Colds, Flu and Immunity: Conventional vs Natural Health

  • Nature's Source

We are constantly surrounded by opportunistic would-be pathogens – fungal, bacterial and viral. Yet, most people, most of the time are not adversely affected by them. We fend off, neutralize or mitigate them thanks to what is referred to as an innate ‘immune system’. When a person expresses the constellation of symptoms commonly associated with a ‘cold’ or ‘flu’ it appears that a weakened immune system has allowed an aggressive pathogen – a hostile invader – to proliferate and compromise their health with characteristic results.

Conventional medicine and natural health view and treat cold and flu symptoms in entirely different ways. The conventional approach is to reduce the cold/flu experience to the invasive presence of a specific pathogen against which a synthetic drug or vaccine is prescribed. Regular physicians employ a ‘whack-a-mole’ strategy. If an apparent cold/flu pathogen pops up - suppress it with a drug. They don’t care or even think about the state of person’s immune system.      

The natural health approach is to use specific nutrients – foods and natural health products – to supply the immune system with the ‘raw material’ to restore one a state of normal good health as exists most of the time. Changes in lifestyle, diet, supplements and application of restorative therapies such as acupuncture, chiropractic or exercise are the tools that natural health employs to strengthen your immune system.


Key Foods and Supplements that Strengthen Immunity

There is one critical difference between conventional medicine and natural health as regards immunity. For regular doctors, everybody is the same. You got symptoms? Take this drug, get a flu shot. One size fits all. Doesn’t work? See a specialist. Next patient please.

Natural health understands that people are not all the same. For example, constitutionally some people thrive on a vegetarian diet but others require meat to thrive. Acid/alkaline, sympathetic/parasympathetic, yin/yang, fast oxidizer/slow oxidizer. There is no universal prescription rather there is an algebra that best suits each individual.

You go to a regular doctor; you don’t have to think. You just do whatever they say. With natural health you have to think, observe, learn, evaluate – take responsibility. You are constantly conducting your own clinical trial in which you are both subject and object. It takes work and you must have a critical disposition. The rewards are success, enjoyment of life and control pf your health. You own your own body. Take responsibility.

What follows are state-of-the-art summaries of key nutrients, foods and natural health products that have wide application to enhancing immunity with respect to cold and flu symptoms. Don’t take this advice or consume anything blindly. Read up and ask questions.


At Nature’s Source our rule is: bring us your hardest questions.


Vitamin D

Vitamin D is naturally synthesized by exposure of the skin to sunlight. In northern temperate climates like ours this isn’t happening very much so the level Vitamin D levels is often inadequate. To restore this, supplements are required of which there are two forms: D3, also known as cholecalciferol, and D2, also known as ergocalciferol. The former, produced in the skin on exposure to UVB radiation (290 to 320 nm), is more bioactive. Both D3 and D2 precursors are converted in the liver and kidneys to storage and biologically active forms.

  • In the largest and most nationally representative study of the association between vitamin D and respiratory infections, people with the lowest blood vitamin D levels reported having significantly more recent colds or cases of the flu. The risks were even higher for those with chronic respiratory disorders, such as asthma and emphysema. The report appears in the February 23 2009 Archives of Internal Medicine.
  • High levels of vitamin D may prevent or lower the risk of influenza. Vitamin D may also reduce symptoms of influenza and reduce the risk of developing pneumonia following influenza. William B. Grant, Ph.D. - Vitamin D Council

Vitamin D is not a drug. It is a nutrient. The use of supplementary Vitamin D is to restore or make like normal the blood levels of this vitamin to enhance competence of the immune system. If you are in doubt, a health practitioner can order a simple blood test to determine your level of Vitamin D. 

Oregon State University's Linus Pauling Institute general recommendations for vitamin D are 2,000 IU daily for healthy adults and 600 IU a day for children. The Vitamin D Council recommends on average, 2000-5000 IU/day vitamin D3 may provide protection against influenza.


