Table of ContentsView AllTable of ContentsWhat Is Vitamin C?Benefits and UsesDeficiencySide EffectsPrecautionsDosageInteractionsStorageSources
Table of ContentsView All
View All
Table of Contents
What Is Vitamin C?
Benefits and Uses
Deficiency
Side Effects
Precautions
Dosage
Interactions
Storage
Sources
Vitamin C is touted for many potential health benefits, including boosting immunity, improving heart health, and bolstering iron absorption. It’s essential for tissue growth, development, and repair. As an antioxidant, it may help protect cells from free radicals—unstable molecules that damage cells. However, its benefits for specific diseases and conditions remain unproven.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
Vitamin C, orL-ascorbicacid, is an essential nutrient. The body can’t manufacture it, relying instead onvitamin C–rich foodssuch as berries, broccoli, cabbage,citrus fruits,kiwi,oranges, peppers, and tomatoes.In addition, vitamin C supplements are available as capsules, chewable tablets, and powder.
Research shows vitamin C has many general health benefits. However, the science is inconclusive on using vitamin C to treat or prevent specific health conditions.
Supplement FactsActive ingredient:Vitamin C, ascorbic acidAlternate names:Ascorbic acid, dehydroascorbic acidSuggested dose:Recommended dietary allowance ranges from 75 to 90 milligrams (mg) per day for adultsMaximum dose: Adults should not exceed 2,000 mg a daySafety considerations:Generally safe if taken as recommended
Supplement Facts
Active ingredient:Vitamin C, ascorbic acidAlternate names:Ascorbic acid, dehydroascorbic acidSuggested dose:Recommended dietary allowance ranges from 75 to 90 milligrams (mg) per day for adultsMaximum dose: Adults should not exceed 2,000 mg a daySafety considerations:Generally safe if taken as recommended
How Can Citric Acid Affect Your Health?
Vitamin C Benefits and Uses
Vitamin C has been marketed for use to treat and/or prevent many conditions, from thecommon coldandCOVID-19toarthritisandAlzheimer’s disease. Even so, there’s scant evidence to support most claims about vitamin C.
What researchers have learned is that vitamin C appears to play a lot of important roles in your body. The most beneficial aspect may be itsantioxidantactivity.
Get Medical AdviceSupplement use should be tailored to your specific health issues and needs. Before starting a supplement, talk to a qualified healthcare provider, such as a Registered Dietitian or pharmacist.
Get Medical Advice
Supplement use should be tailored to your specific health issues and needs. Before starting a supplement, talk to a qualified healthcare provider, such as a Registered Dietitian or pharmacist.
Vitamin C and Arthritis: Does It Work?
May Lower Risk of Chronic Illnesses
When you have a lot of free radicals in your system, it can cause a condition calledoxidative stress. Research has linked many chronic diseases to oxidative stress, including heart disease, rheumatoid arthritis, chronic obstructive pulmonary disease (COPD), and kidney disease.
However, research into using antioxidants to treat or prevent specific conditions has been a mixed bag.
Free radicals come in many types; some are harder for antioxidants to scavenge. Their location in your body can also make a difference, as certain environments (e.g., inside a cell versus in fluids outside the cell) can make the antioxidant activity more or less successful.
Moreover, researchers say it’s important to be “realistic about where, when and to what extent oxidative stress is part of a disease.“So, as they learn more about the disease processes and the role of oxidative stress, researchers may find roles for antioxidants like vitamin C.
In the meantime, while they’re generally considered good for your health, don’t expect vitamin C or any other antioxidants to take the place of other treatments.
What Causes Free Radicals?Molecules in your body become free radicals when they’re exposed to things like environmental pollutants, cigarette smoking, and chronic inflammation.
What Causes Free Radicals?
Molecules in your body become free radicals when they’re exposed to things like environmental pollutants, cigarette smoking, and chronic inflammation.
Benefits of Eating Rambutan
May Lower Heart Disease Risk
Oxidative stress is believed to play a role in the development of somecardiovascular diseases(“cardio” means heart, “vascular” refers to blood vessels).
A major reason for this is that oxidative stress can triggeratherosclerosis, which is the thickening or hardening of arteries due to plaque buildup fromcholesterol, fat, and other substances. This can lead tocoronary artery disease.
Studies have also suggested that oxidative stress may play some role in:
Even so, research into vitamin C for treating and preventing heart disease has mostly found no effect.
One promising bit of information came out in a 2020 study. It showed that vitamin C supplements helped lower blood pressure in people with hypertension.Hypertension, especially when combined with atherosclerosis, is a risk factor for heart disease.
May Help Reduce Risk of Certain Cancers
A lot of research has investigated the role of antioxidants, including vitamin C, in cancer care and prevention. However, the results have yielded inconsistent results.
Most studies have found that vitamin C supplementation, either on its own or in combination with other supplements, cannot prevent or treat cancer.
