The COVID-19/ Coronavirus outbreak has been declared a pandemic by the World Health Organization (WHO) and is affecting each and every one of us, in one way or another. In these uncertain times, we know you want to give yourself and your family the upper hand and maybe looking to the media to provide you with some guidance on what to eat or what supplements to take to ‘boost’ your immune system.
The first thing I want to clear up is that there is no way to ‘boost’ your immune system through diet and unfortunately there is no specific food or supplement that will prevent you catching COVID-19/ Coronavirus. It is of vital importance to remember that good hygiene (like washing and sanitizing your hands) is the best way that you can avoid infection and help to control the spread. We can try our best to look after ourselves and avoid seasonal colds and flu, in an effort to reduce the additional impact this could have on our healthcare systems.
The best way to protect against seasonal flu is:
- Get a flu vaccine- Remember that the flu vaccine does not give you the flu!
- Staying away from others who are sick and take care to not infect others if you’re sick (i.e. practice self-isolation and social distancing)
This being said, there are a number of nutrients that are necessary for the optimal functioning of your immune system (including copper, folate, iron, selenium, zinc and vitamins A, B6, B12, C and D). All these nutrients work in synergy with one another in the context of a balanced diet to fight infections and prevent disease.
Foods that provide a good balance of both macro (carbs, protein and fat) and micronutrients (vitamins and minerals) are a must on a regular basis. The focus should be on lean proteins, whole grains and high fibre starches, plant fats, fruits and vegetables, all in their most natural form (ie minimally processed).
Supplements in relation to COVID-19/ Coronavirus are currently not well understood, however when it comes to the common cold and yearly flu, the following information may be helpful:
Vitamin C is found in many fruits and vegetables. Some of the best sources are sweet peppers, strawberries, kiwi, oranges and broccoli. If you don’t eat enough vitamin C-rich foods, you can also take a supplement. You need about 200mg on a daily basis to help fight colds. This dose may slightly reduce the duration and severity of cold symptoms. However, if you are an athlete or experience extreme physical stress may reduce the incidence of colds by as much as 50%. A higher dose of this (1-8 g/day) once a cold is already present does not appear to be beneficial on the duration or severity of symptoms when compared to placebo.
Zinc is a mineral that’s found in oysters, fish, seafood, beef, pumpkin seeds and baked beans. It is also found in zinc lozenges, syrup and supplements. Taking a zinc supplement within 24 hours of getting a cold may help you have fewer symptoms. The recommended dose is not yet known. Speak with your doctor or pharmacist for more advice. Do not take more than 40mg per day as this may not be safe. Also, do not use a zinc nasal spray as it may cause a loss of smell.
Probiotics: Probiotics are good bacteria that help keep your immune system healthy. To fight colds, you need about 10 billion active probiotic cultures per day. This amount can be taken through supplements or in food (like yoghurt or fermented foods). To help fight colds, you have to take probiotics every day for at least three months before the cold season begins.
Does sugar influence my immunity?
While there is insufficient evidence to suggest that sugar consumption directly influences the immune system, obesity has been found to impair the immune system leading to an increased risk for infections. In general, foods that are energy-dense, but nutrient-poor should be avoided to prevent excessive weight gain and malnutrition. These include junk foods, takeaways and sugary foods and drinks.
There are a number of articles and blog posts that promote specific foods and supplements that claim to help you fight/ prevent COVID-19/ Coronavirus. Beware of misinformation and see warning lights if there is an affiliate link promoting or selling specific products to ‘cure’ or ‘treat’ the virus. These are uncertain times and there are people all over the world trying to capitalise on this pandemic through fear-mongering. For trustworthy information, keep an eye on health authorities (like the WHO) for continuous, evidence-based updates.
If you are looking for ways to upskill yourself (or even just keep you busy while you self-isolate) and want to learn more about nutrition and the role it plays in good health, go ahead and enrol in the Shaw Academy Nutrition Course, designed and presented by me, Abby Courtenay (Registered Dietitian). Our evidence-based online nutrition course aims to create a strong foundation on which you can build your nutrition knowledge. The beauty of online learning is that, not only can you increase your skills, but you can do so at your own time and pace at home. Enrol now! We look forward to seeing you at our next class!
- Practice-based Evidence in Nutrition: Immune System: Key practice points. http://www.pennutrition.com/KnowledgePathway.aspx?kpid=16006&pqcatid=146&pqid=18107
- Practice-based Evidence in Nutrition: Tips for staying well during cold and flu season. https://www.pennutrition.com/KnowledgePathway.aspx?kpid=16006&trid=18906&trcatid=467
- WHO myth-busting: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/myth-busters