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15 Foods That Boost the Immune System
Immune system boosters
Feeding your body certain foods may help keep your immune system strong.
If you’re looking for ways to prevent colds, the flu, and other infections, your first step should be a visit to your local grocery store. Plan your meals to include these 15 powerful immune system boosters.
An important note
No supplement will cure or prevent disease.
With the 2019 coronavirus COVID-19 pandemic, it’s especially important to understand that no supplement, diet, or other lifestyle modification other than physical distancing, also known as social distancing, and proper hygiene practices can protect you from COVID-19.
Currently, no research supports the use of any supplement to protect against COVID-19 specifically.
1. Citrus fruits
Most people turn straight to vitamin C after they’ve caught a cold. That’s because it helps build up your immune system.
Vitamin C is thought to increase the production of white blood cells, which are key to fighting infections.
Almost all citrus fruits are high in vitamin C. With such a variety to choose from, it’s easy to add a squeeze of this vitamin to any meal.
Popular citrus fruits include:
- 75 mg for women
- 90 mg for men
If you opt for supplements, avoid taking more than 2,000 milligrams (mg) a day.
2. Red bell peppers
If you think citrus fruits have the most vitamin C of any fruit or vegetable, think again. Ounce for ounce, red bell peppers contain almost 3 times as much vitamin C (127 mg) as a Florida orange (45 mg). They’re also a rich source of beta carotene.
Broccoli is supercharged with vitamins and minerals. Packed with vitamins A, C, and E, as well as fiber and many other antioxidants, broccoli is one of the healthiest vegetables you can put on your plate.
Garlic is found in almost every cuisine in the world. It adds a little zing to food and it’s a must-have for your health.
Early civilizations recognized its value in fighting infections. Garlic may also slow down hardening of the arteries, and there’s weak evidence that it helps lower blood pressure.
Garlic’s immune-boosting properties seem to come from a heavy concentration of sulfur-containing compounds, such as allicin.
Ginger is another ingredient many turn to after getting sick. Ginger may help decrease inflammation, which can help reduce a sore throat and inflammatory illnesses. Ginger may help with nausea as well.
While it’s used in many sweet desserts, ginger packs some heat in the form of gingerol, a relative of capsaicin.
Spinach made our list not just because it’s rich in vitamin C — it’s also packed with numerous antioxidants and beta carotene, which may both increase the infection-fighting ability of our immune systems.
Similar to broccoli, spinach is healthiest when it’s cooked as little as possible so that it retains its nutrients. However, light cooking makes it easier to absorb the vitamin A and allows other nutrients to be released from oxalic acid, an antinutrient. Check out some spinach recipes here.
Try to get plain yogurts rather than the kind that are flavored and loaded with sugar. You can sweeten plain yogurt yourself with healthy fruits and a drizzle of honey instead.
Yogurt can also be a great source of vitamin D, so try to select brands fortified with this vitamin. Vitamin D helps regulate the immune system and is thought to boost our body’s natural defenses against diseases.
When it comes to preventing and fighting off colds, vitamin E tends to take a backseat to vitamin C. However, this powerful antioxidant is key to a healthy immune system.
It’s a fat-soluble vitamin, which means it requires the presence of fat to be absorbed properly. Nuts, such as almonds, are packed with the vitamin and also have healthy fats.
9. Sunflower seeds
Sunflower seeds are also incredibly high in selenium. Just 1 ounce contains nearly half the selenium that the average adult needs daily. A variety of studies, mostly performed on animals, have looked at its potential to combat viral infections such as swine flu (H1N1).
You may know turmeric as a key ingredient in many curries. This bright yellow, bitter spice has also been used for years as an anti-inflammatory in treating both osteoarthritis and rheumatoid arthritis.
Research shows that high concentrations of curcumin, which gives turmeric its distinctive color, can help decrease exercise-induced muscle damage. Curcumin has promise as an immune booster (based on findings from animal studies) and an antiviral. More research is needed.
11. Green tea
In studies, EGCG has been shown to enhance immune function. The fermentation process black tea goes through destroys a lot of the EGCG. Green tea, on the other hand, is steamed and not fermented, so the EGCG is preserved.
Green tea is also a good source of the amino acid L-theanine. L-theanine may aid in the production of germ-fighting compounds in your T cells.
Papaya is another fruit loaded with vitamin C. You can find double the daily recommended amount of vitamin C in a single medium fruit. Papayas also have a digestive enzyme called papain that has anti-inflammatory effects.
Vitamin C boosts the white blood cells to fight infection, while kiwi’s other nutrients keep the rest of your body functioning properly.
When you’re sick and you reach for chicken soup, it’s more than just the placebo effect that makes you feel better. The soup may help lower inflammation, which could improve symptoms of a cold.
Vitamin B-6 is an important player in many of the chemical reactions that happen in the body. It’s also vital to the formation of new and healthy red blood cells.
Stock or broth made by boiling chicken bones contains gelatin, chondroitin, and other nutrients helpful for gut healing and immunity.
Zinc doesn’t get as much attention as many other vitamins and minerals, but our bodies need it so that our immune cells can function as intended.
Varieties of shellfish that are high in zinc include:
Keep in mind that you don’t want to have more than the daily recommended amount of zinc in your diet:
- 11 mg for adult men
- 8 mg for most adult women
Too much zinc can actually inhibit immune system function.
More ways to prevent infections
Variety is the key to proper nutrition. Eating just one of these foods won’t be enough to help fight off the flu or other infections, even if you eat it constantly. Pay attention to serving sizes and recommended daily intake so that you don’t get too much of a single vitamin and too little of others.
Eating right is a great start, and there are other things you can do to protect you and your family from the flu, cold, and other illnesses.
Medically reviewed by Amy Richter, RD— Written by James Schend
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