Preventing Colds and Flu Naturally

Certain vitamins, herbs, and minerals have immune stimulating and anti-viral effects. Population studies show that most people are deficient in particular vital nutrients required to stave off viral respiratory illnesses, such as colds, flu, pharyngitis, laryngitis, and even pneumonia. These deficiencies are generally more severe in the winter months due to a lowered exposure to sunlight, as well as other factors which may include lower mood and activity levels and perhaps less consumption of fresh foods. Some simple things everyone can accomplish to keep the immune system strong this time of year are as follows:

Daily Supplements for a Healthy Immune System


Vitamin D3: Vitamin D deficiency may be the greatest cause of seasonal colds and flu. During the colder seasons and at higher latitudes our bodies produce much less Vitamin D because of lowered skin exposure to direct sunlight. A large study involving 19,000 Americans showed that those individuals with the lowest Vitamin D levels reported having significantly more colds and flu. The risk was even greater in those with chronic respiratory disorders such as Asthma. It is now known that adults can safely consume 5000 IU daily from September through May. (Arch Intern Med. 2009 Feb 23;169(4):384-90. Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey)

Vitamin C: Vitamin C is a potent anti-viral, anti-bacterial, and anti-parasitic agent. Oral vitamin C helps protect the body from developing infections, and high-dose intravenous vitamin C is an effective method of destroying and removing pathogenic microbes. Intravenous vitamin C has cured viral infections which can be debilitating and even life threatening such as swine flu, measles, mumps, viral encephalitis, chicken pox, shingles, herpes, viral pneumonia, colds, and flu. Orally take 1000mg daily. Citrus or berry bioflavonoid compounds have added benefit towards immune stimulation and symptom prevention.

Zinc: Taking supplemental Zinc at the first signs of a cold or flu can cut down the time of the illness significantly as well as reduce the severity of symptoms. Take 75 mg daily in a lozenge form once symptoms have started, or 30mg daily preventively. (Cochrane database review of 15 randomized control trials with 1360 participants.

Vitamin A: This vitamin also shows promise as an anti-viral agent. It inactivates viruses, stimulates the immune system, and protects the mucus membranes of the respiratory track from viral invasion. 10,000 IU daily is safe and effective. Single treatments with much higher doses (100,000-200,000 IU) have shown benefit in treating upper respiratory viral illnesses and childhood viral illnesses such as Chicken Pox and Measles.

Selenium: This mineral is deficient in processed foods and has become increasingly deficient in soils that grow our food. Selenium plays a role in immune function and improves liver function. Taking 200 mcg daily seems prudent.

Probiotics (and avoiding excessive use of antibiotics): Ensuring a healthy population of intestinal bacteria is one of the best ways to keep the immune system strong and functional. 80% of our immune function stems from these healthy bacteria. I often observe less inflammation and infection in people with healthy bowel flora. Antibiotics can destroy the healthy balance of microbes and it is therefore recommended that with any course of antibiotics, probiotics be administered concurrently and for several weeks afterwards.

The following herbs all help to prevent and treat colds and flu:


Garlic, Echinacea, Astragalus, Elderberry syrup, and Oregano Oil. These can be taken as directed.

Also, a homeopathic remedy called Oscillococcinum works wonders when used at the onset of a cold or flu. It can stop the development of these illnesses if taken near the beginning. It comes in little sugar granules which dissolve easily under the tongue (great for children).

And last but not least, the food we eat contributes greatly to immunity. The most significant dietary contributor to seasonal viral infections is sugar. By reducing sugar (and grain carbohydrates that convert to sugar in the body), the immune system remains robust and highly functioning. Studies clearly show that refined sugar lowers levels of immune cells in the blood stream. And of course, as always, ramp up your consumption of fresh, raw or lightly cooked vegetables, healthy oils, and lean protein.

Unfortunately, often prevention is left up to the Flu vaccine alone. But to rely on this method is unwise considering the latest evidence for its relative lack of effectiveness. A review of the science states the following:
“The preventive effect of parenteral inactivated influenza vaccine on healthy adults is small: at least 40 people would need vaccination to avoid one ILI (Influenza-like-illness) case (95% confidence interval (CI) 26 to 128) and 71 people would need vaccination to prevent one case of influenza (95% CI 64 to 80). Vaccination shows no appreciable effect on working days lost or hospitalization.”

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