No Time For the Flu? These Five Super Nutrients Offer Potent Protection

Last winter there were 80,000 deaths from the flu—it was our deadliest season in forty years, according to the CDC. A total of 900,000 people were hospitalized for flu or flu-like illness, and that number doesn’t begin to tally the legions of us who coughed, hacked, shivered, and miserably staggered our way through viral illnesses that kept us home from work for days. We need protection from all those pesky, nasty viruses that lay us low: rhinovirus, coronavirus, adenovirus, influenza and parainfluenza virus, respiratory syncytial virus, influenza A virus, Coxsackie virus and more.

Flu and cold season tends to begin in December and peak in February or March. Flu is most common in winter because the virus thrives in cold, dry weather, according to Harvard University. This year, flu activity is once again elevated, and you can check the national percentage of influenza-like illnesses as well as state outbreaks in the CDC’s weekly surveillance report here. The common cold alone leads to 75-100 million doctor visits a year, costing America $7.7 billion annually, with nearly $3 billion of that for over-the-counter medicines.[1]

Though handwashing can reduce transmission of flus and colds up to 30%, and facemasks up to another 10%[2], the most effective protection is a strong, well-functioning immune system. Here are five supernutrients that, in liposomal form for rapid action, can together offer truly protective armor to keep you healthy all winter long.

Vitamin C: Not to Be Overlooked, Ever

It’s well known that supplementation with vitamin C can shorten the duration and severity of colds, and reduce the risk of developing a cold in high-performance athletes.[3],[4] A meta-analysis of eight different studies on Vitamin C showed that therapeutic doses (3-4 grams a day) of the vitamin taken at the onset of a cold could reduce its duration, and reduce fever, chills and chest pain. Vitamin C can enhance the function of our immune system’s potent natural killer cells as well as support white blood cells’ migration to the site of infections and their ability to generate free radicals that can kill microbes.[5] It is naturally concentrated in leukocytes—white blood cells that fight infection and foreign substances—at levels 50- to 100-fold higher than in the blood[6], but the concentration rapidly declines during infections and stress. When healthy volunteers supplemented with vitamin C, their neutrophils—a white blood cell—had enhanced activity.[7]

Because Vitamin C supports collagen, which is a critical building block for skin, ligaments, tendons, teeth and tissues throughout the body, it can help protect tissue during infection. Impaired function in the lining of the lungs of animals with serious infection was restored by supplementing with vitamin C.[8]

One of the most significant ways Vitamin C helps protect us from colds and flus is through its powerful antioxidant impact. Vitamin C can protect the body from damage generated during infections and from exposure to toxins and pollutants. It helps support the body’s energy powerhouses, the mitochondria, by assisting in the synthesis of carnitine.[9]  It can regenerate two critical antioxidants—glutathione and vitamin E.[10]

Vitamin C’s Predictive Power in The “Morbidity” Index

As stated, vitamin C in its antioxidant or “reduced” form can protect cells from free radicals generated when they are fighting infection. Vitamin C’s power is such that levels of the nutrient can actually be used as a predictor of survival. While fighting infection, the antioxidant form of Vitamin C plummets, and the oxidized form surges. Recovery from an infection is marked by a clear shift back to the antioxidant form. This is a profoundly powerful indicator of health and resilience, and gives insight into just how important antioxidant defense is during colds, flus and other infections. Free radicals, when consistently high, can damage cell membranes, enzymes, receptors, and proteins.  In fact, the ratio of antioxidant to oxidized Vitamin C can actually predict morbidity and mortality in severely ill patients—as well as predict who will recover. This is literally called the morbidity index.[11]

Studies have shown that healthy individuals are walking around with a morbidity index of about 14—about 95% of the vitamin C in their bodies is in the antioxidant, reduced form. In contrast, those who were critically ill but survived, had a morbidity index of about 1, while those who died had a paltry 0.3 to 0.5 index.[12] No wonder, then, that Vitamin C in high doses given intravenously, along with thiamine and cortisone, has been shown to help reverse and effectively treat deadly sepsis—a potentially fatal immune response to a serious infection.[13]

