We already know vitamins and minerals are key to our overall health and wellbeing. But of those nutrients, what vitamins are good to help maintain a healthy immune system? And are we actually consuming enough of them to give our immune system the support it needs? Our experts took a look at the data in a study published last year, and it turns out the US population isn’t consuming nearly enough of these 5 key immune support nutrients. †
Researchers at Pharmavite LLC, the makers of Nature Made® vitamins, analyzed the data on dietary intake of 26,000 adults from the US National Health and Examination Survey (NHANES) between 2005–2016.
Adults in the United States aren’t meeting the minimum requirements of the immune health nutrients vitamin A, vitamin C, vitamin D, vitamin E, and zinc. †
There are five key nutrients for immune health: vitamin A, vitamin C, vitamin D, vitamin E, and zinc (which is technically a mineral). These nutrients are essential to the immune system’s ability to function. But the data shows most of us aren’t getting enough of them. †
The NHANES study, which represents the adult U.S. population, found that:1
45% don’t consume enough vitamin A
46% don’t consume enough vitamin C
95% don’t consume enough vitamin D
84% don’t consume enough vitamin E
15% don’t consume enough zinc
Nutrient gaps like these can cause a host of problems on their own and often lead to a deficiency, but sometimes their symptoms can be so subtle they’re easily overlooked or dismissed as something else. So, when the US population shows big nutrient gaps for five key immune support nutrients, it may help to remind ourselves just why these vitamins and minerals are so important to our immune health, and how to make sure we’re getting enough of them. †
What does vitamin A do for the immune system?
Vitamin A is best known for its role in healthy eye function, but it’s also a key player in supporting the immune system too. Vitamin A supports your skin, airway lining, digestive tract, and even urinary tract, which all serve as a barrier in the body’s first line of defense.2 It also helps regulate the function of immune cells. †
What the study found about vitamin A
The study showed 45% of Americans fell short in vitamin A. The recommended dietary allowance (RDA) for vitamin A is 700–900 μg/day,3 but the usual intake for vitamin A was only 639 μg.
What does vitamin C do for the immune system?
You may have heard that the immune system has two primary lines of defense: innate and adaptive. Vitamin C plays key roles in both of these.1 Vitamin C helps support the epithelial layer in the skin, which functions as a barrier for the body. Vitamin C plays a vital role in immune health by working with other antioxidants to neutralize free radicals, which helps keep white blood cells healthy.1†
The study found 46% of the population fell short in vitamin C. The RDA for vitamin C is 75–90 mg/day,3 however, optimal daily intake is at least 200 mg/day, the amount needed to reach optimal cell and tissue levels to neutralize free radicals effectively.4 But the study found the usual intake was well below this, at 83 mg.
While 83 mg may hit the RDA, it’s far below the optimal amount of vitamin C. And when it comes to our health, shouldn’t we all be striving for more than the bare minimum?
What does vitamin D do for the immune system?
Vitamin D also plays a role in both the adaptive and innate immune responses. Vitamin D receptors are found throughout the body, including immune cells. Vitamin D’s key roles are coordinating the activities of the immune system and balancing the immune response.5†
What the study found about vitamin D
The study found 95% of the population fell short on vitamin D intake. The RDA for vitamin D for bone health is 600–800 IU (15–20 μg)/day.6 For overall health, the Endocrine Society recommends 1500–2000 IU (38–50 μg).7 However, the daily intake of vitamin D was a meager 188 IU (4.7 µg).
Vitamin E’s main role in every step of the immune system is as a fat-soluble antioxidant that protects the immune cell membranes from free radical attack. Vitamin E works together with Vitamin C as the antioxidant tag team to keep immune cells healthy and ready for action.8†
What the study found about vitamin E
In the study, 84% of the US population fell short on vitamin E intake. The RDA for vitamin E is 15 mg/day (22.4 IU),3 and optimal daily intake for immune health for older adults is 134 mg/day (200 IU).9 But the usual intake for vitamin E was only 9 mg/day.
What does zinc do for the immune system?
Zinc is an essential mineral that plays many vital roles in the body, including its role in maintaining the integrity of the immune system. It helps build immune cells and maintains their activity while also playing a role in the antioxidant defense system.†
What the study found about zinc
In the study, 15% were low in zinc intake. The RDA for zinc is 8–11 mg, which is adequate for healthy populations.10 The optimal daily intake for immune health for older adults has been suggested at 30 mg/day, which is higher than the usual intake of 12 mg.11
Strive to give your body more than the bare minimum
Immune health nutrients like vitamin C and vitamin D may get all the attention, but zinc, vitamin A, and vitamin E are all essential to our immune system support too. And the data shows most of us aren’t getting enough of any of these nutrients. †
While it’s tempting to look at our one serving of vegetables in a day and think, “this must be enough to meet my needs, right?”— it’s not. The reality is that many of us aren’t even meeting the bare minimum for essential nutrients, let alone the amount we need to support our optimal health. And when it comes to our health, shouldn’t we be striving for the best?
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Carroll is a nutrition scientist and communicator with over 25 years of experience as a clinician, researcher, and educator at major universities, medical centers, and nutrition industry settings. She is a passionate advocate of nutritional health and established the nutrition education and science platforms at Pharmavite. Carroll is an expert in personalized nutrition and has published several scientific papers on vitamin and mineral inadequacies and the impact on health and wellbeing. Prior to joining Pharmavite, Carroll taught nutrition at UCLA Medical School and Santa Monica College and was a chief clinical dietitian and researcher.