Is Ascorbic Acid In Your Health & Beauty Routine? Here’s Why It Should Be

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The world of supplements and topicals can be overwhelming. Many products, after all, have ingredient labels that look like they’re right out of a chemistry textbook. 

One common term that you’ll likely see is “ascorbic acid,” which can admittedly sound a bit scary (er, acid?) but is one of the most important nutrients you can add to your routine. 

Read on to learn about what ascorbic acid is used for, some health benefits, plus how much you should take.

That said, the terms “ascorbic acid” and “vitamin C” are often used interchangeably. So, from here on out, we’ll use both words to refer to the nutrient.

A quick science lesson: Vitamin C is a water-soluble vitamin. It’s an essential micronutrient, meaning the human body is unable to make its own (unlike most other animals that are able to synthesize the vitamin). 

The reason? Humans don’t have L-gulonolactone oxidase, the enzyme needed to make vitamin C. Hence, we need to get our vitamin C via food and supplements.

Ascorbic acid is also a topical ingredient, meaning it can be applied to the skin. This has excellent benefits for skin health, as you’ll soon see below.

“Vitamin C is a potent antioxidant, [meaning it] neutralizes free radicals that result in increased oxidative stress,”* explains registered dietitian and holistic nutritionist Ella Davar, R.D., CDN. 

A quick explainer: Free radicals are unstable molecules. Many factors—like billions of cellular reactions in our body, mental or emotional pressure, UV exposure, smoking cigarettes, and air pollution—increase your body’s free radical production. Over time, this accumulation of free radicals can lead to an imbalance (aka oxidative stress), but antioxidants like vitamin C help protect against these effects and keep things in balance.*

Additionally, “Vitamin C recycles other antioxidants in the body, such as vitamin E,”* says Davar. This is noteworthy, considering vitamin E is an antioxidant that also offers a protective role against reactive oxygen species (ROS). 

Plus, the antioxidant activity of vitamin C is a win-win as it delivers anti-inflammatory benefits, too.* A 2020 Frontiers scientific review notes that the nutrient does this by helping to decrease the production of cytokines derived from leukocytes (i.e., white blood cells) by combating ROS.*

Ascorbic acid is a beloved nutrient for skin care for a few key reasons. Vitamin C’s primary benefit for skin? It’s a vital component for producing collagen, the main structural protein in the skin (and the most abundant protein in the entire body!).* 

According to Alexander Michels, Ph.D., clinical research coordinator at the Linus Pauling Institute at Oregon State University, vitamin C is also needed to support normal collagen cross-linking, which ensures that the protein chain is strong and resilient.* 

While factors like aging, UV exposure, stress, and lack of adequate amino acid building blocks can all reduce collagen levels—and therefore, contribute to skin changes like fine lines, wrinkles, and loss of elasticity—using both oral vitamin C supplements and topical vitamin C products can help protect said collagen.*

Since ROS contribute to the skin’s aging process, the antioxidant activity of ascorbic acid also lends a hand in reducing wrinkles.*

“Vitamin C is [also] necessary for the growth, development, and repair of bodily tissue,” adds Davar, making it crucial for skin healing.* Ultimately, ascorbic acid “helps us deal with the wear and tear that our skin experiences on a daily basis,”* says Michels.

And considering our skin is a living organ and our first barrier or line of defense, we’re here for it (i.e., vitamin C’s many skin-essential benefits).*

That’s right, ascorbic acid can support cardiovascular health too!* This is partly due to its role in collagen production, as the protein gives structure to your blood vessels and heart (as we said before, collagen is everywhere).* 

The antioxidant activity of vitamin C also protects endothelial cells (i.e., the cells lining the blood vessels) from ROS.* This cardioprotective role has whole-body relevance because endothelial health means normal contraction and relaxation of blood vessels, along with blood clotting and immune function pathways.

Additionally, a meta-analysis published by the American Journal of Clinical Nutrition found that oral vitamin C supplementation promotes healthy blood pressure levels.* Another compelling study from Nutrition Journal found similar results, noting that the effect on blood pressure is likely due to vitamin C’s antioxidant properties.*

Between its high rate of metabolism and consumption of oxygen, the brain is exceptionally susceptible to ROS. This is notable because ROS contributes to brain aging later in life and loss of nerve cell function over time. 

Fortunately, the antioxidant properties of ascorbic acid can buffer the effects of oxidative stress while helping to protect the existing antioxidants in the brain, says Michels.*

Ascorbic acid is also a cofactor in reactions required to make neurotransmitters (e.g., dopamine, serotonin, and adrenaline), which are involved in everything from mood to sleep.*

And if that wasn’t enough to prove the harmonious relationship between the bodies’ processes and essential nutrients, the production of collagen (which, again, relies on vitamin C) “keeps blood vessels within the brain strong, maintaining critical blood flow throughout the organ,”* notes Michels. Similarly, collagen is linked to the proper development of the myelin sheath, or the layers of tissue that protect nerves, so they can quickly and most effectively send their signals from neuron to neuron.* 

In fact, vitamin C is so crucial to brain support that the body delivers the nutrient to the brain before any other organ, says Michels.*

Vitamin C is famously known for supporting immune function and response, which it does in myriad ways.* For starters, as it promotes collagen synthesis, it strengthens the body’s epithelial barriers, including the skin (again, your body’s first line of defense).* 

Vitamin C is also involved in the function of leukocytes, specialized white blood cells that target foreign substances in the body.* Even the antioxidant properties of vitamin C come into play here, as redox balance (i.e., equilibrium of antioxidants vs. oxidants) can affect your immune system.* 

In a way, you can think of vitamin C as one of your cells’ most loyal supporters.