Some studies have shown that when used in supportive care, high-dose intravenous (IV) vitamin C can improve quality of life and reduce the side effects of standard cancer treatments.However, studies have also shown that antioxidants can have a downside. They may:
Some healthcare providers recommend eating more antioxidant-containing fruits and vegetables, as people with diets rich in vitamin C may have a lower risk of getting certain types of cancer. However, it’s important to remember that no one food will prevent cancer.
Moreover, vitamin C supplements themselves do not appear to prevent cancer. Eating a well-balanced diet in general, including antioxidants, is beneficial for your overall health.
Future studies are needed to establish the role of antioxidants like vitamin C in cancer. Talk to your oncologist before starting anysupplements during cancer treatment.
Can Prevent Gout Attacks
However, a 2021 review of studies concluded that, while results have been promising, more high-quality studies on humans need to be done to say for sure that it’s a safe and effective treatment or preventive measure.
Are Tomatoes Bad for Gout?
Prevents Iron-Deficiency Anemia
Withanemia, your blood doesn’t contain enough red blood cells, which carry oxygen from your lungs to your body’s tissues. The most common type of anemia involves adeficiency of iron, which your body needs to make red blood cells.
Vitamin C is known to help your body absorb some nutrients. Among healthcare providers, that led to a long-standing practice of recommending vitamin C supplements withiron supplementsfor treating anemia.
The different results may be related to what kind of iron people took. Nonheme iron from plant sources is better absorbed with vitamin C. Heme iron, the form found in meat, is better absorbed in general because it has higher bioavailability than nonheme iron.More research is needed to sort this out.
Vitamin C and Iron Supplements
Boosts Immunity and Speeds Healing
Studies show vitamin C’s effect on the immune system may help with certain infections, such as:
These abilities are believed to be largely due to vitamin C’s antioxidant activity along with its ability to promotecollagenproduction in the skin.
This is likely better achieved with nutritional intake (including supplements) rather than topically becausecollagenis present in deeper layers of skin and can’t penetrate the outer layers to get there.
What Is Collagen?Collagen is a protein in your body that makes tissues strong, resilient, and able to tolerate stretching. It’s in skin, bones, muscles, tendons, and cartilage.
What Is Collagen?
Collagen is a protein in your body that makes tissues strong, resilient, and able to tolerate stretching. It’s in skin, bones, muscles, tendons, and cartilage.
What Does Vitamin C Do for Your Skin?
Fights the Common Cold
Traditional wisdom about taking vitamin C for the common cold may not be as wise as you think. Research has provided mixed evidence about vitamin C for treating or preventing these respiratory infections.
Several studies, including a large systematic review of the evidence, suggest vitamin C supplements:
Even these points aren’t firmly conclusive, though, and some studies have found vitamin C may only have a minimal or no effect on how long your cold lasts.
More research needs to be done before researchers can draw any firm conclusions.
Slows Age-Related Macular Degeneration
Age-relatedmacular degeneration(AMD) is an eye disorder that can, over time, cause blindness. Research on whether vitamin C and other antioxidants can prevent AMD has been inconclusive. But some research suggests it may slow it down.
The Age-Related Eye Disease Study (AREDS), a large clinical trial, included almost 3,600 older adults with AMD. The participants were divided into four groups and given different treatments:
After six years, the participants who got supplements had less AMD progression.However, researchers can’t be sure that vitamin C itself made a difference.
This is an older study, though, and since then, a number of other studies have failed to show that vitamin C alone is helpful against AMD.However, a 2023 Cochrane review found vitamin C, taken alone with vitamin E, beta‐carotene, andzinc, probably slows down progression to late AMD.
Vitamins and Minerals for Eye Health
Protects Brain Health
Vitamin C’s antioxidant activity may play a role inbrainhealth.
Research suggests regular dietary intake plus supplements may protect you from neurodegeneration related to aging and diseases such as:
Vitamin C may even help treat or lower your risk of mental health disorders, including:
Studies suggest vitamin C deficiency may contribute to the development of these mental and neurodegenerative conditions and that supplementation may help alleviate symptoms. However, this work is preliminary, and more research is needed.
Vitamin C Deficiency
Vitamin C deficiencyis rare in developed countries. In the United States, only about 8.4% of the population is believed to be vitamin C deficient.
You’d have to get less than 10 milligrams (mg) per day from food for about a month to feel the effects of a vitamin C deficiency. In severe cases, this can lead toscurvy(which is rare in the U.S.).
Symptoms of scurvy include:
Vitamin C deficiency is treated with vitamin C supplements. Some symptoms improve within the first 24 hours of treatment. Others may take a few weeks or months to resolve.
What Causes a Vitamin C Deficiency?
A deficiency occurs either from insufficient nutrient intake in the diet or increased losses due to poor absorption.
People who don’t consume various foods, mainly fruits and vegetables, are at greater risk of vitamin C deficiency. Smokers have a higher requirement for vitamin C, so smoking may also be a risk factor.
