If there’s one word that is at the tip of everyone’s tongue these days, it’s immune. Apart from social distancing measures, our immune systems are the only thing standing between us and the dreaded virus. So it makes sense to eat all the immune boosting foods we can to keep our bodies strong and healthy.
Before we jump to discussing immune system booster foods, it’s important to understand the role of your immune system.
How does the immune system work?
Your immune system is a network of cells, tissues and organs working together to keep out a host of invaders or foreign substances from taking over the body and causing harm.
The immune system is designed to protect you from these invaders and also to regulate the cell changes that are constantly happening in the body. This means that it can reduce the damage caused by a germ or pathogen by increasing the defence mechanisms of your body.
What are immunity boosting foods?
Immune boosting foods are nutrient-dense whole foods that feed the immune system and allow it to function at its optimal level. Their benefits come largely from the fact that they are nutritional powerhouses which deliver essential vitamins, minerals, antioxidants to the body to keep it running smoothly.
A majority of your infection-fighting bacteria live inside the digestive system, so consuming these foods is the simplest and best way to keep the immune system firing on all cylinders. A strong immune system works relentlessly to keep you free from diseases and ensure your health and well-being.
What is the relation between gut health and immunity boosting foods?
Most Aussies do not correlate the gut with the immune system but it has far more control over your immune system than you realize. With over 80% of your immune system located deep inside the digestive system, your gut is the largest single immune organ in your body.
Trillions of microbes, bacteria and viruses call the gut their home and function as an ecosystem, much like a rainforest. As a whole, this system is known as the gut microbiome. While researchers are still learning about microbiomes, it is known that good gut health is essential for an efficient immune system.
The balance of gut bacteria is determined by the kind of food you eat. When you eat immune boosting foods, the good bacteria break down the food and produce substances called short-chain fatty acids (SCFA). SCFAs are crucial in reducing inflammation which helps to keep the immune system in check. However, when the balance is tilted in the favor of the bad bacteria (when you eat unhealthy junk food, the gut suffers, causing lower immunity.
What kind of meals are considered part of immune boosting foods?
When trying to base your meals around immune boosting foods, follow one golden rule: colour. By ensuring that there is a variety of colour in your diet, you can be sure that you’re getting a good supply of key nutrients for immune support.
A good rule of thumb is to ensure that half your plate is filled with colourful fruits and vegetables to get the recommended daily nutrient intake.
Any food that is brightly coloured (as long as it is natural) is something that should be part of your diet. Look for food that is blue like blueberries, green like kale, yellow like squash, purple like aubergine and orange like carrots or sweet potatoes. Not only are these veggies and fruits teeming with vital vitamins and minerals to help boost immune function, they also have a number of phytonutrients which have immense antioxidant power.
It is quite easy to incorporate such foods into your diet. The best way is to eat them in their raw, natural state as a salad or add them to stir fry, stews, curries and soups. You could also drink your veggies and fruit by juicing them, but try to avoid eating only juiced or blended foods as you lose the pulp and fiber. Avoid overcooking vegetables because that is known to destroy essential vitamins and minerals. Try grating some of the vegetables into a salad or over your meals to add crunch and taste.
Which immunity system booster foods are best from each food group?
Among all the food groups, there are certain ingredients which lead the pack in terms of being immune system booster foods. This is due to their nutritional density and/or fiber content which boosts the gut and the rest of the immune system. Some of the best foods are:
- Green vegetables (broccoli, kale, spinach)
- Orange sweet potatoes
- Brown rice
- Whole wheat
- Low-fat yogurt
- Low-fat milk
Nuts and seeds
- Pumpkin seeds
- Sunflower seeds
Herbs and spices
What immunity boosting foods can I store for long-term usage?
The best way to eat immune boosting foods is as fresh and natural ingredients. Of course, that is not possible under all circumstances but do your best. If you can’t always access fresh fruit and vegetables, you can consider the following options that will last long-term:
- A range of nuts and seeds
- Frozen, tinned or packed versions of immune foods such as broccoli, corn, fruits and beans
- Cereals and wholegrain such as brown rice and wholemeal pasta,
- Tinned beans and lentils
- Tinned fish and frozen meat
What foods or practices can I follow besides eating immunity boosting foods?
While immune system boosting foods have their place in a healthy lifestyle, you also need a wholesome approach to living healthy and cultivating a sense of optimal wellbeing. Consider the following:
- Eat fermented foods such as kombucha, kimchi, yogurt, kefir and sauerkraut
- Limit caffeine consumption and focus on drinking water as well as herbal teas
- Limit stress and develop a practice to help you stay relaxed
- Reduce consumption of processed oils and fat; focus on healthier fats like avocados, nuts, olive oil and seeds
- Consume high quality oily fish rich in omega-3 fatty acids
- Avoid processed sugar and artificial sweeteners
- Dial down the alcohol consumption
- Eat for your gut by consuming plenty of dietary fiber from whole foods
- Subtract the additives that can be found in highly processed foods
What nutrients should I look for in immune system booster foods?
Immune foods stand out in terms of power because of the nutrients and minerals within them. Although a diverse range of nutrients is needed for optimal immunity, some are paramount to keep the system in harmony and ensuring that it is working efficiently. Try working on boosting these vitamins through the following:
Vitamin C has proven to be the superstar of the immune system. A powerful antioxidant, it is known to fight free radicals in the body and make immune cells. It is abundant in all fruits and vegetables but particularly good sources are:
- Citrus fruits
Vitamin A is a strong anti-inflammatory vitamin which is also vital in maintaining mucous membranes. Abundant sources of vitamin A are:
- Yellow fruits and vegetables
- Green and leafy vegetables,
Also known as the sunshine vitamin, vitamin D helps to stimulate as well as modulate the immune system. It prevents the system from overreacting, which can also cause extensive damage. While the sun is the best source of vitamin D, good food sources are:
- Cod liver oil
Zinc is critical to immune function for it helps mitigate susceptibility to infections and regulates the development and function of immune cells. Without zinc, the immune system cannot respond. It can be found in sufficient quantities in:
- Nuts and seeds
- Chickpeas, lentils and beans
Is there anything else to know about immune-boosting foods?
While it is absolutely critical to get sufficient quantities of nutrients and minerals for an efficient immune system, there is a possibility of overloading the system. Deficiency definitely has a detrimental effect on the immune system but so can high doses of vitamins or nutrients if you take more than required. This is why you should prevent overdoing the tablets or pills.
As far as possible, you should steer clear of supplementation whenever possible and instead focus on eating a balanced diet of whole foods. Ditch the supplements and focus on fruits, vegetables, wholegrain, legumes, nuts and seeds. Incorporate some of the immunity system booster foods within your diet from each of these groups to give that little extra for your immune health.
Do note that by increasing your immunity, you cannot avoid being infected by COVID-19 if you are exposed to it. However when your immune system is strong, you are strengthening your body’s defense mechanisms. With a stronger immune system, you’ll more likely to have milder symptoms.
If you would like to talk to a nutritionist, Avaana can help you find one near you.