10 Best Immune-Boosting Foods To Help Colds, Flu & More 2023
There’s an increased interest in having a strong immune system to fight off disease. Our immune system consists of biological processes that help protect our bodies from anything that invades it. And even though this system is reliable, foods may play a role in assuring it has all the required nutrients to keep it strong.
Some nutrients in immune-boosting foods have the potential to protect the body from diseases. They also may be a part of the body’s mechanism of protection, and it is vital to include a variety of nutritious foods daily for this very reason.
10 Immune-Boosting Foods to Include in Your Diet
- Orange bell peppers
- Green tea
How Does The Immune System Work?
The immune system comprises multiple organs, including the thymus gland, tonsils, bone marrow, spleen, lymphatic vessels, lymph nodes, adenoids, and Peyer patches. This system protects us from outside invaders like bacteria, viruses, fungi, and toxins.
The main role of the immune system is to protect the body from infection or limit the condition. It recognizes unhealthy cells. It is important to note that our immune system is divided into two compartments: innate and adaptive.
- The first arm, the innate system, works as a rapid response system, recruiting immune cells to the site of infection or inflammation.
- The adaptive arm of the immune system is essential since it includes the immunological memory that develops after a response and offers long-term protection.
Important note: Supplements do not treat or cure diseases. Make sure to get your vaccines to keep you healthy during cold and flu season. As of yet, there is no evidence of using immune-boosting foods, superfoods, or supplements to prevent or treat Covid-19.
What Are Superfoods?
The superfoods title is awarded to foods that are rich in nutrients that may be beneficial to human health. Foods awarded the superfood title are varied. Some benefits attributed to superfoods are possible cancer prevention, antioxidant activity, improvement in glucose control, heart disease protection, and boosting the immune system, among others.
It is important to note that foods contain various nutrients that participate in the immune system functions. Foods also have components that have antioxidant and anti-inflammatory potential. The best way to keep up a strong immunity all year round is to eat a variety of fruits and vegetables daily.
10 Immune-Boosting Foods to Include in Your Diet
This dairy food contains probiotics that may help with maintaining a healthy gut microbiome. The microbiome (collection of microorganisms that live in our bodies) works as a barrier to pathogens. A poor diet may affect our bodies’ microorganisms, thus affecting immune response.
Probiotic foods like yogurt may have a role in maintaining healthy microorganisms in the body. This, in turn, might protect the intestinal barrier and suppress the growth of pathogenic agents. Avoid processed foods to prevent “bad bacteria” from overgrowing in your gut.
Around 5 ounces of Greek yogurt has 16 grams of protein. Make sure that your yogurt contains active cultures to get some healthy bacteria into your gut. This will help make sure you have good bacteria in your gut.
You can eat yogurt on its own or with some honey. Add fruits and nuts to it for more vitamins and fiber. Include them in your smoothies. You can use it as an ingredient in sauces or dressings like tzatziki (a salted yogurt, and cucumber dip).
Orange Bell Peppers
This vegetable is rich in vitamin C, with 3.5 ounces containing 263% of the daily value (DV). You can also find the green bell pepper contains around 165% of DV of vitamin C. This vitamin is not only a strong antioxidant; it participates in the cellular functions of the immune system. Vitamin C can also potentially prevent and treat respiratory conditions like the common cold. In addition, bell peppers also contain some vitamin B6 and zinc.
The best way to obtain nutrients from bell peppers is to eat them fresh. Include them in your salads, in your sandwiches or wraps, dip them into hummus, or pair them with your favorite salad dressings. Consider also including green, yellow, and red bell peppers to get a variety of colors on your plate and nutrients.
This root is used in Ayurvedic Medicine for its digestion and anti-inflammatory properties. Ginger contains bioactive compounds, like 6-gingerol, which, when extracted, presents some antioxidant, anti-inflammatory, and anticancer activities.
