Immune Boosters: Do They Work and Which Ones Help?

What Are Immune Boosters?

Immune system boosters are a compelling concept: Take this drink and suddenly your immune system is optimally supported and functioning at its best. The reality of immune health is actually more empowering—it's about maintaining a healthy lifestyle that supports overall immune function over the long run. While that's not quite as exciting or easy, immune support supplements can play a role in supporting your body's immune defenses. In this guide, we break down why we need to reframe the idea of "boosting" your immune system, and how best to support immune system balance.

"Immune-boosting" products have become a popular wellness trend, coming in many forms (powders, bottled drinks, capsules, droppers) and usually containing just one or a few vitamins, minerals, or herbal ingredients. They're typically sold on a single idea: that your immune system isn't keeping up on its own and needs an outside push to work harder than it naturally would.

But that's not how immune health works. A healthy immune system constantly produces and renews the immune cells it needs, such as lymphocytes, through a tightly balanced process. A healthy immune system does not run at maximum. It can respond to a challenge when needed, then settle back to baseline once the job is done.

The real goal is sustaining immune system balance (homeostasis) over time. A healthy immune system can respond to challenges when needed and then return to baseline once the response is complete. Maintaining this balance is shaped mostly by getting sufficient sleep, exercising regularly, managing stress, and eating a balanced diet.^1-4 Supplements can support this routine by helping to fill common nutrient gaps, including vitamins and minerals that are required to support normal immune function.

Food and Vitamins for Immune Health

Eating a variety of fruits, vegetables, whole grains, beans, and nuts provides a whole host of benefits: essential nutrients, fiber, plant compounds called phytonutrients, and cofactors ("helper molecules") that enhance the effectiveness of vitamins and minerals.

The food we eat also impacts our gut microbiome, the hub for much of the immune system. A diet high in processed foods, saturated fats, and refined sugar can disrupt the balance of this ecosystem.⁴ Instead, focus on a diet that combines fiber, prebiotic foods (onions, leeks) that feed gut bacteria, as well as probiotic foods (yogurt, kefir) that promote "good" bacteria.

Check out our blog post on the best foods for an immune system boost.

Benefits of Immune Support Supplements

Micronutrients (vitamins and minerals) are the fuel that allows our cells to function properly. Each micronutrient has a specific job, enabling the body to produce the enzymes, hormones, and proteins that are essential to complex immune processes. And yet, nutrient gaps are surprisingly common, even among generally healthy people. Studies show that a significant number of Americans fall short of recommended intake levels for many immune-supporting micronutrients, particularly vitamins D and E.⁵

Supplements can be a convenient way to fill common nutrient gaps, helping ensure your immune system has the fuel it needs to function properly.

Top Immune Support Ingredients

Which micronutrients are the most important to immune function? Be sure to get adequate amounts of:

Vitamin C

Vitamin C supports leukocytes (white blood cells) in mounting a rapid response. It plays a role in the "respiratory burst," a natural process where white blood cells use oxygen to help support the body's cellular defense processes. As an antioxidant, it also helps protect these cells from oxidative stress generated during normal immune activity.⁶

Good sources include: citrus, strawberries, bell peppers, and tomatoes.

Vitamin D

Vitamin D (specifically D3) supports nearly every cell in the immune system. In particular, it supports the production of compounds involved in the body's natural defenses.⁷

Good sources include: sunlight, fatty fish (salmon), egg yolks, and fortified dairy.

Zinc

Zinc plays an important role in the development and function of many immune cells. It also supports normal immune cell signaling, including processes that help T-cells respond to challenges.⁸

Good sources include: oysters, seeds, and whole grains.

Selenium

Selenium supports antioxidant enzyme production, which helps maintain cellular health.⁹

Good sources include: Brazil nuts, seafood (tuna, sardines, halibut), eggs, sunflower seeds, and whole-wheat bread.

For a deeper dive, read Vitamins for Immune Health.

How to Choose the Right Immune Supplement

Choosing the right supplement starts with understanding your body's needs and how different nutrients work together to support natural immune balance.

Single-ingredient or foundational nutrition?

If you're looking to support immune function with supplements, there are a few different approaches you can take, from targeting specific nutrients to covering a wide variety of ingredients with a foundational nutrition approach. The first strategy makes sense if you have particular immune-support nutrients you want to focus on and only wish to take one or more single- or multi-ingredient supplements. There are also instances where it's beneficial to take an ingredient in a specific form. For example, we offer vitamin D as an oil with vitamin K2 for better absorption.

If you want a simpler way to cover common nutrient gaps and support overall health, a foundational nutrition supplement like AG1 may be the way to go. In addition to key vitamins and minerals, AG1 provides stress adaptogens (rhodiola, ashwagandha), pre- and probiotics for gut health, and functional mushroom complexes that provide phytonutrients—all of which are being studied for their roles in supporting immune function.^10-12

Bioavailability

Bioavailability—how absorbable a vitamin or mineral is—can vary widely depending on the form it's in. For example, zinc citrate and picolinate are more bioavailable than some other forms, like zinc oxide.^13,14 Look for supplements that are formulated based on the latest research.

Third-party certification

When shopping around for immune support supplements, look for a third-party seal on the label. These independent certifications let you know that the supplement contains high-quality ingredients. For example, NSF Certified for Sport® is one of the strictest quality and safety certifications for supplements. NSF inspects manufacturing facilities, monitors ingredients for toxicology, and makes sure that label claims are accurate. It also certifies that the product is free from over 280 substances banned by major athletic organizations. AG1 is proud to be NSF Certified for Sport®.

For a deeper dive, read our guide to evaluating immune support supplements.

Drinking AG1 for Immune Support

Support your immune function by supporting your body's response to environmental stress, replenishing antioxidants, and supporting gut health. To help fill gaps and support your health journey, get started with AG1 today.*

Try AG1

References:

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