Your immune system is an intricate network of organs, specialized cells and proteins that comprise your natural defenses and work together to keep you in top-notch health. Not surprisingly, immune support supplements are popular choices for people who want to support immune function, with vitamin C supplements at or near the top of the list.
However, according to Stephen Tapanes, PhD, people get confused about vitamin C (aka ascorbic acid). Indeed, this vitamin is a cofactor or “helper molecule” in many immune function pathways and helps protect cells from oxidative stress. “But there are some misconceptions about vitamin C,” said Dr. Tapanes, a scientist at Life Extension.
For example, people choose high doses of vitamin C supplements, thinking it is the best way to prepare themselves for health challenges. However, a higher dose of vitamin C may not mean more benefits—higher doses may increase plasma concentrations of vitamin C in your bloodstream, but your body will flush out what it doesn’t use.
So, how does the body use vitamin C to support immune function? And how do you take it for optimal absorption? Let’s peel back the layers of vitamin C’s role in immune health.
As a nutrient, vitamin C is one of the foundations for a healthy immune response, and vitamin C supplements can help strengthen that relationship in three ways:
Here’s a quick table summarizing how vitamin C works in the body.
You need to have healthy vitamin C levels all the time, not just when a specific challenge comes your way, to ensure it can do this important work.
White blood cells are specialized immune cells that are your body’s tiny defenders. There are several types of white blood cells, but, in general, they patrol your bloodstream, protect your cells, and keep tissues healthy; more specialized white blood cells remember past immune challenges.
Vitamin C intake helps keep your immune system strong by promoting the production and function of white blood cells. For example, vitamin C supports phagocytosis, a cellular process where macrophages (a type of white blood cell) gobble up and destroy undesirable immune intruders. Vitamin C also helps with cell signaling or “cell communication,” so they know what to look for, how to eliminate it, and when to step back, explained Dr. Tapanes.
As a free-radical scavenger, vitamin C’s antioxidant properties support immune and overall health in three ways:
Insufficient vitamin C levels negatively impact how the immune system functions in two specific ways:
Observational studies have shown that vitamin C intake and exercise, on their own and in combination, are associated with a healthy inflammatory response and robust immune function, Dr. Tapanes added.
But if you do have low levels, one thing that likely will not help is to suddenly start taking it in large doses for a short time. “Taking large doses after facing immune challenges won’t make a difference because much of that vitamin C gets excreted from the body. What’s important to support your immune health is consistent intake, so your immune response is ready to go when it’s needed,” Dr. Tapanes said.
“Your body will absorb vitamin C from a conventional supplement, but they won’t help maintain enough vitamin C plasma concentrations that allow the body to use it before flushing it out.”
Given how important vitamin C is to staying healthy, many people look for the largest possible dose of it when shopping for a supplement—but this is a mistake, said Dr. Tapanes. “Your body will absorb vitamin C from a conventional supplement, but they won’t help maintain enough vitamin C plasma concentrations that allow the body to use it before flushing it out,” he explained.
An alternative that may keep vitamin C in your bloodstream for up to 24 hours: a liposomal vitamin C supplement, Dr. Tapanes said. Additionally, you can also choose vitamin C supplements in combination with quercetin, elderberry and other nutrients that complement the health-promoting benefits of vitamin C.
Vitamin C supplements come in different shapes and doses, including capsules, drops, effervescent tablets, and even chewables and gummies.
In general, to maintain healthy levels, you need a certain amount of vitamin C, which will vary by age and gender:
Some lifestyle habits, like smoking, can deplete vitamin C levels in the body. The National Institutes of Health recommends men who smoke to aim for 125 mg of vitamin C, and women who smoke should aim for 110 mg of daily dietary supplementation, Dr. Tapanes noted.
However, the minimum amount of vitamin C that’s recommended for daily consumption isn’t sufficient to support immune function and overall health. “To get the most of your vitamin C, you will likely need to regularly take a higher dose,” Dr. Tapanes said. “Many supplements provide a dose of 250-1000 mg to help maintain optimal levels that are associated with health benefits.” You should always follow the instructions on the label when taking a vitamin C (or any) supplement.
—It’s not uncommon to reach for some vitamin C supplements when we’re experiencing immune challenges. Unfortunately, a higher intake of ascorbic acid when our defenses are already down won’t make us fight challenges faster.
—Oranges and orange juice may be rich in vitamin C, but they’re by no means the best or only source. You’ll find vitamin C in broccoli, Brussels sprouts, red bell pepper, and other fruits like strawberries, papaya, kiwi and pineapple.
—Your body gets rid of excess, but large doses are associated with digestive and other discomforts.
Ascorbic acid is packed with health-promoting benefits, says Dr. Tapanes. Nutrient-dense, whole foods should be your primary source of this essential vitamin. Here’s a quick list of excellent vitamin C sources:
Vegetables rich in vitamin C:
Fruits rich in vitamin C:
Yes, as Dr. Tapanes explained, it’s safe to take vitamin C daily. It’s always smart to speak with your healthcare provider to choose the best vitamin C supplement and dosage tailored to your needs.
A balanced diet filled with a variety of whole foods should be your primary source of vitamin C. A vitamin C supplement complements your smart lifestyle choices.
Unsure of how to support your immune health? Take our quiz to get personalized supplement recommendations.
Source: Life Extension Wellness