Ginger can be used to add flavor to your dishes like curries, stews, rice, and stir fry. You can also consume it as tea with some honey. This may be comforting, and the steam may be helpful with congestion.
Shellfish is a good source of zinc, an essential mineral that is part of many metabolic reactions. Zinc has a role in the cell-mediated immune response since the body needs it to create and activate T-lymphocytes or T-cells. These T-cells, one of the white blood cells, induce the death of target cells. In the shellfish group, 3 ounces of oysters offer 14 milligrams of zinc (94% DV). It is also a good source of iron, vitamin B-12, vitamin A, and folate.
A study worked on reviewing the evidence of zinc in the treatment of the common cold. It showed a possibility of it helping decrease the severity and duration of the cold when administered within 24 hours of symptoms. Although more investigation is needed on which form (lozenge vs. nasal gel) is most effective and its mechanism of action.
If not allergic, consider eating oysters in a soup, in a stew, in a paella, or on their own with a squirt of the citrus fruit lemon.
In Ayurveda, turmeric has many health benefits like cleaning the liver and blood. This plant, relative to ginger, is a spice that is considered a potent antioxidant and a superfood with anti-inflammatory properties.
It contains iron, zinc, folate, and vitamin E which is a fat-soluble vitamin and antioxidant. Curcumin, a compound in turmeric, interacts with various immune cells and modulators during an immune response. More investigation is needed to determine if it has a role in protecting cells from infections.
This spice herb can bring beautiful yellow color to your meals. Cook up curries, potatoes, and rice dishes, or sprinkle on your meat. You can also make golden milk or a cinnamon-turmeric tea to warm up during a cold.
Chicken soup is a traditional remedy for colds and flu. Its hot liquid and aromatic vegetables (celery, carrots, onions, mushrooms,…) may help with congestion relief. In addition, poultry is a source of protein and vitamin B6; this last one participates in the immune response. Protein provides the amino acids required to create antibodies.
In addition to the traditional chicken soup, try roasted poultry. Include this protein source in a stew, stir fry, or shredded on your salad. Add a variety of vegetables, herbs, and spices to your dishes to boost flavor instead of salt.
One cup of cubed papaya will contain around 88 milligrams (mg) of vitamin C (147% of DV). This fruit is also a good source of vitamin A and zinc. Vitamin A metabolites in the body may have a role in maintaining an intestinal immune response, which may decrease mortality from an intestinal infection. It will help keep a healthy immune system.
Papaya also contains the enzyme called papain. This enzyme works as a meat tenderizer but is also used to help with digestion. Pair up with whole grains like oatmeal to get more fiber and further boost digestive health.
Eat this fruit ripe and raw as part of a fruit salad or on top of your oatmeal. You can make smoothies or shakes. Some people eat it prepared from unripe (green) candied fruit. Be aware that this may have more sugar than recommended.
Note: Pregnant people should avoid unripe and uncooked papaya consumption due to its high latex content and being unsafe during pregnancy.
Broccoli is part of the cruciferous vegetable family, alongside kale and cabbage. It is not only a source of fiber but also other nutrients like folate, calcium, vitamin K, vitamin A, and vitamin C. One cup of raw broccoli has 81 grams (g) of vitamin C. It also has lutein and beta carotene (precursor of vitamin A), which has antioxidant properties and can be cell-protecting.
Ideally consume broccoli raw or steamed to retain most nutrients. Eat broccoli florets with a salad dressing. Chop up and add to your favorite salad. You can also make a slaw with this vegetable and top it with some pumpkin seeds.
If preparing, consider sauteeing with onion and garlic cloves for more flavor. Use healthy fat like olive oil for cooking or as a dressing. Pair up with sweet potatoes and fatty fish like salmon for a great meal.