In addition to your skin, blood vessels, and heart, vitamin-C-dependent collagen is crucial for healthy joints.* Specifically, the protein gives structure to cartilage, the layer of connective tissue that cushions your joints. 

This is especially important to consider as you get older, as both collagen levels and joint integrity tend to decline over time. And if that wasn’t enough to appreciate vitamin C, it protects the collagen you have by combating enzymes that break down the protein.*

Like the brain, the eyes have a high rate of metabolism. This makes them vulnerable to ROS, but the antioxidant properties of ascorbic acid can offer a protective role.* 

As mentioned before, vitamin C also helps regenerate vitamin E, its partner in crime that offers additional antioxidant benefits in the eye.* And get this: Vitamin C’s antioxidant activity helps protect the lens by shielding the eyes against UV light, according to a Nutrients 2020 scientific review.*

• Food. Ascorbic acid is the type of vitamin C that’s naturally found in foods. Citrus fruits, like oranges and lemons, and superfruits like acerola cherries, are especially rich in vitamin C—though you can also get the essential nutrient from a variety of produce like strawberries, broccoli, and even potatoes.
• Daily supplements. As one of the most common types of vitamin C used in supplements, ascorbic acid is available on its own in a vitamin C supplement, or in multis (like mbg’s ultimate multivitamin+). These supplements are also available in different forms, including capsules, liquids, and powders.
• Topical skin care products. “Vitamin C can be found in a range of skin care products, such as cleansers, eye creams, [and] moisturizers,” says medical esthetician and celebrity makeup artist Tiffany Lee. However, it’s most commonly found in serums for targeted treatments.

When it comes to the best dosage of ascorbic acid supplements, it helps to understand how the nutrient is absorbed by the body.

“We have transport proteins in our small intestine that regulate how much ascorbic acid can pass through the gut [and] into the bloodstream,” explains Michels. And while there are multiple transport proteins that regulate how much ascorbic acid can cross over, they all become flooded when you take more ascorbic acid than they can handle (about 400 milligrams), he says. 

As a result, “the rest of that vitamin C just gets pushed through your gastrointestinal tract and is lost [in the urine],” notes Michels. What a bummer.

Fortunately, it is possible to maximize your blood concentrations of vitamin C. If you’re taking pure ascorbic acid (i.e., more than 300 to 400 milligrams per serving), the best plan is to break it up into two or three doses and spread them out throughout the day. 

“This way, the transport proteins have [a lower] chance of being overwhelmed, and more vitamin C will get through the bloodstream,” says Michels.

It’s worth noting that most scientific studies, especially those on the link between vitamin C and immune function, involve doses at 500 or 1,000 milligrams—and sometimes higher. So, for higher doses, you’ll want to be extra mindful of the type of vitamin C in your supplement so you can optimize absorption.

That’s why mindbodygreen’s vitamin C potency+ uses a clinically researched and highly bioavailable combo of vitamin C (a 1,000-milligram dose, to be exact), lipids (fatty acids from rice bran), and citrus bioflavonoids (phytonutrients from bitter orange).* So it’s a complex or trio, with C as the leading actor, and the lipids plus citrus bioflavonoids as the supporting actors.

When taken together, the lipids help vitamin C move through lipid membranes, while the citrus bioflavonoids help buffer the C from oxidation.* For the record, this translates into a 233% higher cellular absorption rate of vitamin C compared to pure ascorbic acid.*†

The upper limit of vitamin C is 2,000 milligrams a day (as per the National Academies), meaning it’s totally safe for most adults to take up to that dose of vitamin C every day.

In fact, a Free Radical Biology & Medicine study found that higher doses of vitamin C can deliver additional health benefits—but be sure to get the green light from your health care provider before starting a high-potency vitamin C supplement.*

The safety profile of ascorbic acid is very high, but like all supplements, vitamin C may have contraindications, which is why it’s always best to contact your health care provider to determine if ascorbic acid has a place in your supplement or skin care routine.

If you have specific health considerations or sensitivity related to your kidneys, you may want to steer clear of vitamin C. “Excessive supplementation (more than 2,000 milligrams a day) over a prolonged period of time can increase urinary oxalate and uric acid excretion,” says Davar. 

In skin care products, “vitamin C is not recommended for those with sensitive skin,” says Lee. The ingredient can cause redness and dryness, especially if it’s used without sunscreen. Your dermatologist can let you know if the ingredient is right for you.

Ascorbic acid is a form of vitamin C that’s found in food, supplements, and topical products. It’s a potent antioxidant, making it a powerful essential nutrient for promoting healthy skin, eyes, immune response, joints, and brain function.* 

If you’re looking for a daily supplement that supports whole-body health, vitamin C might be just what your routine needs.*