Vitamin C

Ascorbic acid.

A water-soluble vitamin that is necessary for normal growth and development.

An essential nutrient that functions as an antioxidant, immunomodulator,  and cofactor for numerous enzymes.

Regular and adequate dietary consumption is essential.

The absorption of vitamin C takes place in the ileum.

Blood concentrations of vitamin C are regulated by renal excretion.

Forms an important protein used to make skin, tendons, ligaments, and blood vessels

Heal wounds and forms scar tissue

Repairs and maintains cartilage, bones, and teeth.

Disruption in collagen information from vitamin C deficiency causes microfractures in bone, perifollicular hemorrhages, ecchymoses,  hemarthroses, petechiae, and gingival bleeding.

An antioxidant that provides electrons needed for reducing molecular oxygen.

Acts as a cofactor by reducing transition of metal ions in the active sites of specific biosynthetic and regulatory metalloenzymes.

Its antioxidant capabilities stabilize vitamin E, folic acid, and iron.

Vitamin C facilitates the absorption of non-heme iron and  may protect against oxidation of tetrahydrofolate and result in decreased folate levels.


Vitamin C deficiency can lead to iron and folate deficiencies.

Low levels within red blood cells may cause a low-grade hemolysis.

It is a required cofactor in neurotransmitter synthesis.

The body is not able to make vitamin C on its own.

Ascorbic acid is needed for a variety of biosynthetic pathways.

Vitamin C accelerates hydroxylation and amidation reactions.

Vitamin C is required for hydroxylation of proline residues on procollagen molecules supporting the triple-helix structure of collagen that underpins the integrity of skin, blood vessels, mucous membranes, and bone.

Not stored.High-dose ascorbic acid supplements is associated with dose-dependent twofold increase in kidney stone formation in men.

Supplements or vitamin C-rich foods do not reduce the risk of getting the common cold, although people who take vitamin C supplements regularly might have slightly shorter colds or somewhat milder symptoms.

Ingesting vitamin C supplement after a cold starts does not appear to be helpful.

All fruits and vegetables contain some amount of vitamin C.

Vitamin C is required to make the building blocks for collagen.

Ascorbic acid is required for the conversion of the procollagen to collagen by oxidizing proline residues to hydroxyproline.

Procollagen is  modified by the addition of hydroxyl groups to the amino acids proline and lysine. 


Its later glycosylation results in the formation of the triple helix structure of collagen. 


The hydroxylase enzymes that perform these reactions require vitamin C as a cofactor, a long-term deficiency in this vitamin results in impaired collagen synthesis and scurvy.


Vitamin C is a co-factor for enzymes involved in the biosynthesis of carnitine, which plays in essential role in the release of energy through beta oxidation by facilitating the transport of fatty acids into mitochondria.

Impaired carnitine synthesis may account for the weakness, fatigue, and muscle cramping that occurs in patients with the scurvy.

Fruits with the highest sources of vitamin C include: Cantaloupe, Citrus fruits and juices, Kiwi, Mango,Papaya,Pineapple, Strawberries, raspberries, blueberries, cranberries, and Watermelon

Vegetables with the highest sources of vitamin C include: Broccoli, brussels sprouts, cauliflower, green peppers, red peppers, spinach, potatoes, tomatoes, , tomato juice and squash.

Uncooked raw vegetables and fruits have the highest vitamin C content.

Cooking, microwaving and steaming Vitamin C rich foods and storing foods for a long period time can reduce vitamin C content.

High doses of grated 2000 mg per day are not recommended because such doses can lead to gastrointestinal upset and diarrhea.

Hypovitaminosis C can lead to: Anemia, bleeding gums, impaired ability to fight infection, impaired wound healing, dry and splitting hairs, easy bruisability, epistaxis, dry and scaly skin, weakened tooth enamel, and scurvy.

Gingivitis is a hallmark finding a vitamin C deficiency.

Vitamin C is an important coenzyme in collagen production and faulty collagen synthesis leads to gingivitis, as well as to fragile blood vessels prone to hemorrhage.

Vitamin C requirements depends on your age and gender.

Other factors, such as pregnancy and illnesses, are also important.

Dietary Recommendation Intakes for vitamin C:


0 – 6 months: 40 milligrams/day (mg/day)

7 – 12 months: 50 mg/day


1 – 3 years: 15 mg/day

4 – 8 years: 25 mg/day

9 – 13 years: 45 mg/day


Girls 14 – 18 years: 65 mg/day

Boys 14 – 18 years: 75 mg/day


Men age 19 and older: 90 mg/day

Women age 19 year and older: 75 mg/day

Smokers and those who are around secondhand smoke: should increase their daily amount of vitamin C an additional 35 mg per day.

Smokers have increased oxidative stress, and ascorbic acid is an antioxidant, and therefore increased intake is required.

Vitamin C has a crucial role in the synthesis of catecholamines.

Vitamin C increases glucocorticoid receptor sensitivity, allowing increase cellular uptake of glucocorticoids.

Vitamin C antioxidant properties are implicated in maintaining the red cells cytoskeleton proteins beta-spectrin, required for the structure and integrity of the cell.

The loss of  beta-spectrin can contribute to hemolysis in patients with vitamin C deficiency.

Vitamin C functions as a moderator of neurotransmitter synthesis and release,  it is suggested that psychiatric symptoms caused by scurvy precede the physical manifestations.

High dose vitamin C results in oxalate as a breakdown product, which can accumulate renally and lead to acute kidney injury: to facilitate this insoluble metabolite, thiamine is needed for conversion into a water soluble byproduct.

Various health conditions or dietary pecularities may be associated with inadequate Vitamin C intake and include: the elderly, lower socioeconomic groups, alcoholics, the homeless, the mentally ill, patients with AIDS, and malabsorption syndrome.

Vitamin C plasma concentrations are less than 11 mmol per liter commonly in patients with sepsis.

In addition certain illnesses and conditions may be associated with a drop in Vitamin C levels or have greater requirements due to oxidative stress and include: surgical and trauma patients, those with septic shock, critically ill and burn patients.

In patients with sepsis for septic shock, treatment with IV vitamin C, thiamine, and hydrocortisone revealed no differences in mortality compared to a control group with hydrocortisone alone: the length of stay in the ICU  was significantly reduced.
In adults with sepsis receiving vasopressor therapy in the ICU, those who received intravenous vitamin C had a higher risk of death of persistent organ dysfunction at 28 days in those who received placebo (LOVIT investigators).

Groups at risk for developing vitamin C deficiency include: patients with gastrointestinal disease such as colitis, patients with cancer receiving chemotherapy, patients with alcohol use disorder, and patients with psychiatric disorders.

In hospitalized patients with Covid-19 vitamin C had low probability of improving the primary composite outcome of organ support and free days in hospital survival.

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