Lipoic Acid: A Versatile Antioxidant That Supports Vitamin C

Lipoic acid is an impressively versatile antioxidant that has been studied for everything from neurodegenerative illnesses to insulin resistance and heavy metal toxicity.[14] It’s a naturally occurring organosulfur compound that is synthesized by both plants and animals.[15] It’s an essential cofactor for the mitochondria and the body’s production of energy.[16] Feeding mitochondria is essential when fighting any infection or illness, and decreased mitochondrial energy (through production of ATP) is common during serious illness.[17]

Vitamin C’s antioxidant power is increased by R-Lipoic acid.[18] Both Vitamin C and R-Lipoic acid also upregulate glutathione production within the cell.  Glutathione’s impact on healthy skin is also well known—and we’ll be looking at its impact on immune function in a moment.

Lipoic acid actually has the ability to cross the blood-brain barrier as well.[19] For its support of Vitamin C, Vitamin E and glutathione, it has been called the “universal antioxidant”—and one you want in your arsenal when fighting colds and flu.[20]

Glutathione: The Great Detoxifier and Immune Regulator

Glutathione has been called the ‘mother’ of all antioxidants—and there are over 142,000 peer reviewed studies published to prove it. It’s our built-in natural detoxification system, and it works at the cellular level. It’s a critical step in detoxification system, binding and ‘sticking’ to toxins and free radicals of all kinds, so that your body can safely carry them into your bladder and gut and out of your body.

But what is less well known about glutathione is how profoundly it supports the immune system.  When intracellular glutathione level dips, white blood cells called lymphocytes are impaired and viral infections can percolate. The synthesis of new DNA and new cells is exquisitely sensitive to free radical damage, and high levels of glutathione protect it.[21] And rapid decreases in glutathione levels have been seen after infection with viruses.[22]

Optimal levels of glutathione support a balanced immune response. When intracellular glutathione stores are rich, immune molecules are stimulated, and both viruses and bacteria are inhibited. When reserves of glutathione are low, the immune system switches away from a “Th1” innate immunity response toward a stronger “Th2” inflammatory response, which is dominant in autoimmune diseases, allergic reactions and viral infections like flu and cold. Glutathione has been proven to help improve the balance between Th1 and Th2, and to improve immune response to bacterial infections and even eliminate the bacteria.22

Though oral glutathione is not reliable as a supplement, because stomach acid can easily degrade it, liposomal glutathione has been shown to markedly increase glutathione stores. In one month-long study glutathione went up 40% in whole blood and 100% in the immune system’s critical T cells, B cells, and natural killer cells. Immune function markers were also enhanced—and amazingly, natural killer cells cytotoxicity, or ability to kill, was elevated by up to 400% with liposomal glutathione.[23]

Cat’s Claw: The Ultimate Herbal Defense

The ever-popular botanical Cat’s claw (Uña de Gato) is a Peruvian “cure-all” used for over 2000 years. It is one of the most widely studied rainforest herbs. The natural medicine derived from its inner bark is considered sacred by the Asháninka tribe of Peru, whose healer-priests use it exclusively.[24] Cat’s claw offers an impressive array of healing molecules that are anti-inflammatory and anti-viral, including alkaloids, quinovic acid glycosides, tannins, flavonoids, sterol fractions and more.[25]

Cat’s claw offers powerful immune support and boosts activity of immune cells such as B- and T-lymphocytes.[26] It stimulates the ability of white blood cells to gobble up invaders (known as phagocytosis), and enhances cytokines that enhance immune function.[27] It has been shown to strongly stimulate immune cells called macrophages.[28] In a study of adult males, those who supplemented with cat’s claw for six months saw a boost in their white blood cell count.[29]

Finally, cat’s claw is a potent anti-inflammatory, which can help relieve unpleasant symptoms during viral infection. It has been shown to inhibit pro-inflammatory cytokines, including the potent NF-KappaB and TNF (tumor necrosis factor).[30]

The Beauty of Vitamin D: A Universal Immune Booster

About six years ago science discovered something remarkable: the human genome has thousands of binding sites for vitamin D. It is that critical to life.[31]

