What Are Vitamin C Supplements Good For? Benefits For Skin & More*

As an essential micronutrient with myriad physiological functions, vitamin C can do some pretty incredible things for the body.* Yes, that includes strengthening your immune system—but also much more.*

Moreover, humans are some of the few mammals who can't make our own vitamin C, so it's critical to get enough through diet (and supplements can help, too) every day.

For example, it promotes multiplication of lymphocytes1—a type of white blood cell—to combat foreign invaders in the body.*

Vitamin C also helps neutrophils2, another type of white blood cell, "eat" and destroy bad microbes.* All in all, these are quite amazing (and specific) actions for our immune response.

The antioxidative properties of vitamin C protect the immune system, too.* Acute oxidative stress is normal and useful for immune function, but prolonged oxidative stress is not normal, nor good for overall health.

Oxidative stress happens when your body produces free radicals, and it's a normal outcome of our immune cells (and many other cellular processes throughout the body) doing their hard work to protect us.

Antioxidants like vitamin C are compounds3 that combat oxidative stress by neutralizing free radicals.* They are critical to strike a healthy oxidative balance in the body.*

According to Keira Barr, M.D., dual board-certified dermatologist, vitamin C4 helps protect your skin from free radical exposure (like UV rays and air pollution).* This helps pump the brakes on many types of skin woes, including the impact of sun exposure5, hyperpigmentation, and wrinkles.* 

For optimal skin benefits, Barr suggests both supplementing with vitamin C and applying it topically—a tandem approach.* This ensures that there is enough vitamin C biologically available and active in and on the skin.*

Collagen is essential for strong and supple skin. As a major protein in our body, it also gives structure to other connective tissues6—including blood vessels, tendons, the gut, and more.

But as we get older, our body's usual formation of collagen naturally decreases7, leading to thinner skin and less of this major building block for our various tissues' architectural support and healing.

When it comes to brain health, nutrients like omega-3 fatty acids frequently steal the show. But did you know vitamin C plays a role, too? Once again, this is due to its core antioxidant actions.

"Free radicals can cause wear and tear to all parts of the body, including the brain and mind," explains Foley. However, as an antioxidant, vitamin C can help combat oxidative stress to support cognitive functions.*

Vitamin C is important for the health of nerve cells as well, and those neurons send signals to and from the brain our entire lives!* "It supports the myelin sheath9 that protects [neurons], allowing for quicker impulse transmissions and quicker signals,"* says Amy Shapiro, M.S., R.D., CDN.

Taking vitamin C supplements may help support healthy blood pressure levels.* Why? Well, this water-soluble micronutrient promotes the body's production of a molecule called nitric oxide11.

Nitric oxide is a powerful vasodilator, which means it dilates, or opens, blood vessels, which is critical for their optimal function and helps lower blood pressure.*

But wait—there's more. Vitamin C has diuretic properties, "causing the kidneys to remove more sodium and water from the body,"* says Foley. This "helps relax blood vessel walls and lower blood pressure."*

It can also maintain or restore flexibility in artery cell walls, which decreases plaque formation and improves blood flow, she adds.*

Iron absorption12 is a fickle, complex process. It depends on many factors, including the form (and source) of iron and your existing iron stores.

It's also influenced by your intake of vitamin C, which plays a supportive role in iron absorption.* According to Shapiro, it turns non-heme iron—which is found in plants—into a more absorbable form.* (Vitamin C does this by supporting the solubility of iron in the small intestine).* This is important because non-heme iron (found in plant sources) isn't as bioavailable as heme iron from animal sources.

Overall, taking vitamin C supplements or a multi-ingredient supplement with vitamin C is considered safe for most individuals. People with a history of kidney stone concerns should take caution, as too much vitamin C can potentially increase oxalates and worsen or increase kidney stone issues14 (i.e., too much means high-dose vitamin C above the tolerated upper limit of 2,000 milligrams).

As always, individuals with key health concerns should check with their healthcare provider before starting any new supplement regimen.

There's a reason vitamin C gets so much praise for its plethora of health benefits: It really is a do-it-all vitamin, supporting whole-body antioxidant actions, plus immune, skin, cognitive, and cardiovascular health.*

"Ideally, you're getting vitamin C from food, yet it can be hard to get enough in the diet to reap all of [its] benefits," notes Foley. Vitamin C is a common gap in the American diet—in fact, 46% of U.S. adults15 aren't consuming adequate amounts of vitamin C.