Ascorbic Acid: Vitamin C Benefits, Sources & Cautions

Katie Wells Avatar

Reading Time: 7 minutes

This post contains affiliate links.

Read my affiliate policy.

Wellness Mama » Blog » Health » Ascorbic Acid: Vitamin C Benefits, Sources & Cautions

Vitamin C has a rich and surprisingly controversial history. On the one hand, science is clear that the body needs it, but the type, dose, and frequency are all up for debate.

When the common cold is making the rounds, many people turn to vitamin C, also known as ascorbic acid, to help ward off illness. Without it, immune system function declines. Studies also show that without adequate vitamin C the lining of blood vessels and membranes of cells deteriorate. It is a big deal!

But, before downing a lot of prepackaged packets of vitamin C (probably with artificial colors and sweeteners), it is important to understand which forms of are most effective and how to safely consume it.

What is Vitamin C?

Vitamin C is a water-soluble vitamin that is needed for many reactions within the body. Humans are not capable of making it internally (most other animals can manufacture it in their livers). Vitamin C is present in many foods, especially brightly colored vegetables like bell peppers and citrus fruits, among others.

Since the human body does not manufacture or store vitamin C, it must be obtained regularly from diet (or supplements). Though low level vitamin C deficiency is common, severe deficiency (also known as scurvy) is rare in modern times.

Vitamin C is a powerful antioxidant, meaning it can help protect the body from the damage of free radicals. On a practical level, this means that it protects cellular health, reduces the effects of aging, and boosts the immune system.

I first learned about the benefits of vitamin C in high school when I had to do a research paper on Dr. Linus Pauling, a Nobel Prize-winning chemist who is considered one of the fathers of biochemistry. He spent much of his career studying vitamin C and even wrote several books on the vitamin’s impact on health. His work provided much of the current understanding of this important vitamin.

How Much Vitamin C Do We Need?

Vitamin C- sources benefits and cautions

Now, things are going to get hairy. The answer is that it depends on who you ask and when.

Modern research is divided and every health expert seems to have a different opinion. Like many aspects of health, the answer is likely that it depends and that it is different for every individual.

For many healthy people, it is likely possible to get enough vitamin C from rich food sources like certain fruits and vegetables. Certain supplements also contain just whole-food sources of vitamin C and can be beneficial for those wanting to slightly increase their vitamin C consumption.

Research shows that those with certain conditions may benefit from supplemental vitamin C as well, sometimes even in the form of an IV. In fact, some doctors are experimenting with high-dose IV dosing to help in recovery from serious illnesses, surgery, and even cancer.

Linus Pauling himself was rumored to take 12,000 mg or more of vitamin C a day (and he lived to 93)! Since up to a third of people are deficient in vitamin C, it can be important to supplement, but the type absolutely matters!

See what I personally do at the bottom of this post, but do your own research and talk to your own doctor to see what is best for you.

Benefits of Vitamin C

Today, even more science backs up the benefits of optimal amounts of vitamin C. Here are the main health benefits of vitamin C according to current medical research:

1. Boosts the Immune System

Perhaps the most well known benefit, and with good reason. Administering extra vitamin C is always part of my cold and flu protocol. Interestingly, this is also one of the more hotly debated benefits. Several reviews of all randomized controlled data showed little or no effect on colds from vitamin C supplementation. Most of these studies looked at small doses or at the effect after the onset of colds.

Other studies showed benefit from larger doses and from taking vitamin C before the onset of illness. Most notably, one study showed a reduction in symptoms and duration of a cold from one 8 gram dose of ascorbic acid on the first day of symptoms. (Fair warning, a dose that big will likely reach “bowel tolerance” and mean diarrhea for a few hours).

What I do: I start each day with the juice of one lemon in water, which yields about 30 mg vitamin C. I take a food-based vitamin C supplement daily. I also take bigger doses of ascorbic acid during times of stress or illness … more on that below.

2. Supports the Brain

A lesser known but equally important benefit of vitamin C (and why it is part of my daily routine).

The brain maintains vitamin C levels even with other parts of the body show signs of deficiency. In fact, the brain often has 100x concentration as the rest of the body and likely for good reason!