Additionally, people with malabsorption disorders may become deficient because they can’t absorb enough vitamin C.
How Do I Know if I Have a Vitamin C Deficiency?
Symptoms of a vitamin C deficiency include:
If you have these symptoms and know your vitamin C intake is low, or if you rarely eat fruits and vegetables, talk with your healthcare provider about whether supplements are right for you.
7 Nutrient Deficiencies That Can Make You Sick
What Are the Side Effects of Vitamin C?
Vitamin C is generally considered safe, but high doses can cause side effects. These may include:
Higher doses are more likely to lead to side effects. Doses over 2,000 milligrams a day may increase the risk of diarrhea and kidney stones. If you have a history of kidney stones, taking more than 1,000 milligrams a day may increase your chances of having more.
Vitamin C supplements are not right for everyone. Talk to your healthcare provider first if you are experiencing any of the following:
Dosage: How Much Vitamin C Should I Get?
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
The RDA for vitamin C is as follows:
There are two important caveats to these recommendations:
Taking high doses may be appropriate for some people, but it usually provides no extra benefit. Your body controls how much vitamin C it absorbs.
The Best Time to Take Vitamin C Supplements, According to Science
Upper Limits
The tolerable upper intake level (TUL) is the highest amount you can safely take. Doses beyond that are more likely to cause side effects.
For vitamin C, the daily TUL is different for different groups:
Adults: 2,000 milligrams
Children:
Pregnant people: 2,000 milligrams for adults or less than 1,800 milligrams for teens
What Happens if I Take Too Much Vitamin C?
Excessive amounts of vitamin C (above TUL) can result in:
If you’re healthy, taking recommended levels of vitamin C supplements generally doesn’t pose risks.
If you take estrogen orestrogen-based contraceptives, vitamin C may increase the risk ofhormonal side effects. This is because vitamin C may slow the rate at whichestrogenleaves your body.
Vitamin C can also increase the absorption of certain drugs, such as:
Vitamin C supplementation can make some medications less effective, including:
This is not a complete list of interactions that may occur with vitamin C. Talk to your healthcare provider and pharmacist before starting vitamin C supplementation or adjusting your intake and let them know about everything you’re taking; this includes prescription and over-the-counter drugs, vitamins, and herbal supplements.
How to Store Vitamin C
Store vitamin C supplements in a closed container, away from exposure to light.
Verywell / Anastasia Tretiak
Sources of Vitamin C and What to Look For
Vitamin C is readily available in your diet, and most people can get the required amounts from food.
Multiple vitamin C supplement formulations are readily available. You can buy them from most stores and websites that sell nutritional supplements.
Food Sources of Vitamin C
It is always best to get your nutrients from food rather than supplements.
Fruits and vegetables, especially citrus fruits, are good sources. Foods naturally rich in vitamin C include:
If you don’t get enough vitamin C from what you eat, a supplement can help get you to the right levels.
Vitamin C Supplements
Vitamin C supplements are available as a single nutrient supplement or combination supplement. You can find them in many forms, such as:
You may also see different types of vitamin C, including:
No one form is more effective than another. Remember to look at the dosages and avoid exceeding the TUL.
Also, pay attention to units of measure. The RDA for vitamin C is in milligrams (mg), but vitamin C labels may list grams (g) or micrograms (mcg).
This ensures purity and that the contents match the label; however, it doesn’t guarantee effectiveness.
The 6 Best Vitamin C Supplements
Summary
Vitamin C supplements have been marketed for many conditions. Ultimately, it’s the best treatment for vitamin C deficiency.
As an antioxidant and anti-inflammatory, vitamin C has been studied for its uses in heart disease prevention, gout, immunity, and more.
It is best to get vitamin C from your food. But if you don’t, a supplement can help you meet your goals. Talk to your healthcare provider before taking supplements.
The right dosage depends on several factors, including age and medical conditions. In addition, vitamin C can interact with certain medications and cause side effects at high levels, so it is important to discuss with your healthcare provider whether supplementation is appropriate for you.
