The immune system is a highly complex network of cells and molecules that work in concert with all parts of the body to respond to viruses, other pathogens, and various other chemical insults by producing antibodies and defensive cells. It’s not easy to pinpoint definitively what to eat or drink to make it stronger, which is why a well-rounded whole-food diet full of fresh vegetables, fruits, and grains is your best insurance.

In addition to a balanced diet, to support your immune system, it’s also important to avoid immune-damaging drinking habits while implementing healthy drinking habits. Here are some fluids to try to help your immune system stay robust. Read on, and for more on how to eat healthy, don’t miss 7 Healthiest Foods to Eat Right Now.

Drinking enough water every day is so critical to maintaining a healthy immune system. Every expert we contacted for this article on the best immune-boosting drinking habits said being well hydrated with plain water is the easiest and most important step you can take every day to protect yourself from illness. It’s right up there with getting 7 to 8 hours of sleep every night.

“Water supports the body’s detoxification process and oxygenating blood,” says registered dietitian nutritionist Isa Kujawski, RDN, MPH, founder of Mea Nutrition. “Water is necessary to produce lymph, the vehicle by which white blood cells and immune cells are transported throughout the body to destroy bacteria, viruses, and other foreign invaders. It’s also crucial for proper digestion, which allows the body to absorb key immune-supporting nutrients like vitamin C.”

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You can’t go wrong with making a habit of drinking hot herbal teas. Herbal teas strengthen your immune system while lowering inflammation caused by an overreactive immune response thanks to their vitamin C, D-limonene, vitamin A, catechins, and quercetins, says Carrie Lam, MD, a regenerative medicine specialist with Dr. Lam Coaching. Some of the best herbal teas include dandelion and rosehip teas.

Dandelion Tea: “Some research indicates that dandelion tea helps rid your body of toxins, thereby helping your immune system deal with infections,” says Dr. Lam. But make sure to consult your doctor before using it since dandelion is a strong diuretic that may interact with other medications, she warns.

Rosehip Tea: Rosehip tea contains vitamin C, quercetin, catechins, and ellagic acid, substances known to reduce oxidative stress and inflammation. To get the most benefit from your beverage, steep rosehips for 6 to 8 minutes, suggests a study in the Journal of Food Science Technology.

Lemon juice is high in famed antioxidant and immune-supporting nutrient vitamin C, and ginger is thought to have antioxidant and anti-inflammatory properties to strengthen immune defenses, says registered dietitian nutritionist Rachel Dykeman, MS, RDN, CDN. Vitamin C is famous for defending against illness because it enhances many cellular functions of the immune system and has been shown to prevent and treat respiratory and systemic infections.

Both lemon and ginger support the two parts of your immune system: your innate immunity, which is already in your body and responds immediately, and adaptive immunity, a long-lasting immune function created in response to exposure to a foreign substance like an invading pathogen.

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A big part of your immune system actually resides in your gastrointestinal tract, which is where the microbiome is located. One of the best ways to keep your microbiome healthy is by drinking kefir, a fermented beverage that’s like yogurt and contains live probiotics.

“A recent study in the journal Cell demonstrated that consuming probiotic-containing fermented foods and beverages, such as kefir, improves the diversity of microbes inhabiting our gut, in turn, impacting our immune system,” says Dyckman. “Other research suggests kefir may have anti-viral properties.”

Dyckman recommends choosing plain kefir to avoid the added sugars found in flavored varieties and says many commercially available brands are fortified with vitamin D, an immune regulating nutrient.

READ MORE: The Verdict on Taking Vitamin D Supplements for Your Immunity

Another powerful immune-boosting tea is turmeric tea, which contains a strong anti-inflammatory compound called curcumin. Dyckman recommends adding cracked black pepper to your turmeric tea because the compound piperine improves your body’s absorption of curcumin for a stronger anti-inflammatory effect.

Research shows that compounds in green tea increase the number of regulatory T cells that prevent autoimmune diseases as well as improve immune function. For “an unbeatable immune-boosting combination,” add lemon and a small amount of raw honey to your green tea, suggests Heather Hanks, MS, a nutritionist with USARX. “The vitamin C in lemon helps make the beneficial compound in the green tea move bioavailable and the honey contains antibacterial enzymes and prebiotic compounds to further boost immune health,” she says.

Jeff Hong, RD, a registered dietitian nutritionist with Yanre Strength advocates for orange juice, which is high in vitamin C, or warm apple cider mixed with a teaspoon of honey. “Apple cider is known to be antimicrobial; it can fight off bacteria, yeasts, and fungal infections,” Hong says. “The combo of cider and honey is an ancient remedy for fighting colds and flu and to boost the immune system.”

Two more fruits that are super high in vitamin C are strawberries and kiwifruit, which are perfect in “a smoothie to get a shot of immune-boosting vitamin C,” says Jamie Dickie, a nutritionist, and trainer with Truism Fitness. By making the smoothie with milk fortified with vitamin D, you get an extra immune (and protein) boost. “Many people are deficient in vitamin D, which you get mostly from sunlight; healthy levels minimize the risk of pneumonia and flu,” he says.

In a recent study in The BMJ, British researchers found that daily or weekly supplementation with vitamin D cut the risk of respiratory infection in half for people with the most significant deficiencies in vitamin D in their blood.

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