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What You Need to Know About Your Diet and Immune Function

Oh no, not again. You feel your throat getting scratchy, and you're congested. You think, "How can I be sick... AGAIN?"

If you are the type of person that seems to get sick every month, or even several bad colds a year, you'll want to look into how your diet and immune function are connected.

The foods you eat play a HUGE role in how your body can function. Your diet gives your body its main supply of vitamins and minerals needed to carry out optimal processes.

But, if your diet isn't so healthy, it could inhibit you from experiencing optimal immune health and cause you to get sick more frequently.

So, let's chat about how your immune system functions, what foods you should avoid, and what foods you should have stocked up on in your home!

How Does the Immune System Work?

Your immune response is made up of multiple organs and cells that help fight off viruses, bacteria, and other foreign invaders (skin, blood cells, lymph nodes, antibodies, spleen, & mucous membranes).

The immune response should have a healthy balance between being ready to fight invaders and not being overactive, causing chronic inflammation.

Your immune response to pathogens should be effective at addressing the issue AND rapid to avoid any underlying inflammation. Because certain minerals and vitamins are needed for this process, nutrients (from your diet) are vital to enhancing your immune response.

For example, arginine (an amino acid) is necessary for the production of nitric oxide, which is a vital regulator of the immune response.

Vitamin A and zinc regulate cell division, which is needed for a proliferative response within the immune system to help spread the immune response.

This is why your diet can be a significant contributor to boost a healthy immune function.

What Happens When You Have an Impaired Immune Response?

  • You Get Sick Frequently

  • Your Wounds Heal Slowly

  • Constant Stomach Issues (70% of your immune system is located in your gut!)

  • Frequent Infections

  • Always Feeling Fatigued

If you are experiencing any of these, it could be a sign that your immune function is not looking too good!

What Can Weaken your Immune Response?

High GI Diet

A diet of high glycemic foods can wreak havoc on your immune function. Foods low on the glycemic index (GI) scale tend to release glucose slowly and steadily. While foods high on the glycemic index release glucose more rapidly.

What Foods Are High on the Glycemic Index?

  • White bread

  • Potatoes

  • White rice

  • Candies

  • Sweets (cookies, ice cream, etc)

When you consume high GI foods, your insulin spikes, and glucagon levels drop. When your blood sugar is constantly spiking, it increases your risk for type 2 diabetes and heart disease AND weakens your immune function.

How does it weaken your immune function?

When you have high blood sugar, even if it’s temporarily, it decreases the activity of white blood cells, reducing your body’s ability to fight off infection. If you eat a meal that spikes your blood sugar levels, your immune system could be weakened for 4-5 hours!

Did you also know that vitamin C is essential for white blood cells to function optimally? Since sugar and vitamin C have a very similar chemical structure, when you consume sugar it directly competes with vitamin C and as a result, less vitamin C can enter into your white blood cells.

Swap Out High GI Foods for Low GI Foods Like:

  • Green vegetables

  • Most fruits

  • Kidney beans

  • Chickpeas

  • Lentils

  • Bran breakfast cereals

Diet Lacking in Color Variety

Did you know that the color of your food can tell you which types of phytonutrients you are consuming? This is important because a variety of different phytonutrients are needed to support your body and immune system!

If your plate looks pretty dull, the nutrient profile is most likely dull as well! Brighten your plate up a bit, to get ample amounts of a variety of nutrients.

Want to know the benefits of each food color?

Red: contain carotenoid lycopene, a potent scavenger of gene-damaging free radicals (strawberries, red peppers, tomatoes)

Yellow & Orange: contain high amounts of vitamin C and flavonoids, which have antioxidant properties and reduce inflammation (carrots, sweet potatoes, peppers).

Green: contain cancer-blocking chemicals like sulforaphane, isocyanate, and indoles, which inhibit the action of carcinogens

Purple and Blue: contain powerful antioxidants called anthocyanins which are believed to delay cellular aging (blueberries, blackberries, eggplant, lavender, purple cabbage).

White and Brown: contains allicin, which has anti-tumor properties (onions, cauliflower, garlic, leeks, mushroom)

These are all essential in the optimal functioning of your immune response on a cellular level. You want to ensure your body is equipped with the necessary resources and tools to fight disease cells and inflammation, so chronic diseases and a weakened immune response don’t manifest.

Processed Foods

Processed foods cause havoc on your body for a handful of reasons. They are more likely to contain unhealthy preservatives, toxins (like pesticides), additives (like food dyes), and high levels of excess sugars- YUCK!

These can be pro-inflammatory and can even be seen as foreign invaders to your body. When you constantly eat processed foods multiple times a day, you’re putting unnecessary pressure on your immune system.

Food Sensitivities

Underlying food sensitivities can greatly impact your immune function. Food sensitivities can damage your gut lining and allow those food molecules to get into your bloodstream. They are seen as foreign invaders and cause your immune system to ramp up.

I run a food sensitivity test with all my clients to be sure to eliminate any immune-weakening contributors!

What to Eat to Enhance Immune Function

  • Make your meals primarily organic whole foods

  • Make your plate as colorful as possible

  • Avoid processed foods (many packaged foods, frozen ready-to-go meals, granola bars are not as healthy as they are marketed to be!)

  • Follow a Mediterranean diet (this is the most studied and effective anti-inflammatory diet)

  • Focus on consuming a varied diet, which reduces the chance your body will start reacting to any particular food

  • Pair foods together to lower the overall glycemic load of your meals (Check out the Low Gly-Cal app to see how pairing foods can impact the glycemic load).

Optimize Your Diet and Immune Function with an Expert

If you want to prioritize your immune health, make an appointment with me. I'm Jessica Meyers, a Functional Medicine and Herbal Expert.

Together, we can investigate the impact of your diet and immune function and uncover any other underlying causes that may be keeping you from feeling healthy all year long!

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