1. Dark Chocolate

Believe it or not, dark chocolate is a good booster for your immune system. This is because it contains theobromine, an antioxidant that is known to help shield the body's cells from free radicals.

These radicals are by-products of digestion, and they actively pollute the human body system making it more vulnerable to invading pathogens.

2. Sweet Potatoes

These sweet tubers are a potent source of beta carotene, another important antioxidant which is a good source of vitamin A.

So, it doesn't only contribute to strengthening your immune system; it gives you healthy skin and protects you from damaging ultraviolet rays. 

3. Broccoli

It is not surprising to find this common vegetable on this list. When eaten in adequate amounts, broccoli is a rich source of vitamin C. 

Even better, it also contains strong antioxidants like sulforaphane that are known to boost the human immune system.

4. Spinach

There is no end to the importance of eating vegetables. Spinach, a common food staple, is an excellent source of numerous essential nutrients and antioxidants, like vitamin C, vitamin E, flavonoids and carotenoids which boost the immune system.

5. Blueberries

Blueberries contain antioxidants that may help boost the immune system. According to experts, they have a flavonoid called anthocyanin that can help boost a person's immune system.

From past scientific studies, consuming flavonoids can help you protect your respiratory tract by strengthening its immune system.

6. Green Tea

Green tea can be a good substitute for your daily cup of coffee. This is not just because it is delicious; it is a potent booster for your immune system as it also contains flavonoids.

7. Almonds

As small as a handful of almonds is a very healthy snack that will benefit your immune system. Almonds are enriched with vitamin E, manganese, magnesium, and digestive fibre.

8. Oily fish

This includes salmon, tuna, pilchards, and many more others which are an excellent way to dose up on omega-3 fatty acids. A 2014 research also reports that constantly consuming oily fishes can help prevent rheumatoid arthritis, which is a disease caused by the immune system abnormally attacking a healthy part of the body.

9. Turmeric

This famous spice is a good source of curcumin which helps boost the immune system. The curcumin is a well-known antioxidant that additionally has anti-inflammatory properties.

10. Ginger

Last but not least is ginger which is commonly used as a spice in meals and teas. According to experts, ginger has anti-inflammatory and antioxidative properties and is likely to offer health benefits.

On a final note, it is essential to note that daily consumption of fruits can help boost your immune system as they contain numerous vitamins and antioxidants.