44 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. 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In: Chen Q, Vissers MCM, eds.Vitamin C: New Biochemical and Functional Insights. Boca Raton (FL): CRC Press; 2020.115-135.Holford P, Carr AC, Jovic TH, et al.Vitamin C-an adjunctive therapy for respiratory infection, sepsis and COVID-19.Nutrients. 2020;12(12):3760. doi:10.3390/nu12123760Pullar JM, Carr AC, Vissers MCM.The roles of vitamin C in skin health.Nutrients. 2017;9(8):866. doi:10.3390/nu9080866Nakajima M, Kojiro M, Aso S, et al.Effect of high-dose vitamin C therapy on severe burn patients: a nationwide cohort study.Crit Care. 2019;23(1):407. doi:10.1186/s13054-019-2693-1Harvard University, T.H. 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44 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health Office of Dietary Supplements.Vitamin C.National Institutes of Health, National Center for Complementary and Integrative Health.Antioxidants: in depth.Pizzino G, Irrera N, Cucinotta M, et al.Oxidative stress: harms and benefits for human health.Oxid Med Cell Longev. 2017;2017:8416763. doi:10.1155/2017/8416763Forman HJ, Zhang H.Targeting oxidative stress in disease: promise and limitations of antioxidant therapy.Nat Rev Drug Discov. 2021;20(9):689-709. doi:10.1038/s41573-021-00233-1National Institutes of Health, National Heart, Lung, and Blood Institute.What is atherosclerosis?D’Oria R, Schipani R, Leonardini A, et al.The role of oxidative stress in cardiac disease: from physiological response to injury factor.Oxidative Medicine and Cellular Longevity. 2020:5732956. doi:10.1155/2020/5732956Baradaran A, Nasri H, Rafieian-Kopaei M.Oxidative stress and hypertension: possibility of hypertension therapy with antioxidants.J Res Med Sci. 2014;19(4):358-367.Moser MA, Chun OK.Vitamin C and heart health: a review based on findings from epidemiologic studies.Int J Mol Sci. 2016;17(8):1328. doi:10.3390/ijms17081328Guan Y, Dai P, Wang H.Effects of vitamin C supplementation on essential hypertension: a systematic review and meta-analysis.Medicine. 2020;99(8):e19274. doi:10.1097/MD.0000000000019274MedlinePlus.Hypertensive heart disease.Lee B, Oh SW, Myung SK.Efficacy of vitamin C supplements in prevention of cancer: a meta-analysis of randomized controlled trials.Korean J Fam Med. 2015;36(6):278-285. doi:10.4082/kjfm.2015.36.6.278Böttger F, Vallés-Martí A, Cahn L, Jimenez CR.High-dose intravenous vitamin C, a promising multi-targeting agent in the treatment of cancer.J Exp Clin Cancer Res. 2021;40(1):343. doi:10.1186/s13046-021-02134-yPoljsak B, Milisav I.The role of antioxidants in cancer, friends or foes?Curr Pharm Des. 2018;24(44):5234-5244. doi:10.2174/1381612825666190123112647Centers for Disease Control and Prevention.Gout.Liu XX, Wang XX, Cui LL.Association between oral vitamin C supplementation and serum uric acid: A meta-analysis of randomized controlled trials.Complement Ther Med. 2021;60:102761. doi:10.1016/j.ctim.2021.102761Brzezińska O, Styrzyński F, Makowska J, Walczak K.Role of vitamin C in prophylaxis and treatment of gout-a literature review.Nutrients. 2021;13(2):701. doi:10.3390/nu13020701MedlinePlus.Iron deficiency anemia.Simonson W.Should vitamin C routinely be given with oral iron supplements?Geriatr Nurs. 2019;40(3):327-328. doi:10.1016/j.gerinurse.2019.05.007Li N, Zhao G, Wanling W, Zhang M, Liu W, Chen Q.The efficacy and safety of vitamin C for iron supplementation in adult patients with iron deficiency anemia: a randomized clinical trial.JAMA Netw Open. 2020;3(11):e2023644. doi:10.1001/jamanetworkopen.2020.23644Huijskens MJ, Walczak M, Koller N, et al.Technical advance: ascorbic acid induces development of double-positive T cells from human hematopoietic stem cells in the absence of stromal cells.J Leukoc Biol. 2014;96(6):1165-1175. doi:10.1189/jlb.1TA0214-121RRAhmad SR.Vitamin C for COVID-19 treatment: Have we got enough evidence?Front Nutr. 2022;9:892561. doi:10.3389/fnut.2022.892561Carr AC.Vitamin c in pneumonia and sepsis. In: Chen Q, Vissers MCM, eds.Vitamin C: New Biochemical and Functional Insights. Boca Raton (FL): CRC Press; 2020.115-135.Holford P, Carr AC, Jovic TH, et al.Vitamin C-an adjunctive therapy for respiratory infection, sepsis and COVID-19.Nutrients. 