers. In fact, as long as your temperature remains below 102 degrees Fahrenheit (38.9 degrees Celsius) there is no need to lower it.

Cold viruses do not reproduce at higher body temperatures, so a slight fever should actually help you get rid of the virus quicker.

Also avoid over-the-counter pain-relief medications, as research suggests that taking aspirin or Tylenol (acetaminophen) may actually suppress your body's ability to produce antibodies4 to destroy the cold virus. Aspirin has also been linked to lung complications including pulmonary edema, an abnormal buildup of fluid in your lungs, when taken in excess. Only use these medications when absolutely necessary, such as if you have a temperature greater than 105 degrees F (40.5 degrees C), severe muscle aches, or weakness.
Most importantly, remember that antibiotics do NOT work against viruses, hence they are useless against colds and flu. Unfortunately, antibiotics are vastly over-prescribed for this purpose. So please, if you have a cold or flu, remember that unless you have a secondary bacterial pneumonia, an antibiotic will likely do far more harm than good, because whenever you use an antibiotic, you're increasing your susceptibility to developing infections with resistance to that antibiotic -- and you can become the carrier of this resistant bug and can spread it to others.

When Should You Call Your Physician?
Sinus, ear, and lung infections (bronchitis and pneumonia) are examples of bacterial infections that DO respond to antibiotics. If you develop any of the following symptoms, these are signs you may be suffering from a bacterial infection rather than a cold virus, and you should call your physician's office:
Fever over 102 degrees Fahrenheit (38.9 degrees Celsius). Ear pain. Pain around your eyes, especially with a green nasal discharge. Shortness of breath or a persistent uncontrollable cough. Persistently coughing up green and yellow sputum
Shocking LACK of Evidence Supporting Flu Vaccines
While the flu vaccine is touted as the "best" way to avoid catching the seasonal flu, what many fail to realize is that the science available actually does NOT support this conclusion. In essence, it's wishful thinking that is unsupported by scientific evidence.
Take the Cochrane Database Review for example—which is the gold standard for assessing the effectiveness of common medical interventions—as discussed here in a recent article on Here are five Cochrane Database Reviews, published between 2006 and 2010, completely decimating the claim that flu vaccinations are the best course of action to prevent the flu.
A large-scale, systematic review of 51 studies, published in the Cochrane Database of Systematic Reviews6 in 2006, found no evidence that the flu vaccine is any more effective than a placebo in children under two. The studies involved 260,000 children, ages six to 23 months.Two years, later, in 2008, another Cochrane review7 again concluded that "little evidence is available" that the flu vaccine is effective for children under the age of two.
Even more disturbingly, the authors stated that: "It was surprising to find only one study of inactivated vaccine in children under two years, given current recommendations to vaccinate healthy children from six months old in the USA and Canada. If immunization in children is to be recommended as a public health policy, large-scale studies assessing important outcomes and directly comparing vaccine types are urgently required."
Then, last year, Cochrane published the following bombshell conclusion:8
"Influenza vaccines have a modest effect in reducing influenza symptoms and working days lost. There is no evidence that they affect complications, such as pneumonia, or transmission.

WARNING: This review includes 15 out of 36 trials funded by industry (four had no funding declaration). An earlier systematic review of 274 influenza vaccine studies published up to 2007 found industry funded studies were published in more prestigious journals and cited more than other studies independently from methodological quality and size. Studies funded from public sources were significantly less likely to report conclusions favorable to the vaccines.
The review showed that reliable evidence on influenza vaccines is thin but there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies. The content and conclusions of this review should be interpreted in light of this finding." [Emphasis mine.]
Last year, Cochrane also reviewed the available evidence with regards to protecting the elderly,9 and the results were equally abysmal. The authors concluded that: "The available evidence is of poor quality and provides no guidance regarding the safety, efficacy or effectiveness of influenza vaccines for people aged 65 years or older."
They also reviewed whether or not vaccinating health care workers10 can help protect the elderly patients with whom they work. In conclusion, the authors state that: "[T]here is no evidence that vaccinating health care workers prevents influenza in elderly residents in long-term care facilities.

Dietary Strategies to Kick a Cold or Flu
The first thing you want to do when you feel yourself coming down with a cold or flu is to avoid ALL sugars, artificial sweeteners, and processed foods. Sugar is particularly damaging to your immune system -- which needs to be ramped up, not suppressed, in order to combat an emerging infection. This includes fructose from fruit juice, and all types of grains (as they break down as sugar in your body).
Ideally, you must address nutrition, sleep, exercise, and stress issues the moment you first feel yourself getting a bug. This is when immune-enhancing strategies will be most effective. Foods that will help strengthen your immune response include: Raw, grass-fed organic milk, and/or high quality whey protein, fermented foods such as raw kefir, kimchee, miso, pickles, sauerkraut, raw, organic eggs from pastured chickens, grass-fed beef, coconuts and coconut oil, organic vegetables, garlic, ideally consumed raw and crushed just before eating, turmeric, oregano, cinnamon, cloves, mushrooms, especially Reishi, Shiitake, and Maitake.
Make sure to drink plenty of pure water. Water is essential for the optimal function of every system in your body and will help with nose stuffiness and loosening secretions. You should drink enough water so that your urine is a light, pale yellow.

As for chicken soup, yes, it can indeed help reduce cold symptoms.
Chicken contains a natural amino acid called cysteine, which can thin the mucus in your lungs and make it less sticky so you can expel it more easily. Processed, canned soups won't work as well as the homemade version, however. For best results, make up a fresh batch yourself (or ask a friend or family member to do so) and make the soup hot and spicy with plenty of pepper.
The spices will trigger a sudden release of watery fluids in your mouth, throat, and lungs, which will help thin down the respiratory mucus so it's easier to cough up and expel.

