8 Foods That Strengthen Your Immune System

Surely you've heard the old saying, "an apple a day keeps the doctor away."  While a daily apple is a better strategy than nothing, it'll actually take a much stronger plan to really boost your immune system. Almost every year, we hear that this cold and flu season is predicted to be a doozy, and we're cautioned to be proactive to fight against germs. The best weapons in germ warfare are adequate sleep, regular exercise and appropriate hand washing.  But don't stop there: Give your immune system an all-natural "booster shot" by eating more of these readily-available, budget-friendly foods. 

Foods That Fight Colds & the Flu
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Sweet Potatoes do double-duty when it comes to fighting off infection. They're filled with beta-carotene, a powerful antioxidant that transforms into vitamin A, another antioxidant that keeps your skin strong and elastic, which helps keep those harmful bacteria and viruses out of your body.

Try It: Spicy Baked Sweet Potato Fries

Swap It: Other foods rich in these antioxidants include carrots, acorn squash, butternut squash and pumpkin.
Grapefruit is an excellent source of vitamin C, an antioxidant shown to attack free radicals and fight infection. Vitamin C it can lessen the time it takes your body to fight off a cold.  
Try It: Grapefruit Salad

Swap It: Other vitamin C-rich foods to try are oranges, tangerines, kiwis, bell peppers, papaya, strawberries and broccoli.
Almonds contain healthy omega-3 fats, as well as vitamin E, the fat-soluble vitamin that protects cells against oxidation and damage. Strong, healthy cells are definitely a boon to your immune system and can help your body defend itself against germs.

Try It: Maple Almond Granola
Swap It: Try peanut butter, olive oil, whole grains and seeds to get your vitamin E and healthy fats.
Salmon is a rich source of the mineral selenium, which works its magic as an antioxidant along with vitamin E. Together this duo protects cells from damage and stress that can make you susceptible to illness. 
Try It: Pistachio-Crusted Salmon

Swap It: If salmon's not your thing, you'll get the same benefits from other seafood, meats and whole grains. 
Roast beef is filled with zinc, which keeps your disease-fighting cells strong and healthy. This mineral is all about immune-system activation since it also promotes cell reproduction, growth and repair.
Try It: Beef and Broccoli

Swap It: Get your zinc on with wheat germ, pork, seafood or tofu
Yogurt is friendly for your gastrointestinal system—a key player in a healthy immune system. Your gut houses 25% of the immune cells in your body and provides 50% of your immune response. Plus it is home to more than 100 trillion helpful bacteria (also called probiotics). The live and active bacterial cultures found in yogurt gives these friendly bugs a boost, which can activate cells that kill viruses, fight colds and the flu, and decrease sick days. Tip: To keep these friendly bugs thriving, they need to be fed—fruits, veggies, beans and whole grains are some of their favorites.

Try It: Tzatziki (Yogurt Dip)

Swap It: Non-dairy yogurts made of coconut milk, soy milk or other ingredients will also do the trick; just make sure they contain the live and active cultures you're seeking. If yogurt isn't your favorite, try other fermented foods such as kefir, sauerkraut or miso.
Garlic not only adds amazing flavor to your foods but also gives your body allicin, an infection-fighting antioxidant that's been shown to help prevent cold and flu symptoms. Sautéed, roasted, grilled or raw---garlic can enhance your immunity.

Try It: Garlic-Spiked Broccoli and Mushrooms with Rosemary

Swap It: Onions, leeks and shallots are also members of the Allium family, along with garlic. They contain smaller amounts of allicin. 

Broccoli is an excellent source of folate, which plays an essential role in making new body cells—especially lymphocytes that search out and destroy harmful germs that invade your body.
Try It: Chicken and Broccoli Casserole

Swap It: If broccoli makes you cringe, get folate from spinach, Brussels sprouts, navy beans, avocado, oranges or peanuts.
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