In This ArticleView AllIn This Article1. Refined Grains2. Alcohol3. Sugar-Sweetened Beverages4. Fried Foods5. Red Meat and Processed Meats6. Caffeinated Beverages7. Salty FoodsFAQs
In This ArticleView All
View All
In This Article
Refined Grains
Alcohol
Sugar-Sweetened Beverages
Fried Foods
Red Meat and Processed Meats
Caffeinated Beverages
Salty Foods
FAQs
Like a cape-clad superhero, your immune system constantly monitors villainous threats, like viruses or bacteria, and jumps into action when you come down with an illness. After the COVID-19 pandemic, keeping your immune system in fighting shape for the next virus may be top of mind.
While no specific food or supplement can guarantee that you’ll never get sick, your overall diet can play an important role in supporting the work your immune system does to ward off unwanted infections.
Eating a diet that is high in fiber and healthy fats and provides sufficient amounts ofkey nutrients, like vitamins A, E, C, D, zinc and iron, can optimally support your immune system. However, a diet lacking these nutrients and high in added sugars and saturated fat could weaken your immune system.
To give your immune system all the support it needs to keep you from getting sick, here are seven foods you should limit.
Healthy Immunity Meal Plan
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Since the majority of your immune cells are found within the lymphoid tissue lining the gut, it is important to limitrefined carbohydrates, which generally are higher in sugar and stripped of the fiber that allows a healthy gut to thrive.
According to a 2022 research review published inAllergy, dietary fiber supports the immune system in a couple of different ways.
While light to moderate alcohol intake may have some health benefits, excessive alcohol intake offers potential negative consequences—including to your gut, which plays a vital role in immunity.
A 2021 review inToxicology Reportsnoted that alcohol couldaffect the diversity of the healthy bacteria in your gutand contribute to a less functional gut barrier—meaning pathogens can sneak past it. Excess alcohol intake can also inhibit your immune system’s ability to create the antibodies you need to ward off foreign invaders, like the flu virus.
Alcohol also disruptssleep, which is essential for the immune systemto be in tip-top shape. If you like to have the occasional drink, do so in moderation—two standard drinks or less per day for men and one or less per day for women, per theCenters for Disease Control and Prevention (CDC).
We know that too much added sugar isn’t good for you. Excessive sugar intake, particularly through sugar-sweetened beverages, may negatively affect the body and contribute to a weakened immune system.
According to a 2022 review inHuman Immunology, excess fructose (a type of sugar) intake alters the makeup of your gut microbiota so that the beneficial strains of bacteria have more trouble thriving. High blood sugar levels can also alter the gut’s permeability, contributing tochronic inflammation. Although inflammation is a normal step in the body’s innate immune response, chronic inflammation can leave your immune system too overworked and weak to ward off new infections.
What Happens to Your Body When You Cut Out Sugar
Fried foods are higher in advanced glycation end products (AGEs). These compounds naturally occur during cooking, especially at high temperatures like frying. Research, such as a 2020 article inNutrients, found that AGEs may be associated with a less optimal gut microbiome, increased inflammation and a weaker intestinal barrier—which can all negatively affect your immune system.
A little TMAO is nothing to worry about, but higher levels of TMAO are often associated with an unhealthy community of gut bacteria, chronic inflammation and a weakened immune system, as noted in a 2020 review inFrontiers in Immunology.
A large 2023 study published inRespiratory Researchfound a link between adding salt to foods and sleep apnea, a condition with which there are interruptions in breathing while sleeping. Per theCDC, sleep apnea results in a lack of quality sleep—and as we’ve already seen, lack of sleep is linked with a weaker immune system.
Most people generally eat a lotmore salt than is recommended. According to theFDA, Americans consume about 3,400 milligrams of sodium per day. Yet, the2020-2025 Dietary Guidelines for Americansrecommend that adults limit sodium intake to less than 2,300 mg daily—or about 1 teaspoon of table salt.
To reduce your overall salt intake, consume fewer foods that are high in sodium—like fast food, salty snacks, processed meats and canned goods. And limit how often you’re reaching for the salt shaker. Instead, swap the salt out for herbs and spices to ramp up the flavor in your dishes.
The Bottom Line
Frequently Asked QuestionsA 2022 review inNutrientssuggests following nutritious diets—like the Mediterranean diet, which includes foods high in fiber,omega-3 fatty acids, vitamins A, C, D and E, and zinc—can best support a healthy immune system.We also know that staying hydrated andeating enough protein is important. Some foods to incorporate into your diet more often to support your immune system are whole grains, fruits and vegetables, nuts and seeds, legumes, lean meats and fatty fish.A diet high in ultra-processed foods, added sugar, sodium and saturated fat may increase chronic inflammation and reduce your immune function. This, in turn, increases your risk of chronic health conditions such as type 2 diabetes and heart disease.Chronic undernutrition,dehydrationand excess alcohol consumption can weaken your immune system, making you more susceptible to disease.Lifestyle factors like stressand lack of sleep also impact your immune system. So when cold and flu season comes around, make sure that you aren’t only eating a balanced diet but prioritizing sleep and strategies for reducing stress.
Frequently Asked Questions
A 2022 review inNutrientssuggests following nutritious diets—like the Mediterranean diet, which includes foods high in fiber,omega-3 fatty acids, vitamins A, C, D and E, and zinc—can best support a healthy immune system.We also know that staying hydrated andeating enough protein is important. Some foods to incorporate into your diet more often to support your immune system are whole grains, fruits and vegetables, nuts and seeds, legumes, lean meats and fatty fish.
A 2022 review inNutrientssuggests following nutritious diets—like the Mediterranean diet, which includes foods high in fiber,omega-3 fatty acids, vitamins A, C, D and E, and zinc—can best support a healthy immune system.
We also know that staying hydrated andeating enough protein is important. Some foods to incorporate into your diet more often to support your immune system are whole grains, fruits and vegetables, nuts and seeds, legumes, lean meats and fatty fish.
A diet high in ultra-processed foods, added sugar, sodium and saturated fat may increase chronic inflammation and reduce your immune function. This, in turn, increases your risk of chronic health conditions such as type 2 diabetes and heart disease.
Chronic undernutrition,dehydrationand excess alcohol consumption can weaken your immune system, making you more susceptible to disease.Lifestyle factors like stressand lack of sleep also impact your immune system. So when cold and flu season comes around, make sure that you aren’t only eating a balanced diet but prioritizing sleep and strategies for reducing stress.
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