Taste the Rainbow: The Best Colorful Foods to Boost Immunity Naturally

Did you know that your immune system is like your very own knight in shining armor? It’s there to protect you from harmful substances, germs, diseases, and even cancer (1). But just like any organ in your body, your immune system needs to be taken care of in order to fend off all your foes! One of the best ways to boost your defenses is to consume a variety of naturally colorful foods loaded with vitamins and minerals (2). We at The Plug have provided you with a guide on how to truly taste the rainbow; by doing so, you give your immune system the strength it needs!

Red

● Red Bell Peppers: Just one of these mild peppers contain more vitamin C than two whole oranges, along with a substantial amount of beta-carotene (2). Vitamin C creates a strong barrier within your immune system and promotes skin health (3), while beta-carotene (which converts into vitamin A) can improve your blood cell function, helping to destroy bacteria (4). 

● Grapefruit: Starting your day off by eating grapefruit is a great way to increase your vitamin C intake! This vitamin increases the amount of white blood cells you produce and helps protect you from illnesses (2). 

● Salmon: This fatty fish is packed with omega-3 fatty acids, which sustain immune cells and contribute to heart and brain health (5, 6) – you don’t have to ask a sketchy wizard for those!

● Lobster/Crab: These types of shellfish contain zinc, which treats colds, assists in healing, and supports your metabolism (2, 7). 

Orange

● Oranges/Clementines/Tangerines: Orange you glad that these fruits are great for your well-being? These citruses are chock-full of vitamin C, which can help you recover from a cold faster (2). 

● Carrots: Aeugh! We recommend that you don’t feed these to a puffer fish, but you can eat them to improve your immunity! Carrots are a good source of many minerals, vitamins, and antioxidants, leading to a strong immune system (5, 8). The health of your eyes, heart, liver, and kidneys will be supported as well (5, 8)!

● Papaya: This tropical and floral-tasting fruit can provide you with your total daily recommended amount of vitamin C! Papaya also has anti-inflammatory effects, which can help with your digestive system (2). It contains several minerals too, such as potassium, magnesium, and folate – all of which support heart health (2). 

Yellow

● Ginger: Packing a punch in both taste and health benefits, ginger is anti-inflammatory and can decrease nausea (2). Having some ginger tea can help you get over a cold and minimize any pain – not to mention lowering your cholesterol (2)! And don’t forget: since 2024, The Plug Drink features ginger in its formula!

● Turmeric: Often used in curry, this spice is a wonderful anti-inflammatory that contains curcumin, a natural chemical with antimicrobial properties that assists your immune system (3). Needless to say, we’re glad that turmeric makes a powerful appearance in The Plug Pills!

● Lemon: This fruit may be sour, but its immune benefits are sweet! Similar to the other citrus fruits in our list, lemons are packed with vitamin C (5). Adding a sliced lemon to your tea or squeezing some lemon over your salmon can really go a long way!

Green

● Broccoli: This super veggie has a ton of different vitamins – namely, vitamin, A, C, and E, the last of which can enhance cell regeneration (2, 9). Broccoli also has antioxidants, which is great for immunity, and fiber, a mighty ally to gut health (10, 2). 

● Spinach: Popeye wasn’t playing around when he swallowed cans of spinach, and neither will your immune system when you get this leafy green into your diet! It contains the big three: vitamin C, antioxidants, and beta-carotene (2). In order to keep spinach’s nutrients intact, try eating it raw instead of cooking it (2). 

● Limes: Here we have another citrus fruit high in vitamin C (2) – but this time in neon green! Limes are great for adding to drinks or salad dressings. 

● Kiwi: This fuzzy fruit contains fundamental nutrients such as vitamin K, vitamin C, folate, and potassium (2). Vitamin K in particular affects plasma proteins in the blood, which affects your immune response (11). 

Blue

● Blueberries: Filled with antioxidants, vitamin A, and vitamin C, these little berries can reduce cell damage and boost your immune system (12). 

● Acai: Known as a superfood, these berries are known to have up to 10 times the antioxidant punch of blueberries while also having anti-inflammatory properties (13, 14). 

Keeping your immune system in tip-top shape is essential for your overall health, so keep it in check by eating a healthy and varied diet and taking The Plug! Don’t give nasty germs a chance to get into your fortress, PlugFAM – boost your immunity with this rainbow of foods this season! 

Bibliography 

1. In brief: How does the immune system work?. InformedHealth.org | Institute for Quality and Efficiency in Health Care (IQWiG) [Internet]. Updated 2023 June 6. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279364/ 

2. Schend J. 15 Foods That Boost the Immune System [Internet]. Healthline. Updated 2024 Jan 19. Available from: https://www.healthline.com/health/food-nutrition/foods-that-boost-the-immune-system 

3. Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients [Internet]. 2017 Nov 3;9(11): 1211. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5707683/ 

4. Chew BP. Role of Carotenoids in the Immune Response. Journal of Dairy Science [Internet]. 1993;76(9): 2804-2811. Available from: https://doi.org/10.3168/jds.S0022-0302(93)77619-5

5. Brown University Health Blog Team. Foods to Boost Your Immune System [Internet]. Brown University Health. 2022 July 5. Available from: https://www.lifespan.org/lifespan-living/foods-boost-your-immune-system

6. Gutiérrez S, Svahn SL, Johansson ME. Effects of Omega-3 Fatty Acids on Immune Cells. International Journal of Molecular Sciences [Internet]. 2019 Oct 11;20(20):5028. Available from: https://doi.org/10.3390/ijms20205028 

7. Mayo Clinic Staff. Zinc [Internet]. Mayo Clinic. Updated 2025 Mar 26. Available from: https://www.mayoclinic.org/drugs-supplements-zinc/art-20366112#:~:text=Zinc%2C%20a%20nutrient%20found%20throughout,meat%20and%20fortified%20breakfast%20cereals. 

8. Nelson A, Gatta F, Painter K, Gopal A. How Nutritious Are Carrots? [Internet]. WebMD. Updated 2024 Jan 25. Available from: https://www.webmd.com/food-recipes/benefits-carrots 

9. Lewis ED, Meydani SN, Wu D. Regulatory role of vitamin E in the immune system and inflammation. IUBMB Life [Internet]. 2019 Apr;71(4): 487-494. Available from: https://pubmed.ncbi.nlm.nih.gov/30501009/  

10. Bendich A. Physiological role of antioxidants in the immune system. Journal of Dairy Science [Internet]. 1993 Sept;76(9): 2789-2794. Available from: https://pubmed.ncbi.nlm.nih.gov/8227682/ 

11. Namazi N, Larijani B, Azadbakht L. Nutrition and Immunity. Switzerland: Springer Cham; 2019.

12. 6 foods to boost your immune system this cold and flu season [Internet]. Geisinger. 2022 Sept 5. Available from: https://www.geisinger.org/health-and-wellness/wellness-articles/2018/01/19/14/09/6-foods-to-boost-your-immune-system-through-cold-and-flu-season#:~:text=Blueberries,%2C%20dietary%20fiber%2C%20and%20manganese

13. Acai - Uses, Side Effects, and More [Internet]. WebMD. Available from: https://www.webmd.com/vitamins/ai/ingredientmono-1109/acai 

14. Hobbs H. 8 of the Healthiest Berries You Can Eat [Internet]. Healthline. Updated 2024 Nov 13. Available from: https://www.healthline.com/nutrition/8-healthy-berries