Vitamin D products:

  • Ddrops Liquid vitamin D3, 1000 IU per drop
  • AOR Vitamin D3 1000 IU capsules
  • Vitamin Code RAW D3 1000 IU capsules
  • SISU Vitamin D 1000 IU tablets
  • Genestra D3 1000 Drops 30 ml liquid



Garlic is an amazing herb that provides a very wide range of benefits. It is generally most potent when consumed raw. Consider this from WebMD:

“Like a number of other supplements, garlic seems to stimulate the immune system. Garlic may also help fight viruses. Also, there is some preliminary evidence that garlic may lower the risk of catching a cold. Garlic works best when consumed raw, either crushed, diced, or minced. Overcooking garlic may destroy important medicinal compounds and the enzymes necessary for it to be effective”. Reviewed by David Kiefer, M.D. on December 29, 2010

How on earth do you actually eat raw garlic? Here’s the trick. When you have prepared a regular-sized meal, beforehand crush a clove of garlic into the well of a spoon, tamp it down and cover in olive oil. Now eat half your meal so there is food in your stomach. At this point simply tip the oil and garlic mix into your mouth and swallow. Don’t chew it; just let it slide down your throat thanks to the oil. Finish your food. That raw garlic will disperse as the food proceeds through your digestive tract which is most effective. This minimizes or completely eliminates any garlic odour which otherwise might express through the lungs or skin. This is a very effective protocol.

There is one supplementary garlic product that has proven effective against colds and flu. This is Allimax. Consider this from the BBC (Wednesday, 3 October, 2001) regarding a study conducted by Peter Josling, director the Garlic Centre in East Sussex.:

People who take a garlic supplement each day are far less likely to fall victim to the common cold than those who do not, research suggests. Although garlic has been traditionally used to fight off and treat the symptoms of the common cold, this is the first hard evidence of its medicinal properties.

The study found that a daily garlic supplement containing allicin, a purified component of garlic considered to be the major biologically active agent produced by the plant, reduced the risk of catching a cold by more than half.

Professor Ron Eccles, director of the Common Cold Centre at Cardiff University, believes this is a very encouraging result. He said: ""I am not going to say this will revolutionize treatment for the common cold but it is very interesting. Plants do not have an immune system like we do - they fight viruses and infections with in-built chemical defenses. So, if you like, allicin is one of the chemical defenses of garlic which helps keep it healthy”.

  • Allimax Cold 30 capsules, 180 mg


Readers will likely know that Echinacea has been both touted and condemned for use regarding cold and flu symptoms, depending on who you listen too. Let’s sort through this.

Pro: The authoritative German Commission E (a governing agency for herbal medicine made up of a committee of physicians, pharmacists, scientists, and herbalists that evaluates the safety, quality, and efficacy of herbs) states Echinacea root and juice extracts are indicated for the supportive treatment of flu-like illnesses and upper respiratory infections.

Con: This is an oft cited study:There were no statistically significant effects of the three Echinacea extracts on rates of infection or severity of symptoms… The results of this study indicate that extracts of E. angustifolia root, either alone or in combination, do not have clinically significant effects on infection with a rhinovirus or on the clinical illness that results from it”. An Evaluation of Echinacea angustifolia in Experimental Rhinovirus Infections, Ronald B. Turner, M.D.,et al,  The New England Journal of Medicine, July 28, 200 vol. 353 no. 4

Anti-Con: This from a conference of the British Royal Society of Medicine “Echinacea in today’s world”, London, September 2012. The conference featured The Cardiff Study led by Professor Ronald Eccles at Cardiff University’s School of Biosciences, which showed the exact opposite of Dr Turner’s earlier research (above). Dr. Eccles and his colleagues found Echinacea to be effective both in preventing and treating colds and flu. The study also found none of serious safety concerns previously reported by Dr Turner’s and other studies, among them the induction of allergic reactions and even autoimmune diseases.

What’s the Balance of Evidence?

  1. Critics of Echinacea for colds and flu have repeatedly used the wrong echinacea species of plant parts in their studies.
  2. Critics have also used sub-therapeutic dosages of Echinacea. For example, Dr. Turner’s study used 900 mg/day while the Canadian Natural Health Products Directorate recommends the equivalent of 3 grams per day.
  3. The strongest evidence suggests that Echinacea is most appropriate to administer at the onset of and during a cold or flu. There is much less evidence that using Echinacea when you are healthy is worthwhile.

The following are good-quality Echinacea products that Nature’s Source has in stock:

  • Vogel Echinaforce 50 ml tincture
  • MediHerb Echinacea Premium 60 tablets
  • Francis Echinacea 50 ml tincture
  • Salus Echinacea 200 ml pure plant juice
  • Natural Factors Anti-Cold 90 capsules, fresh plant extract

Vitamin C

The popular use of Vitamin C for colds began with the publication by Dr. Linus Pauling’s “Vitamin C and the Common Cold” in 1970. Pauling, winner of two Nobel Awards, was a strong advocate of the use of Vitamin C. However, since Vitamin C is cheap and can’t be patented the drug industry quickly sought to discredit its use and still does.