2020;12(12):3760. doi:10.3390/nu12123760Pullar JM, Carr AC, Vissers MCM.The roles of vitamin C in skin health.Nutrients. 2017;9(8):866. doi:10.3390/nu9080866Nakajima M, Kojiro M, Aso S, et al.Effect of high-dose vitamin C therapy on severe burn patients: a nationwide cohort study.Crit Care. 2019;23(1):407. doi:10.1186/s13054-019-2693-1Harvard University, T.H. Chan School of Public Health.Collagen.Ran L, Zhao W, Wang J, et al.Extra dose of vitamin c based on a daily supplementation shortens the common cold: a meta-analysis of 9 randomized controlled trials.BioMed Research International. 2018;2018:1-12.Hemilä H, Chalker E.Vitamin C for preventing and treating the common cold.Cochrane Database Syst Rev. 2013;(1):CD000980. doi:10.1002/14651858.CD000980.pub4Hemilä H, Chalker E.Vitamin C reduces the severity of common colds: a meta-analysis.BMC Public Health. 2023;23(1):2468. doi:10.1186/s12889-023-17229-8Cerullo G, Negro M, Parimbelli M, et al.The long history of vitamin C: From prevention of the common cold to potential aid in the treatment of COVID-19.Front Immunol. 2020; 11:574029. doi:10.3389/fimmu.2020.574029Quidel S, Gómez S, Bravo-Soto G, Ortigoze A.What are the effects of vitamin C on the duration and severity of the common cold?Medwave. 2018;18(5):e7260. doi:10.5867/medwave.2018.06.7260Evans JR, Lawrenson JG.Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration.Cochrane Database Syst Rev. 2023;9(9):CD000254. doi:10.1002/14651858.CD000254.pub5Age-Related Eye Disease Study Research Group.A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS report no. 8.Arch Ophthalmol. 2001;119(10):1417-1436. doi:10.1001/archopht.119.10.1417Zampatti S, Ricci F, Cusumano A, Marsella LT, Novelli G, Giardina E.Review of nutrient actions on age-related macular degeneration.Nutr Res. 2014;34(2):95–105. doi:10.1016/j.nutres.2013.10.011The Cochrane Collaboration.Preventing dementia: do vitamin and mineral supplements have a role?Kocot J, Luchowska-Kocot D, Kiełczykowska M, Musik I, Kurzepa J.Does vitamin C influence neurodegenerative diseases and psychiatric disorders?Nutrients. 2017;9(7):659. doi:10.3390/nu9070659Zhou F, Xie X, Zhang H, Liu T.Effect of antioxidant intake patterns on risks of dementia and cognitive decline.Eur Geriatr Med. 2023;14(1):9-17. doi:10.1007/s41999-022-00720-7Hantikainen E, Lagerros YT, Ye W, et al.Dietary antioxidants and the risk of Parkinson disease. The Swedish National March Cohort.Neurology.2021;96(6):e895-e903. doi:10.1212/WNL.0000000000011373Rowe S, Carr AC.Global vitamin C status and prevalence of deficiency: a cause for concern?Nutrients. 2020;12(7):2008. doi:10.3390/nu12072008National Center for Advancing Translational Sciences. Genetic and Rare Diseases Information Center.Scurvy.Miraj F, Karda IWAM, Abdullah A, Dionysios E.Lessons learned from “the great mimicker disease”: A retrospective study of 18 patients with scurvy.J Child Orthop. 2023;17(6):618-625. doi:10.1177/18632521231213150Marik PE.Is intravenous vitamin C contraindicated in patients with G6PD deficiency?Critical Care. 2019. doi:10.1186/s13054-019-2397-6Martini N.Potion or poison? Vitamin C.J Prim Health Care. 2014;6(3):251. doi:10.1071/HC14251Skelin M, Lucijanić T, Klarić DA, et al.Factors affecting gastrointestinal absorption of levothyroxine: a review. 2017.Clinical Therapeutics. doi:10.1016/j.clinthera.2017.01.005
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Institutes of Health Office of Dietary Supplements.Vitamin C.National Institutes of Health, National Center for Complementary and Integrative Health.Antioxidants: in depth.Pizzino G, Irrera N, Cucinotta M, et al.Oxidative stress: harms and benefits for human health.Oxid Med Cell Longev. 2017;2017:8416763. doi:10.1155/2017/8416763Forman HJ, Zhang H.Targeting oxidative stress in disease: promise and limitations of antioxidant therapy.Nat Rev Drug Discov. 2021;20(9):689-709. doi:10.1038/s41573-021-00233-1National Institutes of Health, National Heart, Lung, and Blood Institute.What is atherosclerosis?D’Oria R, Schipani R, Leonardini A, et al.The role of oxidative stress in cardiac disease: from physiological response to injury factor.Oxidative Medicine and Cellular Longevity. 