Vitamin C helps the brain in several important ways:

  • reduces reactive oxygen species and protects against neural damage
  • promotes the healthy development of neurons and supports the formation of myelin
  • supports optimal neurotransmitter production
  • leads to expression of BDNF (brain-derived-neurotropic-factor)
  • may even help avoid Alzheimer’s Disease according to recent studies

3. Fights Oxidative Damage in the Body

As you are probably already aware, free radicals and oxidative damage are bad news.

Vitamin C is a potent antioxidant that correlates with reduced risk of disease and longer lifespan, likely because of its ability to reduce oxidative damage and free radicals.

Specifically, studies have found that vitamin C is especially effective at reducing damage in the lungs. This is why RDA guidelines recommend higher vitamin C intake for smokers. Ascorbic acid is also sometimes used in conjunction with cancer treatments to help mitigate oxidative damage.

For those of us who (hopefully) don’t smoke or have cancer, a diet rich in vitamin C and some occasional supplements will likely just help keep inflammation at bay.

4. Boosts Mood and Libido

I notice I am generally happier and feel better when I get enough vitamin C. (And vitamin D, but that is a topic for another day). But science supports my anecdotal finding…

Studies link severe deficiency of vitamin C to emotional instability and anxiety. In one study adequate consumption led to a 35% reduction in mood disturbances and increased oxytocin. Yet another study found an increase in libido from 3,000 mg a day supplementation.

Yet another reason to start the day with lemon water!

5. Promotes a Healthy Heart

The jury is still out on this one, but some studies show that diets high in vitamin C seem to reduce the chance of heart disease and stroke. This is logical, since vitamin C is naturally found in fruits and vegetables and consuming enough of these is also great for the heart.

Another study showed that vitamin C may increase HDL cholesterol and reduce small particle LDL. The latest research even shows that this vitamin may reduce arterial plaque and strengthen blood vessels.

6. Boosts Collagen Production and Improve Skin

Internal and topical vitamin C can help increase collagen production and improve skin health.

Vitamin C helps stabilize collagen and improves the connective tissue in the entire body, including the skin and bones. It is widely used in beauty products since it induces collagen synthesis. Studies even show that it may slow the natural aging process by protecting and improving the body’s collagen.

Topical treatments are clinically shown to reduce the appearance of wrinkles, lines, and sun spots. I often mix a little ascorbic acid powder into my face wash to get these benefits. I also make this facial serum for additional skin benefits.

7. Supports the Adrenals

I also increase my intake of “C” when I’m stressed because it is directly used by the adrenals.

Though this tidbit is less well known, vitamin C is necessary for healthy levels of cortisol. It is found in high concentrations in the adrenal glands and can become rapidly depleted during times of stress.

Types of Vitamin C

Vitamin C is naturally found in many foods, and when possible, this is the best and safest way to consume it. As I’ve said before, you can’t out supplement a bad diet, so even if supplements are needed, diet must come first.

A note on vitamin C and when to consume/take it: vitamin C also helps the absorption of iron, so I try to take it with meals where I eat a real food source of iron.

Food Sources

To get vitamin C from food, consume plenty of raw vegetables and fruits like brightly colored bell peppers, citrus fruits, acerola cherry, broccoli, cauliflower, and others. This is just good advice in general but also great for ensuring healthy levels of vitamin C.

As I mentioned, my regular go-to is drinking lemon water each morning.

Food-Based Supplements

Even with the best of diets, getting adequate vitamin C from food can sometimes be difficult or not possible. In fact, it’s one of only five supplements that Chris Kresser recommends supplementing with since it can be so hard to obtain from food.

Unfortunately, heating destroys much of the vitamin content in food, so unless a person is consuming a wide variety of raw brightly colored fruits and vegetables daily (which is difficult in the winter months), supplementation can sometimes be helpful. Studies have also shown that the nutrients in food have declined over the last 50 years, and this includes vitamin C.

What I Take Daily:

I take a food-based C supplement daily because it is a relatively small dose and makes up for nutrients that aren’t present in food anymore. My favorite is this Essential C Complex.

Ascorbic Acid

The least expensive and most-studied type of vitamin C is ascorbic acid powder. I keep a big bag of non-GMO ascorbic acid around for use at the first sign of illness but don’t take it daily. I also mix ascorbic acid into one-time use skin applications like face masks and into my daily cleanser. It loses its effectiveness quickly when mixed with liquid so it doesn’t work as well for topical uses when pre-mixed into big batches.