In 1975, the U.S. National Institutes of Health published the ‘Karlowski’ study which held that Vitamin C was worthless. This study has been routinely cited since. In the meantime, an ongoing battle has been waged by advocates an critic of the use of Vitamin C to prevent and treat colds.

What’s the Balance of the Evidence?

  1. In 1995, ascorbic acid authority Harri Hemila, MD, a researcher who works at the Department of Public Health at the University of Helsinki in Finland, took a hard look at the Karlowski study and found that its numbers did not add up. In a review, Hemila found that the researchers had dismissed the possible efficacy of vitamin C too readily, and concluded that, to the contrary, the majority of evidence points to a moderate but significant benefit to taking vitamin C for colds.
  2. In a January 2013 review by the renowned Cochrane Foundation, it was found that Vitamin C was effective against the common cold particularly for people under stress. The review found that regular doses of vitamin C of one gram per day or higher reduced the average duration of colds in adults by 8% and in children by 18%. Given the consistent effect of vitamin C on the duration and severity of colds, and the safety and low cost of vitamin C, the authors considered that it would be worthwhile for common cold patients.

Here are the recommendations of the Linus Pauling Institute at Oregon State University:

Age Group

UL (mg/day)

Children 1-3 years


Children 4-8 years


Children 9-13 years 


Adolescents 14-18 years


Adults 19 years and older


The following are good quality Vitamin C natural health products that Nature’s source carries:

  • AOR Vitamin C 1000 mg, 300 capsules
  • Advantage Health Matters Camu C 500 mg 90 capsules
  • SISU Ester C Supreme 600 mg, 120 capsules
  • Progressive Vitamin C Complex 600 mg, 60 capsules
  • Natural Factors Vitamin C 1000 mg, 90 capsules


The mineral zinc has been widely used as help the body defend against respiratory colds. Usually, zinc gluconate zinc citrate is used often in the form of a throat lozenge. Zinc products are often combined with some Vitamin C.

A Cochrane Review study published June 18, 2013 put the Balance of Evidence rather well:

“Zinc inhibits replication of the virus and has been tested in trials for treatment of the common cold. This review identified 18 randomized controlled trials, enrolling 1781 participants of all age groups, comparing zinc with placebo (no zinc). We found that zinc (lozenges or syrup) reduces the average duration of the common cold in healthy people, when taken within 24 hours of onset of symptoms. In people taking zinc their cold symptoms are also less likely to persist beyond seven days of treatment”.

“As the zinc lozenges formulation has been widely studied, and there is a significant reduction in the duration of cold at a dose of ≥ 75 mg/day, for those considering using zinc it would be best to use it at this dose throughout the cold”.

Here are some excellent zinc and zinc/Vitamin C lozenge products you will find at Nature’s Source:

  • Natural Factors Sore Throat Relief 60 lozenges, zinc/vitamin C
  • New Chapter Zinc Food Complex 60 tablets, food-state form
  • Trophic Chelazome Zinc 60 capsules, chelated zinc
  • Metagenics Zinc Drink 140 ml zinc sulfate

The Flu Shot: Does it actually do any good?

  • Thomas Jefferson, coordinator for the Cochrane Vaccine Field, has stated on the record that in 2009 he conducted a thorough review of 217 published studies on flu vaccines and found only 5% reliable. Dr. Jefferson told Reuters,

 “Immunization of very young children is not lent support by our findings. We recorded no convincing evidence that vaccines can reduce mortality, [hospital] admissions, serious complications and community transmission of influenza. In young children below the age of 2, we could find no evidence that the vaccine was different from a placebo.”

  • Anthony Morris, a distinguished virologist and a former Chief Vaccine Office at the FDA, found:

 “There is no evidence that any influenza vaccine thus far developed is effective in preventing or mitigating any attack of influenza.’ Dr. Morris further states, “The producers of these vaccines know they are worthless, but they go on selling them anyway.”

  • Peter Doshi, of Johns Hopkins University School of Medicine is author of “Influenza: marketing vaccines by marketing disease”; British Medical Journal: 2013; 346:f3037). He states:

“…few people realize that even the ideal influenza vaccine, matched perfectly to circulating strains of wild influenza and capable of stopping all influenza viruses, can only deal with a small part of the ‘flu’ problem…Every year, hundreds of thousands of respiratory specimens are tested across the US. Of those tested, on average 16% are found to be influenza positive….It’s no wonder so many people feel that ‘flu shots’ don’t work: for most flus, they can’t.”

Television Host Piers Morgan went on the Dr. Oz television show to get injected with the toxic flu vaccine in front of a live audience. Days later he came down with the flu.