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Foods That Weaken Immune System {Episode 228}

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Foods That Weaken Immune System {Episode 228}

We’ve talked a ton about what can we do to build our immune system, but let’s turn the conversation around and talk about what foods weaken the immune system. Because we can build and support our immune system, but if we’re constantly doing things that bring DOWN our immune system – we’re going to be fighting an uphill battle.

What Foods Weaken The Immune System?

Sugar Weakens Immune System

This isn’t news to most of you. I’ve previously talked about how sugar and vitamin C use the same cell receptor to get inside the cell + when we’re flooding our bodies with sugar, we don’t allow vitamin C (one of the biggest immune supporters) to get inside the cell. Leaving us full of sugar and deficient in vitamin C.

Sugar consumption can produce inflammation and it can affect the way that your white blood cells target infection. Sugar also impacts our gut microbiome by throwing off the balance between good and bad bacteria – favoring more bad bacteria and yeast overgrowth. Our microbiome plays a bigger role than the immediate gut immune response, but the whole body immune response. If our microbiome is out of wack, other systematic diseases, like cardiovascular disease, allergies, autoimmune conditions, are at an increased risk.

This is why SODA is a big food that weakens the immune system due to the sugar content (and the lack of nutrients). One soda can contain between 5-8 tablespoons of sugar, which people can demolish one or two cans per day!

Processed Food Weakens Immune System

Sugar is a big part of the processed food, but more than anything, processed food takes place of nutrient-dense foods when we consume them. During a time where you need to support your immune system immensely, we need to try and take every hunger pang to FUEL our body with nutrients that support our body versus a food that is nutrient void.

Nutrient void food is empty calories that do NOT serve your body. By the end of the day if you look at what you’ve eaten, you may have gotten minimal nutrients. In the Standard American Diet, this isn’t uncommon. In the processed food category, you’ll find refined carbohydrates. These refined carbohydrates (breads, crackers, pasta , etc.) increase blood sugars and insulin response and increase risk of diabetes. Diabetics have been studied to have lower amounts of Natural Killer Cells. Natural killer cells are a white blood cell and are part of the innate immune response toward viruses and even tumors.


  1. Get access to a Thrival-approved grocery guide
  2. Whole-food recipes to get you started
  3. How-to starting guide to balancing your hormones

    Alcohol Weakens Immune System

    Alcohol is another source of sugar to spike our blood sugars and it also suppresses our white blood cells, which are vital during infection. This definitely comes as a concern if alcohol usage plays a regular part of your routine every day. In chronic use of alcohol, immune cell markers that were increased are…

    • TNF-alpha
    • IL-10
    • IL-6
    • IgA
    • IgM

    Acute use of alcohol has not shown these effects with the immune system probably due to the antioxidants, but I’m a proponent for getting those antioxidants and health benefits elsewhere because it doesn’t change how alcohol can be taxing on the liver to metabolize it.

    If you get rid of these foods, you’re one step ahead of most people to being on your way to optimal health!

    Getting your body’s immune system functioning optimally is so important! If you’re ready to get a dietitian/nutritionist to help you with this, head over to our Work With Us page and fill out the form to request your free appointment..

    We do micronutrient testing + food sensitivity testing that can be beneficial to help you learn what nutrients you need to replete + what foods to avoid to minimize inflammation (let’s get rid of that chronic inflammation ya’ll!).

    Connect with us + join the fun over on Instagram + Facebook if you haven’t already @nuvitruwellness!

    Stop eating foods that weaken your immune system! Stay healthy, friends!

    Lahana Vigliano, CCN

    Avatar for Lahana Vigliano
    Lahana Vigliano

    Lahana Vigliano is a Certified Clinical Nutritionist and CEO of Nuvitru Wellness. She has her Bachelor's Degree in Nutrition Science and Masters Degree in Nutrition Science and Functional Medicine. She is currently pursuing her doctorate degree in Clinical Nutrition. Lahana and her team help support women who struggle with weight loss, hormonal imbalances, digestive issues, chronic fatigue, and many other lingering issues that leaves women not feeling their best. She uses food as medicine, as well as herbs and supplements when needed, to support her clients. She looks at the whole body holistically making sure women are understanding how nutrition, sleep, stress, and their environment impact their health. Connect with her on Facebook + Instagram (@nuvitruwellness).