Practical Tips to Support a Healthy Immune System
Wondering what you can do to support your immune system? Here are some practical lifestyle factors to consider that may positively influence your immune response. Regular exercise, healthy eating and getting sufficient rest contribute to a balanced immune system. With the colder weather upon us, many of the patients I see are concerned about colds and influenza.
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 seven 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.
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 (e.g., 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. Strategies aimed at supporting both branches of the immune system are ideal. The standard public health recommendation for prevention of influenza is the annual flu shot. This article considers additional potentially helpful ways to support the immune system. These considerations are not intended to be specific to coronavirus; anyone in BC who suspects they may have coronavirus should call 811 immediately. Rather, these considerations are to assist individuals in preventing other types of viral infections that occur frequently at this time of the year.
Lifestyle:
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 eight 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 is encouraged. Some options are home yoga, meditation, cognitive behavioural therapy, mindfulness and potentially supportive vitamins and herbal formulas.3
Dietary:
Garlic: is a potent antiviral, antibacterial and antifungal powerhouse partly due to the compounds allicin and allion. Raw is more potent than cooked though both can be helpful.
Increased consumption of 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
Supplements:
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, immune-stimulating 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 It has been found that taking probiotics 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.
Vitamin C: Don’t forget about Vitamin C! Humans can’t synthesize vitamin C on our own and need to acquire it through our diet (similar to guinea pigs and chimpanzees). Studies show that for adults dosing greater than 2 gm per day can shorten the length and severity of upper respiratory infections as well as potentially lessen poorer outcomes.11
Updated from a 2019 Article
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.
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.
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.
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.
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.
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.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409678/