Foods to Boost Your Immune System

Does an apple a day really keep the doctor away? Unfortunately, the answer is a little more complicated. For years, researchers have been trying to understand the complex link between the food we eat and how it affects our immune system. Most researchers have come to the consensus that “a person’s overall nutrition status, state of nourishment, and pattern of intake (comprised of foods, nutrients, and non-nutritive bioactive compounds) impact the functioning of the immune system.”

However, because of the complexity of our immune systems, different foods affect the immune system in different ways. Our immune system is comprised of many levels, including physical barriers, the microbiome, the innate immune system, and the adaptive immune system. Each faction of the immune system reacts uniquely to micronutrients, but they all share one commonality- they require micronutrients to function.

The Immune System Explained

The immune system is one of the most complex and intricate systems in the human body. It consists of a network of stages and pathways that work to protect us from harmful microbes and diseases. Our immune system can recognize foreign bacteria, viruses, and parasites and take immediate action against them.

The immune system can be separated into two categories; innate immunity and adaptive or acquired immunity.

• Innate immunity is our first line of defense against pathogens as they attempt to enter our bodies. This protection is given through protective barriers. The innate immune system includes the skin, mucus that traps pathogens, stomach acid that destroys pathogens, enzymes in our sweat and tears that create anti-bacterial compounds, and immune cells that attack all foreign cells entering our bodies.

• Adaptive or acquired immunity is the more complex of the two. Adaptive immunity is the system that learns to recognize a pathogen. The organs in our body like the spleen, thymus, bone marrow, and lymph nodes assist in this process. These organs create and multiply antibodies when exposed to a foreign substance. They also play a key role in remembering the foreign substance to be able to quickly identify and attack it if it re-enters the body in the future.

The Role of Micronutrients

Obviously, many, many different cells work in the two separate categories of the immune system, and these cells require different types of micronutrients in order to function efficiently. Through different stages of our body’s immune response, different micronutrients are needed. This wide array of required micronutrients make it difficult for one superfood to enhance our entire immune system. However, some micronutrients have been identified as being critical in the function and growth of immune cells. These micronutrients are as follows:

• Vitamin C

• Vitamin D

• Zinc

• Selenium

• Iron

• Protein

The only way to truly eat for your immune system is to have a healthy and diverse diet in order to fulfill all of these nutrient requirements. These nutrients offer immuno-protection because of their antioxidant capacity. Most of these nutrients can be found in fruits, vegetables, and meat. Unfortunately, the Western diet so many of us eat lack these essential requirements.

With high levels of refined sugars, processed foods, salt, and red meats, the Western diet can not only hurt your general health but can also cause damage to your ability to fight off foreign pathogens. The Western diet can promote the destruction of healthy intestinal microorganisms, which results in gut inflammation. Inflammation of any kind, especially that of the gut, is associated with suppressed immune system function. Eating to ensure a healthy gut and microbiome can work wonders to strengthen your immune system.

The Role of the Microbiome

The microbiome consists of the trillions of microorganisms that live mostly in our intestines. Research has also demonstrated that the microbiome plays a major role in the effectiveness of our immune system and the production of antimicrobial proteins. Your diet plays a major role in the types of microbes living in your intestines. A high-fiber, plant-rich diet with lots of fruits, vegetables, whole grains, and legumes supports a healthy microbiome- therefore supporting the growth of immune cells.

Eating a balance of probiotic and prebiotic foods is especially helpful in creating promoting gut health. Probiotics are foods that contain helpful bacteria. Such foods include kefir, yogurt with live cultures, fermented vegetables, sauerkraut, tempeh, kombucha tea, kimchi, and miso. Prebiotic foods consist of high levels of fiber and oligosaccharides that feed colonies of bacteria in the gut. Prebiotic foods consist of garlic, onions, leeks, artichokes, dandelion greens, bananas, and seaweed.

In all, the general consensus around how to eat to support a healthy immune system is to eat a balanced diet with whole fruits, vegetables, lean proteins, whole grains, and lots of water. The low carbohydrate Mediterranean Diet is one great example that encompasses many of these foods. There are also many supplemental options to increase your micronutrient levels.

Incorporating Micronutrients into Your Diet

Adding these integral micronutrients into your diet is actually easier than you would probably think! They are present in many different types of foods. Further, there is a lot of overlap in what foods contain what kinds of micronutrients. Thus, making simple additions to your diet can actually cause a big impact!

Vitamin C

• citrus fruit (oranges and lemons)

• peppers

• strawberries

• broccoli

• blackcurrants

• brussels sprouts

Vitamin D

• fatty fish (tuna, mackerel, salmon)

• beef liver

• cheese

• egg yolks

Zinc

• oysters

• red meat

• beans

• nuts

• dairy products

Selenium

• brazil nuts

• tuna

• halibut

• shrimp

• turkey

Iron

• red meat, pork, and poultry

• seafood

• beans

• spinach

• peas

Protein

• lean meats

• poultry

• fish and seafood

• dairy products

• black beans

For more information on how to eat for your immune system and which micronutrients you need, email our office at thejohnsoncenter@gmail.com or call 276-235-3205.

The Johnson Center for Health services patients in-person in our Blacksburg and Virginia Beach locations. We also offer telemedicine for residents of Virginia and North Carolina!