Liposomal C

This form uses a specialized technology that is said to make it more bioavailable and much less acidic. My kids love the taste of this one and take it willingly so I always keep it around. It also has great reviews for skin health and I’ve been experimenting with making it part of my daily routine along with a liposomal turmeric.

Cautions and Risks

This essential vitamin is water soluble and generally considered safe at doses up to 2,000 mg a day, according to the Mayo Clinic. At doses larger than that, it can potentially be problematic. Diarrhea is the most common side effect. At extremely large doses, vitamin C may also carry the risk of increasing the likelihood of kidney disease. Pregnant women should also not take doses above the recommended daily amount as it may cause problems for baby.

This article was medically reviewed by Dr. Scott Soerries, MD, Family Physician and Medical Director of SteadyMD. As always, this is not personal medical advice and we recommend that you talk with your doctor.

What do you think about vitamin C? Do you take it or try to obtain it from food?

Katie Wells Avatar

About Katie Wells

Katie Wells, CTNC, MCHC, Founder of Wellness Mama and Co-founder of Wellnesse, has a background in research, journalism, and nutrition. As a mom of six, she turned to research and took health into her own hands to find answers to her health problems. is the culmination of her thousands of hours of research and all posts are medically reviewed and verified by the Wellness Mama research team. Katie is also the author of the bestselling books The Wellness Mama Cookbook and The Wellness Mama 5-Step Lifestyle Detox.


158 responses to “Ascorbic Acid: Vitamin C Benefits, Sources & Cautions”

  1. J. Ireland Avatar
    J. Ireland

    The ascorbic acid link you provide is to powdered ascorbic acid made in China and no where says it is non GMO so you are misleading readers. Ascorbic acid and citric acid are usually manufactured cheaply from growing a mold on corn syrup and there are people who cannot use it who have a sensitivity to either corn, mold, or GMOs. Someone even commented on Amazon that if the company is in the USA, they assume the product is made in the USA! I hate to say it but it is not the case! I would never use a manufactured ascorbic acid source from China.

  2. Rich Coulter Avatar
    Rich Coulter

    Katrina the laughable, completely devoid of all citations, blog you’ve listed as a source is a manufacturer of “natural vitamin C complex” – please go ahead and present any scientifically documented evidence of this “complex” having cured any ailment in history.

    Meanwhile the entirety of several decades of ascorbic acid being used to treat whooping cough, influenza, polio, shingles, chickenpox, measles, and on and on and on and on, refers to ascorbic acid, C6H8O6, also known as vitamin C.

    Dr. Klenner’s C papers –
    Vitamin C Foundation on the natural complex myth –
    Dr. Thomas Levy on the myth –

    Cost of vitamin C from Dr’s Best using Quali-C from Scotland (non-GMO), pure ascorbic acid powder – 250 grams for $15 from Amazon US – there are 250g of C per bottle thus cost is $0.06/gram

    Cost of vitamin C from Radiant Life – 120g powder of which each 650mg serving provides 120mg of vitamin C, so there are 180 servings of 120mg of C, so there are 21.6 grams of C per bottle thus cost is $1.25/gram

    The Radiant Life product is almost 21 times as expensive. What a ripoff.

  3. Jan Avatar

    This is very interesting. I use powdered ascorbic acid I my laundry rinse cycle because I am sensitive/allergic to chlorine. After using this, however, for a couple of years now, I seem, to have a rash starting on my face and not sure if it is the Vit C or if chlorine is still on the items laundered (eg bed linens, etc.). If you have more info on using Vit C in facial creams etc. and the Lipsomal, I’d be very interesting in hearing how you use them. I tried putting the powdered Vit C in some moisturizer cream, but it eventually/soon went rancid. Thanks

  4. Lisa Avatar

    Wellness Mama,
    I love all the information you put out but I really think that you need to do more research on ascorbic acid. Numerous studies show and support the fact it does more harm than good.

  5. Caralyn Avatar

    Dr. Suzanne Humphries, world renowned expert on vitamin C offers some wonderful facts about ascorbic acid and her preferences. Interesting and incredibly useful information your readership can add to the important information that you shared.

  6. Lee Avatar

    If the antioxidant system is blocked and a person does not address that issue the taking high dose vitamin C will actually do the opposite because it can raise reactive oxygen species. Also megadoses of vitamin C can cause anemia because it breaks down read blood cells and it can cause zinc and copper deficiencies.

