Healthy Eating Best Healthy Foods 5 "Bad" Foods You Should Be Eating for a Healthy Immune System, According to Dietitians Fend off seasonal sniffles by stocking up on these “bad” foods that support your immune system. By Deborah Murphy, M.S., RDN Deborah Murphy, M.S., RDN Deborah Murphy is a food and nutrition blogger, recipe developer, content creator and consulting dietitian. She is an expert in plant-based nutrition and has more than 10 years of experience providing medical nutrition therapy for the geriatric population. EatingWell's Editorial Guidelines Published on September 18, 2024 Reviewed by Dietitian Karen Ansel, M.S., RDN Reviewed by Dietitian Karen Ansel, M.S., RDN Karen Ansel, M.S., RDN, is a nutritionist, journalist and author. In her 20-plus years of experience, she has written hundreds of health-focused articles about food, nutrition, fitness and wellness. Her work has appeared in EatingWell, Women's Health, Weight Watchers, Men's Health, Shape, Woman's Day, Prevention, Fitbit and other publications and websites. EatingWell's Editorial Guidelines Close With the return of cold and flu season, you may be wondering about the best way to fortify your immune system to fend off the sniffles. Of course, getting adequate rest, washing your hands and staying hydrated are a great start. But the real secret may be eating a balanced diet filled with immune-fortifying foods. The foods you eat can give your body the building blocks to create antibodies that defend against immune invaders like colds and viruses. You may already have some immune health all-stars like leafy greens, yogurt and salmon on your grocery list. But there are lots of “bad” foods you might be avoiding that are loaded with nutrients that can keep you off the couch and out of the doctor’s office. Really! Read on to learn the best dietitian-approved “bad” foods for a healthy immune system, plus quick, easy and tasty ways to enjoy them. 5 "Bad" Foods That Actually Support Immune Health 1. Eggs If you've been avoiding eggs because you've heard they're high in saturated fat and cholesterol, you don't have to. A large egg only contains 1.5 grams of saturated fat and a reasonable 186 milligrams of cholesterol. Immunity-wise, eggs are an affordable source of protein, a nutrient your body needs to create antibodies to ward off infection (6 g per large egg). Plus, they’re super easy to incorporate into loads of dishes. Eggs also provide other essential nutrients for a robust immune system, such as selenium, folate and vitamins A and D. In fact, eggs are one of the few foods that naturally contain vitamin D. They also supply small amounts of omega-3 fatty acids, which have also been linked with better immune health. Why not get a jump-start on strengthening your immune system by making eggs for dinner? What Happens to Your Body When You Eat Eggs Every Day 2. Potatoes Potatoes have been unfairly labeled a “bad” carb for years. The truth? “Potatoes can be a budget-friendly and easy food to support your immune system,” says Patricia Kolesa, M.S., RDN, founder of Dietitian Dish LLC. One medium potato delivers roughly 20% of the Daily Value for vitamin C, a key nutrient for immune health, she explains. Spuds also contain resistant starch, a type of carbohydrate that’s fermented by your gut bacteria. That’s good news, since a thriving gut microbiome is another way to strengthen your immune system (more on this soon!). What’s more, it’s easy to turn a simple baked potato into a healthy meal. In a hurry? Try potatoes roasted in a nutritious side dish like these Roasted Brussels Sprouts & Potatoes (it takes less than 30 minutes to make!). 3. Dairy Milk The endless array of nondairy milks and milk alternatives may have you wondering if dairy milk is good for you. When it comes to supporting your immune system, a glass of milk can do your body good. For example, this nutrient-dense beverage is a good source of protein (8 g per cup!). In addition, it also provides immune-supporting zinc and is fortified with vitamins A and D, which are all essential for keeping your immune system functioning at its best. When stocking up on milk, it may be worth spending a little more for organic milk. Studies suggest that organic milk may contain slightly higher levels of healthier fats like omega-3 polyunsaturated fats and conjugated linoleic acid (CLA)—a type of fat in dairy and beef that has been linked to better immune health. 4. Bananas Fending off the sniffles? Oranges aren’t the only fruit that can help you dodge a cold! Despite their controversial reputation for having too much sugar, bananas provide vitamin C and are an excellent source of vitamin B6, another nutrient that’s key for immune health. You might be surprised that the fiber in bananas (3 g per medium banana) may also keep your immune system strong. How’s that? Like potatoes, bananas contain resistant starch, which acts as a prebiotic, says Chelsea Newbrough, RDN, a gut health dietitian and founder of Rooting for Wellness Nutrition. “Prebiotics act as food for probiotics, the bacteria that live in our gut and support digestion and overall health,” she explains. “And maintaining a good healthy gut microbiome directly impacts your immune health, among many other things.” You already know bananas are a great snack, but why stop there? These healthy banana recipes are loaded with inspiration! 5. Breakfast Cereal Ready-to-eat breakfast cereal is the epitome of convenience. Lately, however, it seems to be on the no-no list for healthy eating. The truth? Cereal has lots of great things going for it, including keeping your immune system in tip-top shape. That’s because it’s often fortified with multiple immune-supporting nutrients like vitamin A, folate, zinc and iron. When buying breakfast cereal, keep in mind that nutrients can vary a lot. So you may want to follow a few guidelines when choosing yours. Specifically, look for cereals with at least 5 g of protein, 3 g of fiber and little-to-no added sugars. Of course, cereal is great topped with fortified milk and a sliced banana for a speedy breakfast or snack. But it’s also a win paired with unsweetened plain yogurt, like this Raspberry Yogurt Cereal Bowl. The Bottom Line Give your immune system the tools it needs to defend against infection this cold and flu season. A balanced diet will cover most of the bases for immune-boosting nutrients like protein, zinc and vitamins A, C and D. But don’t forget “bad” foods like eggs, potatoes, dairy milk, bananas and breakfast cereal. They may be just what you need for a battle-ready immune system. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources EatingWell uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable and trustworthy. U.S. Department of Agriculture. Food Data Central. Egg, whole, raw, fresh. Iddir M, Brito A, Dingeo G, et al. Strengthening the immune system and reducing inflammation and oxidative stress through diet and nutrition: considerations during the COVID-19 crisis. Nutrients. 2020; 12(6):1562. doi:10.3390/nu12061562 Myers M, Ruxton CHS. Eggs: Healthy or Risky? A Review of evidence from high quality studies on hen's eggs. Nutrients. 2023;15(12):2657. doi:10.3390/nu15122657 U.S. Department of Agriculture. 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