This fruit tends to be avoided due to its hairy exterior. You should consider including it for its vitamin C content of 56mg (93% DV). It is also a source of lutein which may be important to maintaining eye health. A small study used gold kiwis as a supplement for participants with low vitamin C levels in the blood, with the result associating consumption with neutrophil function. Neutrophils are a type of white blood cell that scavenge and destroy the infection.
Enjoy this immune system booster fruit on its own when ripe. Cut it into wedges or slices to include in savory or sweet salads. Consider juicing it or in smoothies. Feel free to include it in a sandwich.
This tea contains Epigallocatechin-3-gallate (EGCG), a bioactive compound. Due to its polyphenols content, green tea may have antioxidant and anti-inflammatory activity. It may be a good food to keep your immune system strong.
Consume this tea on its own or with some honey. Make sure to read the instructions for preparing each tea infusion.
Important to note that this is not a comprehensive list. Many foods may have immune-boosting functions in the body. At this time, we don’t have a clear mechanism on how each may work. It will be important to include a wide variety of foods to support immune health.
Other Ways To Boost Immune System
Moderate exercise is beneficial in protecting the immune system from changes during aging. This effect has not been found with more strenuous activity. Exercising regularly, 30-minute sessions, every day, may help boost your immunity.
Nutrients are transported throughout our body via the bloodstream. Water is important for the transport of nutrients to the organs but also for detoxification. Avoid sugary drinks. Drink mainly water, no-sugar-added drinks, or tea.
Getting adequate sleep may also be a factor in maintaining strong immunity. Studies associate sleep loss and short sleep duration with decreased immune function and increased inflammation.
According to the Center for Disease Control and Prevention (CDC), vaccines are a way to create disease-specific antibodies. They work to prime the body for when and if exposed to the disease, the body will be able to fight it.
A healthy diet plays a role in maintaining adequate immune responses and protection against infectious diseases. Some immune boosting foods may have components that play a part in different mechanisms of the immune system thus boosting immunity.
A healthy lifestyle that includes a diet rich in fresh foods, adequate sleep, proper hydration, and physical activity might increase your body’s ability to fight inflammation and bacterial and viral infections. Including a variety of superfoods in a balanced diet will help with overall health and immune function.
+ 24 sources
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- Anon, (2022). Seasonal Flu Vaccines. [online] Available at: https://www.cdc.gov/flu/prevent/flushot.htm
- Lambring, C.B., Siraj, S., Patel, K., Sankpal, U.T., Mathew, S. and Basha, R. (2019). Impact of the Microbiome on the Immune System. Critical Reviews in Immunology, [online] 39(5), pp.313–328. doi:10.1615/critrevimmunol.2019033233.
- Maldonado Galdeano, C., Cazorla, S., Lemme Dumit, J., Vélez, E. and Perdigón, G. (2019). Beneficial Effects of Probiotic Consumption on the Immune System. Annals of Nutrition and Metabolism, [online] 74(2), pp.115–124. doi:10.1159/000496426.
- Center (2022). Daily Value on the New Nutrition Facts Label. [online] U.S. Food and Drug Administration. Available at: https://www.fda.gov/food/new-nutrition-facts-label/daily-value-new-nutrition-and-supplement-facts-labels
- Carr, A. and Maggini, S. (2017). Vitamin C and Immune Function. Nutrients, [online] 9(11), p.1211. doi:10.3390/nu9111211.
- Wang (2014). Biological properties of 6-gingerol: a brief review. Natural product communications, [online] 9(7). Available at: https://pubmed.ncbi.nlm.nih.gov/25230520/
- Lahat, N., Shapiro, S. and Lerner, A. (1999). Celiac Disease—An Autoimmune Entity? The Decade of Autoimmunity, [online] pp.269–275. doi:10.1016/b978-044482824-8/50033-6.
- National Institutes of Health (2016). Zinc. [online] Nih.gov. Available at: https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/.
- Hulisz, D. (2004). Efficacy of Zinc Against Common Cold Viruses: An Overview. Journal of the American Pharmacists Association, [online] 44(5), pp.594–603. doi:10.1331/1544-3184.108.40.2064.hulisz.