  7. Summer Avatar

    Hi there! I give my children (ages 4 & 9 ) vitamin C daily. But can they take Pure Radiance? I want them to get the best quality they can thank u. Summer

  8. Naomi Avatar

    This article is very helpful, Ive developed stomach issues in my 20’s & was told I was “allergic” to many things, including the vitamin C supplements. Right now I’ve been practicing the Paleo diet for health/stomach reasons which I’ve found to be a lifesaver. It’s so interesting to realize everything on that list of things I can’t eat, besides for fruits high in acidity, is on the Paleo ‘not to eat’ list. I didn’t even realize that the vitamin wasn’t the same as the natural vitamin C & affects gut bacteria – which I’ll add has been proven to have a direct correlation with Depression & other mental health symptoms.

  9. Tanis Avatar

    Interesting article but then it raises the question on why in the preventvention of certain. childhood cancers are there recommendations for high vitamin c ?

  10. Steven Burke Avatar
    Steven Burke

    Please DO NOT stop giving your kids ascorbic acid, that IS vitamin C! Of the thousands of scientifically sound, peer-reviewed and published studies written about Vitamin C and every account of every instance vitamin C has saved lives, it is ASCORBIC ACID being referred to.

    It’s criminal that this website keeps this misinformation, rebutted countless time, online and it’s painful to read Annabelle’s comment that this article is causing her to no longer administer vitamin C but some quackery – no-one can post a single scientifically sound article explaining what Factor J is. Total BS.

    Shame on Wellness Mama!

  11. Annabelle Avatar

    Wow. This article is a real eye opener to me. I supplement my kids with vitamin c, especially in the winter months, to ward off colds, not knowing the difference and the importance about how its made. I ran to check what they were made of; nothing but ascorbic acid. I felt really bad about it and immediatelly stopped giving it to them and instead bought more mandarins, strawberries and orange juice than usually. Thank you for much for this article and may God continue to bless you with knowledge to share with the rest of the world.

  12. Inger Avatar

    Thank you for doing the work for me — I’ve been looking for a quality vit. C supplement. Order placed (from your link).

  13. Jeanette Avatar

    Is vital C injections for beauty reasons advisable when one get diverticulitus & has a duodenal ulcer?

  14. Yvonne Avatar

    What’s the best vitamin c supplement for young kids? I feel like they get sick soon after school starts and need an immune boost.

  15. Jill Avatar

    Would you recommend the Pure Radiance C brand to add to baths to neutralize the THM’s? Or would this be less effective bc it doesnt contain sodium? Thanks

  16. Daniela Avatar

    Funnny, my sister had some health struggles recently and that’s exactly what the lady in our local pharmacy said. She recommended organic acerola juice as the synthetic Vitamin C would do absolutely nothing for her. Great article.

  17. Tom Avatar

    people that promote the principle of a ‘real’ or ‘natural’ vitamin C and say ascorbic acid is not good for you only are misguided or misinformed.

    you cannot change the history nor chemistry of vitamin C to fit a belief that is not supported anywhere in any medical literature that spans 80+ yrs on vitamin C.
    it simply does not work that way.

    If such a complex ( real or natural) really exists with vitamin C activity (minus ascorbic acid), this fact escaped the attention of all world scientists, including Linus Pauling. Such a complex is not reported in over 100,000 published studies, papers, reports and scientific articles regarding ascorbic acid (C6H8O6).

    Bioflavanoids or the ‘co-factors’ alone will not prevent, reverse, and cure disease. Yet, ascorbic acid will. Chemistry and anatomy will explain the whole thing. Honestly anyone that has no knowledge of these two thing has no knowledge of ascorbic acid. Ascorbic acid donates electrons. In high doses the body has constant electron flow negating oxidative damage and protecting cells from death. The route cause of all illness and disease. Prove that bioflavanoids in such high doses is safe and we will talk. Did you know humans once produced ascorbic acid in our livers?! We never produced bioflavanoids. After all we are not plants.

    No one who is engaged in conventional medical research believes there is a C-complex, ‘real’ or ‘natural’ C.. nor are there any peer-reviewed papers accessible in the Medline medical database that support the idea that there is a C-complex, much less that it is the real vitamin C.

Leave a Reply

Your email address will not be published. Required fields are marked *