2020:5732956. doi:10.1155/2020/5732956Baradaran A, Nasri H, Rafieian-Kopaei M.Oxidative stress and hypertension: possibility of hypertension therapy with antioxidants.J Res Med Sci. 2014;19(4):358-367.Moser MA, Chun OK.Vitamin C and heart health: a review based on findings from epidemiologic studies.Int J Mol Sci. 2016;17(8):1328. doi:10.3390/ijms17081328Guan Y, Dai P, Wang H.Effects of vitamin C supplementation on essential hypertension: a systematic review and meta-analysis.Medicine. 2020;99(8):e19274. doi:10.1097/MD.0000000000019274MedlinePlus.Hypertensive heart disease.Lee B, Oh SW, Myung SK.Efficacy of vitamin C supplements in prevention of cancer: a meta-analysis of randomized controlled trials.Korean J Fam Med. 2015;36(6):278-285. doi:10.4082/kjfm.2015.36.6.278Böttger F, Vallés-Martí A, Cahn L, Jimenez CR.High-dose intravenous vitamin C, a promising multi-targeting agent in the treatment of cancer.J Exp Clin Cancer Res. 2021;40(1):343. doi:10.1186/s13046-021-02134-yPoljsak B, Milisav I.The role of antioxidants in cancer, friends or foes?Curr Pharm Des. 2018;24(44):5234-5244. doi:10.2174/1381612825666190123112647Centers for Disease Control and Prevention.Gout.Liu XX, Wang XX, Cui LL.Association between oral vitamin C supplementation and serum uric acid: A meta-analysis of randomized controlled trials.Complement Ther Med. 2021;60:102761. doi:10.1016/j.ctim.2021.102761Brzezińska O, Styrzyński F, Makowska J, Walczak K.Role of vitamin C in prophylaxis and treatment of gout-a literature review.Nutrients. 2021;13(2):701. doi:10.3390/nu13020701MedlinePlus.Iron deficiency anemia.Simonson W.Should vitamin C routinely be given with oral iron supplements?Geriatr Nurs. 2019;40(3):327-328. doi:10.1016/j.gerinurse.2019.05.007Li N, Zhao G, Wanling W, Zhang M, Liu W, Chen Q.The efficacy and safety of vitamin C for iron supplementation in adult patients with iron deficiency anemia: a randomized clinical trial.JAMA Netw Open. 2020;3(11):e2023644. doi:10.1001/jamanetworkopen.2020.23644Huijskens MJ, Walczak M, Koller N, et al.Technical advance: ascorbic acid induces development of double-positive T cells from human hematopoietic stem cells in the absence of stromal cells.J Leukoc Biol. 2014;96(6):1165-1175. doi:10.1189/jlb.1TA0214-121RRAhmad SR.Vitamin C for COVID-19 treatment: Have we got enough evidence?Front Nutr. 2022;9:892561. doi:10.3389/fnut.2022.892561Carr AC.Vitamin c in pneumonia and sepsis. In: Chen Q, Vissers MCM, eds.Vitamin C: New Biochemical and Functional Insights. Boca Raton (FL): CRC Press; 2020.115-135.Holford P, Carr AC, Jovic TH, et al.Vitamin C-an adjunctive therapy for respiratory infection, sepsis and COVID-19.Nutrients. 2020;12(12):3760. doi:10.3390/nu12123760Pullar JM, Carr AC, Vissers MCM.The roles of vitamin C in skin health.Nutrients. 2017;9(8):866. doi:10.3390/nu9080866Nakajima M, Kojiro M, Aso S, et al.Effect of high-dose vitamin C therapy on severe burn patients: a nationwide cohort study.Crit Care. 2019;23(1):407. doi:10.1186/s13054-019-2693-1Harvard University, T.H. Chan School of Public Health.Collagen.Ran L, Zhao W, Wang J, et al.Extra dose of vitamin c based on a daily supplementation shortens the common cold: a meta-analysis of 9 randomized controlled trials.BioMed Research International. 2018;2018:1-12.Hemilä H, Chalker E.Vitamin C for preventing and treating the common cold.Cochrane Database Syst Rev. 2013;(1):CD000980. doi:10.1002/14651858.CD000980.pub4Hemilä H, Chalker E.Vitamin C reduces the severity of common colds: a meta-analysis.BMC Public Health. 2023;23(1):2468. doi:10.1186/s12889-023-17229-8Cerullo G, Negro M, Parimbelli M, et al.The long history of vitamin C: From prevention of the common cold to potential aid in the treatment of COVID-19.Front Immunol. 2020; 11:574029. doi:10.3389/fimmu.2020.574029Quidel S, Gómez S, Bravo-Soto G, Ortigoze A.What are the effects of vitamin C on the duration and severity of the common cold?Medwave. 2018;18(5):e7260. doi:10.5867/medwave.2018.06.7260Evans JR, Lawrenson JG.Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration.Cochrane Database Syst Rev. 2023;9(9):CD000254. doi:10.1002/14651858.CD000254.pub5Age-Related Eye Disease Study Research Group.A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS report no. 8.Arch Ophthalmol. 