Are You Ready for Cold and Flu Season?….some things to consider

Dr. Lisa Polinsky, ND


With the recent change to colder temperatures and shorter days we are now in the season of increased frequency of colds and flus. You may notice people around you with runny noses, congestion, coughs, sneezing and red, irritated eyes. Many people wait until it is too late but now is the time to take some steps and ramp up a preventive strategy.


Colds and flus are both caused by viral infections and increases in incidence are typically noted between October and May. The common cold usually lasts about 7 days with milder symptoms such as runny nose, increased mucus production, fatigue, red eyes, cough and sore throat. Influenza (‘the flu’) is much more serious and can involve prolonged symptoms of cough, congestion, fever, body aches and chills, fatigue to the point of exhaustion, shortness of breath and can lead to severe complications in susceptible individuals including pneumonia, hospitalization, dehydration and death. Several flu strains are implicated each year and as a result of viral mutation more severe flu strains can erupt. The viral strain H3N2 which circulated last year has been more virulent and longer lasting than the prior H1N1 viral strains leading some experts to predict the 2019/2020 season may also be of higher overall incidence. Your best strategy is to begin prevention now and help your immune system do its utmost.


We have two main branches of our immune system: 1) Aquired or Specific Immunity which includes the body’s production of specific antibodies in response to a foreign substance or antigen (ie in response to a flu shot or prior flu exposure) and 2) Innate Immune System which include defences such as physical barriers, inflammation or general immune responses. Innate Immune system barriers include your skin, mucus production, gastric acid, gut-associated lymphatic tissue in your digestive system, and the ability to mobilize a fever to kill viruses. Preventive strategies aimed at supporting both branches of the immune system are ideal. The following are some steps to consider in your preventive strategy. The standard recommendation at this time of year for prevention is the annual flu shot.  This article is to expand upon how the immune system is influenced in many ways in addition to the standard approach. For optimal care, book an appointment with your naturopathic doctor to create a personalized prevention protocol.



  • Hand-washing: is of utmost importance to keep viral (and bacterial) particles away from mucus membranes or from spreading to others. Washing for twenty seconds duration or the time it takes to sing “Happy Birthday” is recommended
  • Good Sleep: greater than 8 hours of sleep is important to support healthy immune function.1,2.
  • Stress Reduction: increased stress wreaks havoc on our immune function so any way to mitigate stress response is encouraged. Some options are yoga, meditation, cognitive behavioural therapy, mindfulness and potentially supportive vitamins and herbal formulas.3



  • Garlic: is a potent antiviral, antibacterial and antifungal powerhouse partly due to the compounds allicin and alliion. Raw is more potent than cooked though both can be helpful.
  • Increased fruits and vegetables: In one study those eating the most fruits and vegetables compared to other pregnant women had the lowest incidence of respiratory tract infections.4 The colourful component of fruits and vegetables included carotenoids which enhance Vitamin A levels as a possible mechanism of action.5
  • Green Tea: A flavonoid called catechin is a component of the active, healthful benefit of green tea consumption and has been observed to be antiviral in nature. There are many other healthful benefits to green tea including the calming support of theanine.6



  • Vitamin D: We have long observed lower rates of upper respiratory infections in drier, sunny climates and Vitamin D has a large role to play.7,8 Ideally, have your Vitamin D level tested (25-OH Vit D) via blood test to determine appropriate supplementation recommendations. When shadows are longer than your body height you can no longer synthesize Vitamin D from sun exposure so from October to May in Canada it is very hard to maintain adequate Vitamin D levels without supplementation.
  • Zinc: Many people are deficient in zinc and it plays a potent antiviral, immunestimulating effect due to many aspects. It increases macrophages, T and B cells and supports barrier immune function. White spots on your finger nails could be indicative of low zinc. Stress significantly depletes zinc.9
  • Probiotics: We know that 70-80% of our immune system resides in our gut and are still learning about the role of probiotics in immune regulation. Viral immune defence activation is one of the observed qualities of the lactobacillus species of probiotics.10 In my practice I have witnessed this combinations of nutrients as very helpful to both prevent and lessen severity of illness. It has been found that a person taking these nutrients at the same time as receiving an annual flu shot has resulted in enhanced host immune response to the vaccine, thereby rendering it more effective.


Prevention is always your best strategy in all areas of health but this is particularly true for seasonal colds and flus. There are a number of more detailed preventive measures that can be recommended by your naturopathic doctor in an individualized appointment. If you had a difficult time last year, tend to get more frequent colds, have had difficulty overcoming a recent cold, or have other chronic health conditions then further support is encouraged.


To monitor weekly incidence in your region keep this link handy. It outlines the number of cases and which strains of flu are particular active in a given region: https:// weekly-influenza-reports.html Unsure the difference between a cold and a flu virus? Click here: https://



  1. Prather AA, Leung CW. Association of Insufficient Sleep With Respiratory Infection Among Adults in the United States. JAMA Intern Med. 2016 Jun 1;176(6):850-2.
  2. Cohen S, Doyle WJ, Alper CM, Janicki-Deverts D, Turner RB. Sleep habits and susceptibility to the common cold. Arch Intern Med 2009;169:62-7.
  3. Segerstrom SC, Miller GE. Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry. Psychol Bull. 2004 Jul;130(4):601-30.
  4. Li L, Werler MM. Fruit and vegetable intake and risk of upper respiratory tract infection in pregnant women. Public Health Nutr. 2010 Feb;13(2):276-82.
  5. Gibson A, Edgar JD, Neville CE, Gilchrist SE, McKinley MC, Patterson CC, Young IS, Woodside JV. Effect of fruit and vegetable consumption on immune function in older people: a randomized controlled trial. Am J Clin Nutr 2012 Dec;96(6):1429-36. doi: 10.3945/ajcn.112.039057. Epub 2012 Nov 7.
  7. Martineau AR, Jolliffe DA, Hooper RL, Greenberg L, Aloia JF, Bergman P, DubnovRaz G, Esposito S, Ganmaa D, Ginde AA, Goodall EC, Grant CC, Griffiths CJ, Janssens W, Laaksi I, Manaseki-Holland S, Mauger D, Murdoch DR, Neale R, Rees JR, Simpson S Jr, Stelmach I, Kumar GT, Urashima M, Camargo CA Jr. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ. 2017 Feb 15;356:i6583.