Immune system boosters

Feeding your body certain foods may help keep your immune system strong.
  • Citrus fruits
  • Red bell peper
  • Broccoli
  • Garlic
  • Ginger
  • Spinach
  • Yogurt
  • Almonds
  • Sunflower seeds
  • Turmeric
  • Green tea
  • Papaya
  • Kiwi
  • Poultry
  • Shell fish
  • Blue berries
  • Dark chocolate
  • Oily fish
  • Sweet potatoes
  • Kefir

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 20 powerful immune system boosters.

An important note

No supplement will cure or prevent disease.

With the 2021 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:
grapefruit
oranges
clementines
tangerines
lemonslimes
Because your body doesn’t produce or store it, you need daily vitamin C for continued health. The recommended daily amount for most adults is:
75 mg for women
90 mg for men
If you opt for supplements, avoid taking more than 2,000 milligrams (mg) a day.
Also keep in mind that while vitamin C might help you recover from a cold quicker, there’s no evidence yet that it’s effective against the new coronavirus, SARS-CoV-2.
More about citrus fruits

2. RED BELL PEPER

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 mgTrusted Source) as a Florida orange (45 mgTrusted Source). They’re also a rich source of beta carotene.
Besides boosting your immune system, vitamin C may help you maintain healthy skin. Beta carotene, which your body converts into vitamin A, helps keep your eyes and skin healthy.
More about red bell peper

3. BROCCOLI

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.
The key to keeping its power intact is to cook it as little as possible — or better yet, not at all. ResearchTrusted Source has shown that steaming is the best way to keep more nutrients in the food.
More about broccoli

4. GARLIC

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.
Learn more about garlic

5. GINGER

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.
Ginger may also decrease chronic painTrusted Source and might even possess cholesterol-lowering propertiesTrusted Source.
Learn more about ginger

6. SPINACH

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.
Learn more about spinach

7. YOGURT

Look for yogurts that have the phrase “live and active cultures” printed on the label, like Greek yogurt. These cultures may stimulate your immune system to help fight diseases.
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.
Clinical trials are even in the works to study its possible effects on COVID-19.
Learn more about yogurt

8. ALMONDS

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.
Adults only need about 15 mg of vitamin E each day. A half-cup serving of almonds, which is about 46 whole, shelled almonds, provides around 100 percentTrusted Source of the recommended daily amount.
Learn more about almonds

9. SUNFLOWER SEEDS

Sunflower seeds are full of nutrients, including phosphorous, magnesium, and vitamins B-6 and E.
Vitamin E is important in regulating and maintaining immune system function. Other foods with high amounts of vitamin E include avocados and dark leafy greens.
Sunflower seeds are also incredibly high in selenium. Just 1 ounce contains nearly halfTrusted Source 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).
Learn more about sunflower seeds

10. TURMERIC

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.
ResearchTrusted Source 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.
Learn more about turmeric

11. GREEN TEA

Both green and black teas are packed with flavonoids, a type of antioxidant. Where green tea really excels is in its levels of epigallocatechin gallate (EGCG), another powerful antioxidant.
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.
Learn more about green tea

12. PAPAYA

Papaya is another fruit loaded with vitamin C. You can find doubleTrusted Source 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.
Papayas have decent amounts of potassium, magnesium, and folate, all of which are beneficial to your overall health.
Learn more about papaya

13. KIWI

Like papayas, kiwis are naturally full of a ton of essential nutrients, including folate, potassium, vitamin K, and vitamin C.
Vitamin C boosts the white blood cells to fight infection, while kiwi’s other nutrients keep the rest of your body functioning properly.
Learn more about kiwi

14. POULTRY

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.
Poultry, such as chicken and turkey, is high in vitamin B-6. About 3 ounces of light turkey or chicken meat contains nearly one-third of your daily recommended amount of B-6.
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.
Learn more about poultry

15. SHELL FISH

Shellfish isn’t what jumps to mind for many who are trying to boost their immune system, but some types of shellfish are packed with zinc.
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:
1. oysters
2. crab
3. lobster
4. mussels
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 men8 mg for most adult women
Too much zinc can actually inhibit immune system function.
Learn more about shell fish

16. BLUEBERRIES

Blueberries contain a type of flavonoid called anthocyanin, which has antioxidant properties that can help boost a person’s immune system. A 2016 studyTrusted Source noted that flavonoids play an essential role in the respiratory tract’s immune defense system.
Researchers found that people who ate foods rich in flavonoids were less likely to get an upper respiratory tract infection, or common cold, than those who did not.
Learn more about blueberries

17. DARK CHOCOLATE

Dark chocolate contains an antioxidant called theobromineTrusted Source, which may help to boost the immune system by protecting the body’s cells from free radicals.
Free radicals are molecules that the body produces when it breaks down food or comes into contact with pollutants. Free radicals can damage the body’s cells and may contribute to disease.
Despite its potential benefits, dark chocolate is high in calories and saturated fat, so it is important to eat it in moderation.
Learn more about dark chocolate

18. OILY FISH

Salmon, tuna, pilchards, and other oily fish are a rich source of omega-3 fatty acidsTrusted Source.
According to a 2014 report, long-term intake of omega-3 fatty acids may reduce the risk of rheumatoid arthritis (RA).
RA is a chronic autoimmune condition that occurs when the immune system mistakenly attacks a healthy part of the body.
Learn more about oily fish

19. SWEET POTATOES

Sweet potatoes are rich in beta caroteneTrusted Source, a type of antioxidant that gives the skin of the potatoes its orange color.
Beta carotene is a source of vitamin A. It helps to make skin healthy and may even provide some protection against skin damageTrusted Source from ultraviolet (UV) rays.
Learn more about sweet potatoes

20. KEFIR

Kefir is a fermented drink that contains live cultures of bacteria that are beneficial for health.
Initial research suggests that drinking kefir may boost the immune system. According to a 2017 reviewTrusted Source, various studies have shown that regular consumption of kefir can help with:
fighting bacteria
reducing inflammation
increasing antioxidant activity
The majority of the research that supports this was carried out on animals or in a laboratory. Researchers need to perform additional studies to understand how kefir may prevent disease in humans.
Learn more about kefir