2001;119(10):1417-1436. doi:10.1001/archopht.119.10.1417Zampatti S, Ricci F, Cusumano A, Marsella LT, Novelli G, Giardina E.Review of nutrient actions on age-related macular degeneration.Nutr Res. 2014;34(2):95–105. doi:10.1016/j.nutres.2013.10.011The Cochrane Collaboration.Preventing dementia: do vitamin and mineral supplements have a role?Kocot J, Luchowska-Kocot D, Kiełczykowska M, Musik I, Kurzepa J.Does vitamin C influence neurodegenerative diseases and psychiatric disorders?Nutrients. 2017;9(7):659. doi:10.3390/nu9070659Zhou F, Xie X, Zhang H, Liu T.Effect of antioxidant intake patterns on risks of dementia and cognitive decline.Eur Geriatr Med. 2023;14(1):9-17. doi:10.1007/s41999-022-00720-7Hantikainen E, Lagerros YT, Ye W, et al.Dietary antioxidants and the risk of Parkinson disease. The Swedish National March Cohort.Neurology.2021;96(6):e895-e903. doi:10.1212/WNL.0000000000011373Rowe S, Carr AC.Global vitamin C status and prevalence of deficiency: a cause for concern?Nutrients. 2020;12(7):2008. doi:10.3390/nu12072008National Center for Advancing Translational Sciences. Genetic and Rare Diseases Information Center.Scurvy.Miraj F, Karda IWAM, Abdullah A, Dionysios E.Lessons learned from “the great mimicker disease”: A retrospective study of 18 patients with scurvy.J Child Orthop. 2023;17(6):618-625. doi:10.1177/18632521231213150Marik PE.Is intravenous vitamin C contraindicated in patients with G6PD deficiency?Critical Care. 2019. doi:10.1186/s13054-019-2397-6Martini N.Potion or poison? Vitamin C.J Prim Health Care. 2014;6(3):251. doi:10.1071/HC14251Skelin M, Lucijanić T, Klarić DA, et al.Factors affecting gastrointestinal absorption of levothyroxine: a review. 2017.Clinical Therapeutics. doi:10.1016/j.clinthera.2017.01.005
National Institutes of Health Office of Dietary Supplements.Vitamin C.
National Institutes of Health, National Center for Complementary and Integrative Health.Antioxidants: in depth.
Pizzino G, Irrera N, Cucinotta M, et al.Oxidative stress: harms and benefits for human health.Oxid Med Cell Longev. 2017;2017:8416763. doi:10.1155/2017/8416763
Forman HJ, Zhang H.Targeting oxidative stress in disease: promise and limitations of antioxidant therapy.Nat Rev Drug Discov. 2021;20(9):689-709. doi:10.1038/s41573-021-00233-1
National Institutes of Health, National Heart, Lung, and Blood Institute.What is atherosclerosis?
D’Oria R, Schipani R, Leonardini A, et al.The role of oxidative stress in cardiac disease: from physiological response to injury factor.Oxidative Medicine and Cellular Longevity. 2020:5732956. doi:10.1155/2020/5732956
Baradaran A, Nasri H, Rafieian-Kopaei M.Oxidative stress and hypertension: possibility of hypertension therapy with antioxidants.J Res Med Sci. 2014;19(4):358-367.
Moser MA, Chun OK.Vitamin C and heart health: a review based on findings from epidemiologic studies.Int J Mol Sci. 2016;17(8):1328. doi:10.3390/ijms17081328
Guan Y, Dai P, Wang H.Effects of vitamin C supplementation on essential hypertension: a systematic review and meta-analysis.Medicine. 2020;99(8):e19274. doi:10.1097/MD.0000000000019274
MedlinePlus.Hypertensive heart disease.
Lee B, Oh SW, Myung SK.Efficacy of vitamin C supplements in prevention of cancer: a meta-analysis of randomized controlled trials.Korean J Fam Med. 2015;36(6):278-285. doi:10.4082/kjfm.2015.36.6.278
Böttger F, Vallés-Martí A, Cahn L, Jimenez CR.High-dose intravenous vitamin C, a promising multi-targeting agent in the treatment of cancer.J Exp Clin Cancer Res. 2021;40(1):343. doi:10.1186/s13046-021-02134-y
Poljsak B, Milisav I.The role of antioxidants in cancer, friends or foes?Curr Pharm Des. 2018;24(44):5234-5244. doi:10.2174/1381612825666190123112647
Centers for Disease Control and Prevention.Gout.
Liu XX, Wang XX, Cui LL.Association between oral vitamin C supplementation and serum uric acid: A meta-analysis of randomized controlled trials.Complement Ther Med. 2021;60:102761. doi:10.1016/j.ctim.2021.102761
Brzezińska O, Styrzyński F, Makowska J, Walczak K.Role of vitamin C in prophylaxis and treatment of gout-a literature review.Nutrients. 2021;13(2):701. doi:10.3390/nu13020701
MedlinePlus.Iron deficiency anemia.
