Vitamins for Immune Health: Which Nutrients Matter Most for Immune Support

Understanding immune health

The immune system is a complex network of organs, tissues, cells, and biochemical messengers, and several vitamins and minerals make it possible for this network to function properly. These nutrients act as antioxidants, protecting cells from free radicals and environmental stress.

• They can be signaling molecules that tell immune cells where to go.
• They can be cofactors, which are vital helper molecules that join enzymes to activate cells.
• Together with other factors, these essential nutrients help maintain a balanced, resilient immune system.

The best way to acquire these vitamins and minerals is through a varied diet of whole foods. However, consistently meeting the daily recommended amounts of these nutrients can be difficult. Beyond our busy lifestyles, studies show that the nutrient density of whole foods is also declining due to environmental factors, soil depletion, and modern farming practices.^1,2
According to the , a substantial number of Americans fall below the Estimated Average Requirement (EAR) for several key vitamins. Vitamins D and E are the most common shortfalls—95% and 84% of adults have an estimated intake below recommended levels. Additionally, almost half of those surveyed weren’t getting recommended levels of vitamins A and C. In the case of nutrient gaps, to a healthy diet.

Vitamins for immune support

Your body absorbs important nutrients from your food and supplements to maintain normal immune function. Here are some of the most important vitamins for immune support.

Fat-soluble vitamins

Fat-soluble vitamins dissolve in fats and oils, allowing them to be absorbed alongside dietary fats. They are stored in the body’s liver and fatty tissues.

Vitamin A
The skin and the mucous membranes of the lungs, nose, and other areas are the body’s first line of defense. Vitamin A plays a role in maintaining those barriers, while also supporting the differentiation of immune cells—the process in which immature cells become specialized for a specific job.³

Good sources: Carrots, oranges, sweet potatoes, dark leafy greens, liver, and dairy.⁵

Vitamin D
Vitamin D supports first responder immune cells’ ability to multiply. It also plays a role in keeping the immune system in balance.⁶: Primarily sunlight, but can be obtained from oily fish or fortified foods.

How vitamins support your immune system

Beyond focusing on which vitamins help immune system function, you should also be aware of the amount and the form of the nutrients you’re getting.

For example, iron and zinc tend to have greater bioavailability if ingested from animal rather than plant sources.¹⁷ While absorption depends on individual factors, vegetarians and vegans are more likely to fall short of the recommended intake of these minerals and may be good candidates for supplementation.¹⁸ If using supplements, it’s important to know that these nutrients also come in different forms with varying degrees of bioavailability.

Absorption can also be affected by other nutrients. Fat-soluble vitamins like A and D require dietary fats for optimal absorption, making it important to pair them with healthy fats from oils, avocados, fish, and nuts.¹⁹ Certain other nutrients can compete for absorption. For example, high-dose supplementation of copper and zinc may inhibit iron uptake, while iron can inhibit copper absorption. These nutrients should be taken separately if possible.

Tips for maintaining a healthy immune system

In addition to paying attention to minerals and vitamins for immune health, consider adding pro- and prebiotics to your diet. Probiotics are typically found in fermented foods like sauerkraut, yogurt, and cottage cheese, as well as drinks like kefir and kombucha (just make sure to buy the kind with “live cultures”). Probiotics introduce helpful bacteria into your gut, the center of much immune activity. Prebiotics are plant fibers that gut bacteria ferment, essentially feeding the microbiome and supporting immune function.²¹

Combining a nutrient-rich diet of whole foods, prebiotics, and probiotics with regular exercise, adequate sleep, and stress management is the formula for a healthy immune system. At the same time, avoid the trappings of the Western Diet. Saturated fats, refined sugar, and ultraprocessed foods have been linked to changes in balance.While whole foods are the best source of vitamins for immune system support, supplements can help fill nutrient gaps.

How foundational nutrition supplements work

Instead of relying on many individual supplements, keeping track of dosages, and maximizing bioavailability, many people turn to a foundational nutrition supplement for more convenient support.

AG1 combines over 75 vitamins, minerals, and whole-food-sourced ingredients to help fill common nutrient gaps and support whole-body health, including immune health. With prebiotics and probiotics that promote a healthy gut and support immune defense, AG1 Next Gen is a clinically studied formula that helps fill common nutrient gaps in one daily scoop.*

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References:

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2. Myers SS, Zanobetti A, Kloog I, et al. Increasing CO2 threatens human nutrition. Nature. 2014;510(7503):139-142. doi:10.1038/nature13179
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9. Budiarto R, Mubarok S, Nursuhud N, Rahmat BPN. Citrus is a Multivitamin Treasure Trove: A Review. J Trop Crop Sci. 2023;10(1):57-70. doi:10.29244/jtcs.10.1.57-70
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