Looking after your immune system is for life, not just for Covid 19 says immunologist Dr Jenna Macciochi. And it's easier than you think
How many of us have perhaps become ‘armchair immunologists’ over the course of the Covid pandemic? A year ago, most of us had never heard of viral load or herd immunity but now these terms are part of everyday conversations. It’s been a unique year for the immune system. But what exactly is it? How does it work, and is there anything we can do to strengthen or even ‘boost’ it?
We asked Dr Jenna Macciochi, immunologist researching the impact of diet and lifestyle on the immune system, personal trainer and mother of five-year-old twins to explain. Author of Immunity, The Science of Staying Well , she’s she is on a mission to decode exactly what it takes to be well in the modern-day and believes we can no longer ignore the fact that our fast-paced, over-consuming, unrelenting lives are slowly eroding our delicate immune defences.
“Although we often refer to the immune system as a single on-off switch, it’s not, in fact, one thing. And it’s not only in one place. A good way to start understanding it is to liken it to a castle with many layers of defence. That fortress includes your body’s borders as the first line of defence – things such as your skin and the lining of your mouth, nose, gut and lungs and the collection of good microbes that live on them that create a hostile environment for invaders or destroying them directly. It also includes special tissues and organs – including bone marrow, spleen and lymph nodes). It also includes the complex network of white blood cells, each with unique roles and functions that get involved at various stages of fighting an infection or disease. Collectively these components exist not only to protect us against the threat of invasion from bacteria, viruses, fungi and parasites, but also to repair and recycle damaged cells to defend us against other diseases such as cancer.
“Our white blood cells (and the molecules they produce) are made up of two parts: innate and adaptive immune cells and together they are your body’s safeguard. When a germ tries to infect us, innate immune cells raise an alarm within minutes activating a diverse squad of immune cells. This initial shotgun blast against infection is what you notice when you first get sick. Inflammation causes some of the familiar uncomfortable symptoms – stuffy nose, sore throat, fever.
“Adaptive immunity is more like a targeted missile and can take longer to kick in: five to seven days. Adaptive immunity is controlled by two types of lymphocytes (a type of white blood cell) T cells and antibody-producing B cells, which remember germs we have previously seen (vaccines work on this principle). An immune system that doesn’t produce a huger variety of unique T and B lymphocytes will probably miss or ‘not see’ certain germs of viruses and these could go on, unchallenged, to cause disease.
“Although military metaphors are often used to describe our immune defences, your immune system is more sophisticated than that. For every army, we also need peacekeepers. For that reason, one half of your immune system is actually designed to turn the other half off. So the last and often overlooked phase involves preventing the initial inflammation from running rampant and damaging our delicate tissues, keeping a few specialist T and B cells on tap in case the same germ tries to invade again.
“Our overall immunity is affected by a range of things, some we can’t control (like genetics) but many that we can. There are several ways we can support our immunity and guard against disease. Supporting a well-functioning immune system is one for the best things we can do for our health. Here are my top five easy way to do it."
1. Get a broad range of micronutrients.
“Vitamin C might have become the subject of faith early in the pandemic, but multiple micronutrients, including vitamins A, D, C, E, B6, and B12, folate, zinc, iron, copper, and selenium, each playing vital, often synergistic roles at every stage of the immune response.”
2. Take a vitamin D supplement
“Vitamin D certainly takes centre stage, with deficiency noted as a common risk factor for Covid 19 and shown to reduce its severity. With one in five of us at risk of low vitamin D, it’s something we should all be supplementing with. Adults and children should take 10mcg per day.” Try Healthspan Vitamin D3 10ug , 240 tablets, £8.95.
3. Keep your social networks strong
“A viral pandemic can make you sick, but so can loneliness and stress. There is also a growing science-based case for optimism, kindness and strong social networks in helping our immune system.”
4. Get out in nature and look after your sleep
"Fresh air, green space and sunlight are emerging as critical too. Sleep is one of the most important things we can do for optimal immune function.”
5. Exercise regularly
“Regular moderate physical activity is scientifically shown to be associated with better immune function, as well as lower levels of anxiety and perceived stress. So, it’s less ‘magic’ bullet, more a 360-degree lifestyle approach. Because caring for our immunity is for life, not just for Covid 19."
Dr Jenna Macciochi is an immunologist and an ambassador for wellbeing brand Healthspan .
Parkin J, Cohen B. An overview of the immune system. Lancet. 2001 Jun 2;357(9270):1777-89. doi: 10.1016/S0140-6736(00)04904-7. PMID: 11403834.
Gombart AF, Pierre A, Maggini S. A Review of Micronutrients and the Immune System-Working in Harmony to Reduce the Risk of Infection. Nutrients. 2020 Jan 16;12(1):236. doi: 10.3390/nu12010236. PMID: 31963293; PMCID: PMC7019735.
Allegra A, Tonacci A, Pioggia G, Musolino C, Gangemi S. Vitamin deficiency as risk factor for SARS-CoV-2 infection: correlation with susceptibility and prognosis. Eur Rev Med Pharmacol Sci. 2020 Sep;24(18):9721-9738. doi: 10.26355/eurrev_202009_23064. PMID: 33015818.
Entrenas Castillo M, Entrenas Costa LM, Vaquero Barrios JM, Alcalá Díaz JF, López Miranda J, Bouillon R, Quesada Gomez JM. "Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study". J Steroid Biochem Mol Biol. 2020 Oct;203:105751. doi: 10.1016/j.jsbmb.2020.105751. Epub 2020 Aug 29. PMID: 32871238; PMCID: PMC7456194.
Steven W. Cole, John P. Capitanio, Katie Chun, Jesusa M. G. Arevalo, Jeffrey Ma, John T. Cacioppo. Myeloid differentiation in social isolation. Proceedings of the National Academy of Sciences Nov 2015, 201514249; DOI: 10.1073/pnas.1514249112
Segerstrom SC, Miller GE. Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry. Psychol Bull. 2004;130(4):601-630. doi:10.1037/0033-2909.130.4.601
Besedovsky L, Lange T, Haack M. The Sleep-Immune Crosstalk in Health and Disease. Physiol Rev. 2019;99(3):1325-1380. doi:10.1152/physrev.00010.2018