Simonson W.Should vitamin C routinely be given with oral iron supplements?Geriatr Nurs. 2019;40(3):327-328. doi:10.1016/j.gerinurse.2019.05.007
Li N, Zhao G, Wanling W, Zhang M, Liu W, Chen Q.The efficacy and safety of vitamin C for iron supplementation in adult patients with iron deficiency anemia: a randomized clinical trial.JAMA Netw Open. 2020;3(11):e2023644. doi:10.1001/jamanetworkopen.2020.23644
Huijskens MJ, Walczak M, Koller N, et al.Technical advance: ascorbic acid induces development of double-positive T cells from human hematopoietic stem cells in the absence of stromal cells.J Leukoc Biol. 2014;96(6):1165-1175. doi:10.1189/jlb.1TA0214-121RR
Ahmad SR.Vitamin C for COVID-19 treatment: Have we got enough evidence?Front Nutr. 2022;9:892561. doi:10.3389/fnut.2022.892561
Carr AC.Vitamin c in pneumonia and sepsis. In: Chen Q, Vissers MCM, eds.Vitamin C: New Biochemical and Functional Insights. Boca Raton (FL): CRC Press; 2020.115-135.
Holford P, Carr AC, Jovic TH, et al.Vitamin C-an adjunctive therapy for respiratory infection, sepsis and COVID-19.Nutrients. 2020;12(12):3760. doi:10.3390/nu12123760
Pullar JM, Carr AC, Vissers MCM.The roles of vitamin C in skin health.Nutrients. 2017;9(8):866. doi:10.3390/nu9080866
Nakajima M, Kojiro M, Aso S, et al.Effect of high-dose vitamin C therapy on severe burn patients: a nationwide cohort study.Crit Care. 2019;23(1):407. doi:10.1186/s13054-019-2693-1
Harvard University, T.H. Chan School of Public Health.Collagen.
Ran L, Zhao W, Wang J, et al.Extra dose of vitamin c based on a daily supplementation shortens the common cold: a meta-analysis of 9 randomized controlled trials.BioMed Research International. 2018;2018:1-12.
Hemilä H, Chalker E.Vitamin C for preventing and treating the common cold.Cochrane Database Syst Rev. 2013;(1):CD000980. doi:10.1002/14651858.CD000980.pub4
Hemilä H, Chalker E.Vitamin C reduces the severity of common colds: a meta-analysis.BMC Public Health. 2023;23(1):2468. doi:10.1186/s12889-023-17229-8
Cerullo G, Negro M, Parimbelli M, et al.The long history of vitamin C: From prevention of the common cold to potential aid in the treatment of COVID-19.Front Immunol. 2020; 11:574029. doi:10.3389/fimmu.2020.574029
Quidel S, Gómez S, Bravo-Soto G, Ortigoze A.What are the effects of vitamin C on the duration and severity of the common cold?Medwave. 2018;18(5):e7260. doi:10.5867/medwave.2018.06.7260
Evans JR, Lawrenson JG.Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration.Cochrane Database Syst Rev. 2023;9(9):CD000254. doi:10.1002/14651858.CD000254.pub5
Age-Related Eye Disease Study Research Group.A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS report no. 8.Arch Ophthalmol. 2001;119(10):1417-1436. doi:10.1001/archopht.119.10.1417
Zampatti S, Ricci F, Cusumano A, Marsella LT, Novelli G, Giardina E.Review of nutrient actions on age-related macular degeneration.Nutr Res. 2014;34(2):95–105. doi:10.1016/j.nutres.2013.10.011
The Cochrane Collaboration.Preventing dementia: do vitamin and mineral supplements have a role?
Kocot J, Luchowska-Kocot D, Kiełczykowska M, Musik I, Kurzepa J.Does vitamin C influence neurodegenerative diseases and psychiatric disorders?Nutrients. 2017;9(7):659. doi:10.3390/nu9070659
Zhou F, Xie X, Zhang H, Liu T.Effect of antioxidant intake patterns on risks of dementia and cognitive decline.Eur Geriatr Med. 2023;14(1):9-17. doi:10.1007/s41999-022-00720-7
Hantikainen E, Lagerros YT, Ye W, et al.Dietary antioxidants and the risk of Parkinson disease. The Swedish National March Cohort.Neurology.2021;96(6):e895-e903. doi:10.1212/WNL.0000000000011373
Rowe S, Carr AC.Global vitamin C status and prevalence of deficiency: a cause for concern?Nutrients. 2020;12(7):2008. doi:10.3390/nu12072008
National Center for Advancing Translational Sciences. Genetic and Rare Diseases Information Center.Scurvy.
Miraj F, Karda IWAM, Abdullah A, Dionysios E.Lessons learned from “the great mimicker disease”: A retrospective study of 18 patients with scurvy.J Child Orthop. 2023;17(6):618-625. doi:10.1177/18632521231213150
Marik PE.Is intravenous vitamin C contraindicated in patients with G6PD deficiency?Critical Care. 2019. doi:10.1186/s13054-019-2397-6
Martini N.Potion or poison? Vitamin C.J Prim Health Care. 2014;6(3):251. doi:10.1071/HC14251
Skelin M, Lucijanić T, Klarić DA, et al.Factors affecting gastrointestinal absorption of levothyroxine: a review. 2017.Clinical Therapeutics. doi:10.1016/j.clinthera.2017.01.005
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