- Momtazi-Borojeni, A.A., Haftcheshmeh, S.M., Esmaeili, S.-A., Johnston, T.P., Abdollahi, E. and Sahebkar, A. (2018). Curcumin: A natural modulator of immune cells in systemic lupus erythematosus. Autoimmunity Reviews, [online] 17(2), pp.125–135. doi:10.1016/j.autrev.2017.11.016.
- Chicken Soup Cure May Not be a Myth. (2003). The Nurse Practitioner, [online] 28(6), p.16. doi:10.1097/00006205-200306000-00005.
- Stach, K., Stach, W. and Augoff, K. (2021). Vitamin B6 in Health and Disease. Nutrients, [online] 13(9), p.3229. doi:10.3390/nu13093229.
- Li, P., Yin, Y.-L., Li, D., Woo Kim, S. and Wu, G. (2007). Amino acids and immune function. British Journal of Nutrition, [online] 98(2), pp.237–252. doi:10.1017/s000711450769936x.
- Mora, J.R., Iwata, M. and von Andrian, U.H. (2008). Vitamin effects on the immune system: vitamins A and D take centre stage. Nature Reviews Immunology, [online] 8(9), pp.685–698. doi:10.1038/nri2378.
- Amin, I., Ahmed, N., Kamal, H. and Mansoor, S. (2021). Geminiviruses and their interaction with host proteins. Plant Virus-Host Interaction, [online] pp.191–229. doi:10.1016/b978-0-12-821629-3.00024-5.
- Adebiyi (2021). Papaya (Carica papaya) consumption is unsafe in pregnancy: fact or fable? Scientific evaluation of a common belief in some parts of Asia using a rat model. The British journal of nutrition, [online] 88(2). doi:10.1079/BJNBJN2002598.
- Milani, A., Basirnejad, M., Shahbazi, S. and Bolhassani, A. (2016). Carotenoids: biochemistry, pharmacology and treatment. British Journal of Pharmacology, [online] 174(11), pp.1290–1324. doi:10.1111/bph.13625.
- Usda.gov. (2022). FoodData Central. [online] Available at: https://fdc.nal.usda.gov/fdc-app.html#/food-details/1102667/nutrients
- Bozonet, S., Carr, A., Pullar, J. and Vissers, M. (2015). Enhanced Human Neutrophil Vitamin C Status, Chemotaxis and Oxidant Generation Following Dietary Supplementation with Vitamin C-Rich SunGold Kiwifruit. Nutrients, [online] 7(4), pp.2574–2588. doi:10.3390/nu7042574.
- Wang, S., Li, Z., Ma, Y., Liu, Y., Lin, C.-C., Li, S., Zhan, J. and Ho, C.-T. (2021). Immunomodulatory Effects of Green Tea Polyphenols. Molecules, [online] 26(12), p.3755. doi:10.3390/molecules26123755.
- Forte, P., Branquinho, L. and Ferraz, R. (2022). The Relationships between Physical Activity, Exercise, and Sport on the Immune System. International Journal of Environmental Research and Public Health, [online] 19(11), p.6777. doi:10.3390/ijerph19116777.
- Mayo Clinic. (2021). How much exercise do you really need? [online] Available at: https://www.mayoclinic.org/healthy-lifestyle/fitness/expert-answers/exercise/faq-20057916.
- Irwin, M.R., Witarama, T., Caudill, M., Olmstead, R. and Breen, E.C. (2015). Sleep loss activates cellular inflammation and signal transducer and activator of transcription (STAT) family proteins in humans. Brain, Behavior, and Immunity, [online] 47, pp.86–92. doi:10.1016/j.bbi.2014.09.017.
- Anon, (2022). Immunization Basics. [online] Available at: https://www.cdc.gov/vaccines/vac-gen/imz-basics.htm