Healthy levels of vitamin D are critical for the proper functioning of the innate immune system, our body’s first defense. Vitamin D helps us fight off infection by bacterial, fungal, and viral invaders.[32] And it is widely understood that the seasonality of influenza correlates remarkably well with a seasonal drop in vitamin D levels in winter.[33]

Vitamin D can apparently pack a wallop against flu. In a remarkable 2015 letter to Canadian Family Physician, Gerry Schwalfenberg MD, writes that when his patients take supplements of Vitamin D, very few came down with influenza. “A colleague of mine and I have introduced vitamin D at doses that have achieved greater than 100 nmol/L in most of our patients for the past number of years,” he writes, “and we now see very few patients in our clinics with the flu or influenzalike illness.”[34]

Vitamin D functions best in conjunction with vitamin K, as they “talk” to each other through their receptors. Vitamin K supports vitamin D in many of its functions.[35] Menaquinone-7, or MK-7, is a highly bioactive form of vitamin K2 that pairs well with vitamin D3.[36]

Choose Rapid Action With Liposomal Formulations

When you get that pre-flu or cold feeling—that draggy, ‘fluey’ malaise before the virus is in full swing and the symptoms blossom—you will want rapid action from your herbal and vitamin arsenal. Liposomal formulations have been shown to offer almost instantaneous intra-oral absorption, with documented higher and sustained blood levels.

Liposomes are single to multilayer spheres made of phospholipids, the basic building blocks of cell membranes. They have been shown to cross the blood-brain barrier, deposit their cargo intracellularly, and support lymphatic circulation of therapeutic molecules. Smaller liposomes are more efficient at delivering compounds. In a study with liposomes of different sizes, cellular uptake of a liposomal formulation increased 9-fold as liposome size decreased. At the smallest size, cellular uptake was 34 times higher.[37]

Stride into cold and flu season this winter armed with superior protection!


You may also be interested in:

Rest, Repair, Recover!

Vitamin C versus Vitamin C with R-Lipoic Acid: Which Best Fits Different Clinical Settings?

