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Let’s face it: No one likes being sick. Although it’s inevitable that you’ll come down with a cold, flu, or other virus at some point, a robust immune system can protect you from a variety of common ailments—and eating a diet rich in immune-boosting foods can help.
The immune system is a complex network in the body that’s affected by many factors, including age, genetics, environmental changes, and chronic diseases. But some lifestyle habits can also negatively impact your immune system. Top of the list? Your diet.
The foods you eat play a substantial role in either boosting or suppressing immunity. A diet full of whole foods and rich with fruits and vegetables provides many of the necessary nutrients your immune system needs to function optimally. In contrast, a diet of processed foods that’s high in added sugar, salt, and saturated fats and low in plant-based nutrition may actually weaken your body’s defenses against common viruses and infections.
A healthy diet starts in the grocery store. The food you bring into your home naturally becomes the food you eat. So, if you want to build a diet rich in immune-boosting foods, you have to be a savvy shopper.
While it can be tempting to stock up on the latest food trends, many of the best immune-boosting foods are also the most basic. As a registered dietician, here are the 10 items I always add to my cart to keep myself and my family healthy.
10 immune-boosting foods to add to your diet
Apples are both inexpensive and available almost everywhere year-round. It is not an exaggeration to say that I eat one every day. And you should, too.
Apples are high in vitamin C, potassium, and fiber, all essential immune-boosting ingredients. In addition, apples contain many phytochemicals, potent antioxidants and antivirals that support immune function.
Dark leafy greens
A bag of spinach or kale will only set you back a few bucks at the grocery store, but comes with a boost of immune-boosting power.
In addition to vitamins A, C, E, and K, dark leafy greens are high in fiber, folate, magnesium, and iron. The deep green color comes from the carotenoids zeaxanthin and lutein, strong antioxidants that prevent oxidative damage, a major stressor of the immune system.
This green vegetable contains almost as much vitamin C as an orange. Vitamin C is an essential nutrient for immune cell function. Many people load up on vitamin C at the first sign of a cold, but truthfully, the best protection comes from getting enough vitamin C every single day.
The tangy taste of sauerkraut is a result of fermentation, a natural process that produces live, active cultures of probiotics, similar to what you find in yogurt. But sauerkraut has a leg up on yogurt because it’s made from cabbage. Cabbage is in the same vegetable family as broccoli and provides many of the same health benefits. So, sauerkraut gives a one-two punch of nutrients plus probiotics that support a robust immune system.
Garlic contains a compound called allicin, a powerful antimicrobial and antiviral. When eaten regularly, garlic may enhance immune function, providing protection against viral infections and reducing the length of time you’re sick if you do catch something.
Over the winter months, when citrus is in season, I load up on some variety of these fruits every week. Citrus fruits are high in vitamin C and folate, as well as polyphenols that reduce inflammation in the body.
Also known as garbanzo beans, chickpeas are relatively inexpensive, easy to find, and have a long shelf life. But most importantly, they’re an immune-boosting superfood.
Chickpeas are high in prebiotic carbohydrates. Carbohydrates get a bad rap these days, but prebiotic carbohydrates are a type of fiber that feeds the good bacteria in your gut. A diet high in prebiotics encourages the growth of good bacteria that play a critical role in your immune system.
On the flip side, a diet short on prebiotics and fiber may impair immunity by creating an imbalance of bacteria and microbes in your gut. Chickpeas for the win!
Onions are an inexpensive and easy-to-find food that should absolutely make it into your shopping cart.
In addition to fiber and prebiotics, onions contain a hefty dose of quercetin, a powerful antibacterial and antioxidant agent. Regularly eating onions is also associated with a decreased risk of certain types of cancers.
The microbes in your digestive tract make up 70 percent of your immune system. For optimal immunity, you need a diverse, thriving community of bacteria, and that requires a diverse, prebiotic-rich diet.
Just like chickpeas, oats are an excellent source of prebiotics and fiber to support the disease-fighting bacteria in your gut. The prebiotic beta-glucan found in oats may enhance the responsiveness of your immune system, as well as decrease inflammation that may interfere with optimal immune function.
One cup of baked sweet potato provides over 700 percent of the Vitamin A your body needs. Vitamin A is essential for developing healthy immune cells, and it supports the integrity of the lining of the gut, your first line of defense against pathogens.
The deep orange or purple color of sweet potatoes comes from phytochemicals such as beta-carotene and anthocyanins. A diet rich in phytochemicals makes your immune system more effective while also reducing the risk of inflammatory and autoimmune conditions.