5 Surprising Foods that Help Boost Your Immune System

Staying healthy during a hyperactive cold and flu season can be a unique challenge. The foods you eat to boost your immune system can make all the difference. There are plenty of health tips about what you should be eating floating around social media now that Covid-19 has spread around the world, but it can be hard to cut through the haze of information. Plus, some of the most popular health foods are becoming more and more scarce. So, here are some lesser known health foods that can really boost your immune system.


When you think about vitamin C, most people don't reach for the spice rack. Yet, thyme is a powerful source of vitamin C. Half of the daily recommended value of vitamin C can be obtained from just 28 grams (1 oz) of fresh thyme. As a point of comparison, 24 grams of fresh parsley is worth about 30% of your recommended daily vitamin C content.

Thyme is more readily available than other sources of vitamin C. Most people will choose more obvious sources of vitamin C such as oranges, blueberries and grapefruits. Fresh thyme's vitamin content isn't well known by the general public. So, you're likely to find some in the supermarket. Get as much as you can because thyme is also a potent source of copper, vitamin A, iron and manganese.

Culinary Tip: When cooking with thyme to boost immunity, you should consider recipes that won't get overwhelmed by too much thyme aroma and flavor. Roasted chicken with lemon goes well with large amounts of fresh thyme and so do cremini mushrooms.

Sweet Bell Peppers

Chilisand other peppers contain high levels of vitamin C, but most people are leery of embracing the heat. If you aren't accustomed to the burn, then you could suffer from an upset stomach. That won't help you get over a nasty case of the flu or make your quarantine any more bearable.

Go for the sweet bell peppers instead. They come in a variety of shapes and colors - red, green, and yellow are the most common. The color has to do with the age. Green sweet bell peppers are young. The yellow peppers are the most mature. In fact, those are the ones you should eat for better immune health.

The yellow sweet bell peppers have the highest vitamin C content of all the sweet peppers. Taking 75 grams (about half a cup) of sweet yellow bell peppers amounts to 150% of your recommended daily dose. That's easy to achieve when you're cooking a tasty pasta dish.

Did you know: Vitamin C is a natural antihistamine. A study published in the Journal of the American College of Nutrition in 1992 found that taking 2 grams of vitamin C daily leads to lower blood levels of histamine.

Sweet Potatoes

Sweet potatoes are a tuberous root vegetable. They're one of the most versatile potato varieties and lend themselves well to all sorts of culinary applications. They are a popular food for taste, but most people don't think of sweet potatoes as immune system boosters. Sweet potatoes, even when cooked thoroughly, have high levels of vitamin A. Just a single cup of sweet potato provides 200% of your daily recommended intake of vitamin A. It's also a decent source of fiber, protein and potassium.

Sweet potatoes are essential during this time of self-isolation and quarantine. They're hearty and don't spoil quickly. So, you can stock up on sweet potatoes and trust that they won't go bad in your pantry.

Culinary Tip: Baked sweet potatoes provide a warm, soothing meal with a smooth texture. It's also easy to prepare. You can put them in the oven on medium to high heat for 45 minutes and season with just a bit of butter and black pepper. So, if someone is sick and under the weather, then they'll still be able to eat baked sweet potatoes while their immune system battles against a respiratory infection.


Oysters aren't the obvious choice for boosting immune system health, but these shellfish provide a copious number of vitamins and minerals. They're a potent source of vitamin D, antioxidants, copper, vitamin C and zinc.

You don't need to eat a large quantity of oysters to reap their immune system benefits. A single 100 gram serving contains 600% of the RDV of zinc, 300% RDV of vitamin B12, and 80% of your recommended intake of vitamin D. So, as you can see it's important not to overeat oysters. You should always eat them cooked and go for a standard serving of about six oysters.

Did you know: When your body doesn't get enough zinc, you're more susceptible to illnesses, viruses and diseases. Zinc activates T cells in the body and their job is to locate and attack infected cells.


Yogurt is often linked to digestive health, but eating yogurt benefits your immune system, as well. Yogurt has yeast and live bacteria that are beneficial to your body. One of the most important probiotics in yogurt is called lactobacillus acidophilus. It minimizes the amount of lactose in yogurt so that it's easier for the body to digest.

It's all about creating a healthy balance inside your body. The National Cancer Institute points out that yogurt with lactobacillus helps to create an environment in your digestive system that pathogens find inhospitable. In addition to making your gut more acidic, yogurt also forms a protective layer inside your GI tract.

Keeping your digestive system balanced helps your immune system by protecting it against bacterial infections. Now, it's important to note that Covid-19 is a viral infection. However, the probiotics in yogurt can take some of the strain off your immune system.

Health Tip: Not all yogurts on the dairy aisle are the same. Avoid sugary yogurts that add fruity syrups. Instead, choose a yogurt with few ingredients and be sure to look for live and active cultures. That means it has the right number of probiotics for health benefits.  

Summing it Up

Maintaining a strong and healthy immune system has never been more important. Ironically, there are brand new challenges that people face when trying to source their nutrition. Supermarkets face dwindling supplies. Citrus fruits and certain vegetables are flying off the shelves. This presents a unique opportunity to discover surprisingly nutritious foods like thyme, sweet peppers and oysters. The nutritional value of these foods are remarkably high, but their popularity is relatively low. So, this is the perfect time to boost your immune system and expand your palette.