Everybody’s Talking about Liposoms: Here’s What You Need to Know


[1]Fendrick AM e al. The economic burden of non-influenza-related viral respiratory tract infection in the United States, JAMA Internal Medicine. 2003; (163):4, pp. 487–494.
[2]Blanco N. et al. What Transmission Precautions Best Control Influenza Spread in a Hospital? Am J Epidemiol. 2016 Jun 1;183(11):1045-54.
[3]Hemilä H et al. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2013 Jan 31;1:CD000980.
[4]Hemilä H. Vitamin C and common cold incidence: a review of studies with subjects under heavy physical
stress. Int J Sports Med. 1996 Jul;17(5):379-83.
[5]Shaik-Dasthagirisaheb YB, et al. Role of vitamins D, E and C in immunity and inflammation. J Biol Regul
Homeost Agents. 2013; 27(2):291-295
[6]Bergsten P et al. Millimolar concentrations of ascorbic acid in purified human mononuclear leukocytes. Depletion and reaccumulation. J. Biol. Chem. 1990, 265, 2584–2587
[7]Anderson, R. Ascorbate-mediated stimulation of neutrophil motility and lymphocyte transformation by
inhibition of the peroxidase/H2O2/halide system in vitro and in vivo. Am. J. Clin. Nutr. 1981, 34, 1906–1911.
[8]Fisher BJ et al. Mechanisms of attenuation of abdominal sepsis induced acute lung injury by ascorbic acid. Am. J. Physiol. Lung Cell. Mol. Physiol. 2012, 303, L20–L32.
[9]Englard S et al. The biochemical functions of ascorbic acid. Annu. Rev. Nutr. 1986, 6, 365–406.
[10]Sen CK et al. Antioxidant and redox regulation of gene transcription. FASEB J. 1996, 10, 709–720.
[11]Stone, I. The Healing Factor: Vitamin C against disease. Foreward Linus Pauling. Available at:, Accessed January 22, 2019
[12]Levine, SL et al. Antioxidant Adaptation: Its Role in Free Radical Pathology. Allergy Research Group 1994.
[13]Marik PE. Vitamin C for the treatment of sepsis: The scientific rationale. Pharmacol Ther. 2018 Apr 21
[14]Packer L, et al. Molecular aspects of lipoic acid in the prevention of diabetes complications. Nutrition 2001;17:888-895
[15]Carreau JP. Biosynthesis of lipoic acid via unsaturated fatty acids. Methods Enzymol. 1979;62:152-158
[16]Bustamante J et al. Alpha-lipoic acid in liver metabolism and disease. Free Radic Biol Med. 1998;24(6):1023-1039.
[17]Wesselink E. et al. Feeding mitochondria: Potential role of nutritional components to improve critical illness convalescence. Clin Nutr. 2018 Aug 31. pii: S0261-5614(18)32426-9.
[18]Moura FA et al. Lipoic Acid: its antioxidant and anti-inflammatory role and clinical applications. Curr Top Med Chem. 2015;15(5):458-83.
[19]Packer L et al. Neuroprotection by the metabolic antioxidant alpha-lipoic acid. Free Radic Biol Med. 1997;22(1-2):359-78.
[20]Moura FA. Lipoic Acid: its antioxidant and anti-inflammatory role and clinical applications.  Curr Top Med Chem. 2015;15(5):458-83.
[21]Dröge W  et al. Glutathione and immune function. Proc Nutr Soc. 2000 Nov;59(4):595-600.
[22]Fraternale A et al. Glutathione and glutathione derivatives in immunotherapy. Biol Chem. 2017 Feb 1;398(2):261-275
[23]Sinha R et al. Oral supplementation with liposomal glutathione elevates body stores of glutathione and markers of immune function. Eur J Clin Nutr. 2018 Jan;72(1):105-111.
[24]Keplinger K et al. Uncaria tomentosa (Willd.) DC. – ethnomedicinal use and new pharmacological, toxicological and botanical results
Journal of Ethnopharmacology, 1999 (64):23-34
[25]Sentore A et al. Phytochemical and biological research on Uncaria tomentosa L. Boll Soc Ital Biol Sper 1989;65:517-520.
[26]Lemarie K et al. Stimulation of interleukin-1 and -6 production in alveolar macrophages by the neotropical liana, Uncaria tomentosa (Uña de Gato). J Ethnopharmacol 2000;64:109-115.
[27]Lemarie K et al. Stimulation of interleukin-1 and -6 production in alveolar macrophages by the neotropical liana, Uncaria tomentosa (Uña de Gato). J Ethnopharmacol 2000;64:109-115.
[28]Lemaire I. Stimulation of interleukin-1 and -6 production in alveolar macrophages by the neotropical liana, Uncaria tomentosa (uña de gato) J Ethnopharmacol. 1999 Feb;64(2):109-15.
[29] Sheng Y et al. Enhanced DNA repair, immune function and reduced toxicity of C-MED-100*, a novel aqueous extract from Uncaria tomentosa. J Ethnopharmacol. 2000 Feb;69(2):115-26.
[30]Allen-Hall L. Uncaria tomentosa acts as a potent TNF-alpha inhibitor through NF-kappaB. J Ethnopharmacol. 2010 Feb 17;127(3):685-93.
[31]Carlberg C et al. The first genome-wide view of vitamin D receptor locations and their mechanistic implications. Anticancer Res. 2012 Jan;32(1):271-82
[32]White JH. Vitamin D signaling, infectious diseases, and regulation of innate immunity. Infect Immun. 2008 Sep;76(9):3837-43
[33]Cannell JJ et al. Epidemic influenza and vitamin D. Epidemiol Infect 2006;134(6):1129-40.
[34]Schwalfenberg D, Vitamin D for influenza. Letters/Correspondence. Canadian Family Physician • Le Médecin de famille canadien. 2015 (61): p. 507
[35]Bügel S. Vitamin K and bone health in adult humans. Vitam Horm. 2008;78:393-416
[36]Schurgers LJ, et al. Vitamin K-containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. Blood. 2007;109:3279-83
[37]Hood, RR et al. Pharmacy on a chip: microfluidic synthesis of pegylated and folate receptor-targeted liposomes for drug delivery.  16th International Conference on Miniaturized Systems for Chemistry and Life Sciences. October 28 - November 1, 2012, Okinawa, Japan