Green Tea—A Healthful Beverage Choice During Flu Season
Green tea contains antiviral components that may also be helpful against flu infection. A recent study11 examined the association between green tea consumption and the incidence of influenza among schoolchildren. More than 2,000 elementary school pupils received anonymous questionnaires about their tea consumption and illness during influenza season.
The results showed that drinking green tea, up to five cups per day, was associated with a lower rate of infection.

According to the authors:
"Our findings thus suggest that the consumption of 1-5 cups [per day] of green tea may prevent influenza infection in children."

Supplements That Send Pathogens Packin'
Supplements can be beneficial for colds, but I believe they should be used only as an adjunct to other healthy dietary and lifestyle measures discussed in this article. Some of the more helpful options for cold and flu--above and beyond vitamin D--are:
Vitamin C: A very potent antioxidant; use a natural form such as acerola, which contains associated micronutrients. You can take several grams every hour till you are better unless you start developing loose stools
Oregano Oil: The higher the carvacrol concentration, the more effective it is. Carvacrol is the most active antimicrobial agent in oregano oil.
Propolis: A bee resin and one of the most broad-spectrum antimicrobial compounds in the world, propolis is also the richest source of caffeic acid and apigenin, two very important compounds that aid in immune response.
A tea made from a combination of elderflower, yarrow, boneset, linden, peppermint, and ginger: Drink it hot and often for combating a cold or flu. It causes you to sweat, which is helpful for eradicating a virus from your system.
Olive leaf extract: Ancient Egyptians and Mediterranean cultures used it for a variety of health-promoting uses and it is widely known as a natural, non-toxic immune system builder.

Mushrooms—An Oft-Ignored Immune Booster
There is another exciting emerging supplement that can be a very helpful adjunct to supporting your immune system, and that's mushrooms.
Over 300 different species of mushrooms are now believed to have human health-promoting potential. Evidence continues to emerge, confirming how mushrooms' proteins, trace minerals, polysaccharides, amino acids, and fiber support overall health by:
Promoting normal cellular growth. Protecting against environmental stressors. Supporting your body's normal detoxification process. Supporting healthy gut flora
Promoting optimal digestion. While most people think only of eating the fleshy fruiting body of the mushroom, meaning the part you see growing above ground, most of the magic in the mushroom is actually located in their complex root structure that grows underground, called the mycelium, which can be up to 95 percent of a mushroom's total biomass.
Beta glucans and proteoglycans are the primary biologically active compounds in the mushroom fruit body and mycelia that support your immune system.
Beta glucans are chains of polysaccharides, and proteoglycans are special proteins, often found in connective tissue. The beta glucans found in mushrooms are large and complex long-chain molecules. What sets certain beta glucans apart are their unique side-branching patterns. Just like a key and lock, the beta glucan compounds in mushrooms "fit" perfectly with cellular receptor sites that support your immune system.

At the First Sign of Cold Symptoms: Zinc to the Rescue!
A Cochrane Database Review of the medical research on zinc found that when taken within one day of the first symptoms, zinc can cut down the time you have a cold by about 24 hours.
The review included 15 randomized control trials, consisting of 1360 participants of all age groups. Zinc was also found to greatly reduce the severity of symptoms.
This confirms what many people have long thought about zinc. The review stopped short of recommending any specific dose of zinc, citing the need for further studies to establish optimal formulations and durations of treatment. However, some of the studies reviewed showed the beneficial qualities of zinc in fighting the common cold used between 50 and 65 mg a day.12 The people taking lozenges were more likely to experience adverse effects than those taking syrup, including a bad taste in their mouth and nausea.

Zinc was not recommended for anyone with an underlying health condition, like lowered immune function, asthma, or chronic illness.

Also keep in mind that any time you isolate one mineral and ingest it independently of the others, the potential exists for imbalance, or in the worst case, overdose. Therefore, I wouldn't currently recommend taking more than 50 mg a day, and I wouldn't suggest taking even those supplemental levels on a daily basis to help ward off colds in the first place as you could easily develop a copper imbalance. You can also activate the "Reverse Effect" in which too much of a good nutrient can actually cause the opposite of what it's supposed to do.

Other Lifestyle Strategies that Promote a Cold and Flu-Free Existence
Besides the nutritional interventions already discussed, the following lifestyle strategies will also help optimize your overall resistance against cold and flu viruses:
Get plenty of high-quality sleep. If you aren't getting enough sleep, or enough restorative sleep, you'll be at increased risk for a hostile viral takeover. Your immune system is also the most effective when you're not sleep-deprived, so the more rested you are the quicker you'll recover. For more tips, read my article on 33 secrets for a good night's sleep.
Exercise regularly. Regular exercise is a crucial strategy for increasing your resistance to illness. There is evidence that regular, moderate exercise can reduce your risk for respiratory illness by boosting your immune system. In fact, one study found that people who exercised regularly (five or more days a week) cut their risk of having a cold by close to 50 percent.
And, in the event they did catch a cold, their symptoms were much less severe than among those who did not exercise.
Exercise likely cuts your risk of colds so significantly because it triggers a rise in immune system cells that can attack any potential invaders. Each time you exercise you can benefit from this boost to your immune system. Ideally, establish a regular fitness program, such as Peak Fitness, now to help you ward off colds and other illness.
Furthermore, exercise can also help boost your immune system acutely by increasing your body temperature. This helps kill off invading pathogens, similarly to the fever your body produces when sick.
Address your emotional stress. Emotional stressors can also predispose you to an infection while making cold symptoms worse. Finding ways to manage daily stress as well as your reactions to circumstances beyond your control will contribute to a strong and resilient immune system. Effective strategies include a variety of energy psychology tools, such as the Emotional Freedom Technique (EFT).

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