Vitamin C

The naming of vitamins began with Funk’s isolated concentrate. The molecule present

here was called vitamin B, since it cured Beri beri disease.

Following this, vitamins were name alphabetically: vitamin A was discovered in 1913-1914, and then in chronological order, vitamin C, vitamin D which could cure rickets disease, and vitamin E which was important

to fertility.

The later discovery of a vitamin required for blood clotting led to the naming of vitamin K

where the K denotes koagulation.

Background Background

Vitamin C is ascorbic acidVitamin C is ascorbic acid The human body cannot synthesize The human body cannot synthesize

vitamin Cvitamin C Vitamin C is a water soluble vitaminVitamin C is a water soluble vitamin In 1928 vitamin C was isolatedIn 1928 vitamin C was isolated In 1933 its structure was determinedIn 1933 its structure was determined

Vitamin C (ascorbic acid)Vitamin C (ascorbic acid)

Antioxidant, strong reducing Antioxidant, strong reducing agentagent

Collagen synthesis, tissue repair, Collagen synthesis, tissue repair, bones & teeth, immune system, bones & teeth, immune system, iron absorptioniron absorption

Cannot be made by human body Cannot be made by human body though animals can though animals can biosynthesize from glucosebiosynthesize from glucose

Found in citrus fruits, cruciferous Found in citrus fruits, cruciferous veggies, tomatoes, dark green veggies, tomatoes, dark green leafy, berries, mangos, melonsleafy, berries, mangos, melons

Degraded by cookingDegraded by cooking Deficiency causes scurvy, Deficiency causes scurvy,

anemia, depression, infection, anemia, depression, infection, tooth/gum problems, muscle tooth/gum problems, muscle deterioration, fragile bones, poor deterioration, fragile bones, poor wound healingwound healing

Alternative Names•Ascorbic acid;•Dehydroascorbic acid

Where Does It Come From?Where Does It Come From?•Kiwi•Oranges•Sweet potatoes•Lemons•Tomatoes•Strawberries•Turnip Greens•Broccoli•Red peppers•Cantaloupe•White potatoes•Papaya•Blueberries•Mango and many others

ChemistryChemistry

Vitamin C is a weak acid, called Ascorbic acid or its salts “Ascorbate”.

It is the L-enantiomer of Ascorbic acid.

The D-enantiomer shows no biological activity.

Commercial vitamin C is often a mix of Ascorbic acid, Sodium ascorbate and/or other Ascorbates.

OO

OHHO

H

OH

HO

How do other nutrients interact with vitamin C ?

•Supplemental intake of vitamin C at gram-level doses can interfere with copper metabolism.

•Conversely, vitamin C can significantly enhance iron uptake and metabolism, even at food-level amounts.

•Vitamin C also has important interactions with other vitamins. Excessive intake of vitamin A, for example, is less toxic to the body when vitamin C is readily available.

•Vitamin C is involved in the regeneration of vitamin E, and these two vitamins appear to work together in their antioxidant effect.

•The vast majority of animals and plants are able to synthesize vitamin C, through a sequence of enzyme driven steps, which convert monosaccharide to vitamin C.

•In plants, this is accomplished through the conversion of mannose or galactose to ascorbic acid.  

•In some animals, glucose needed to produce ascorbate in the liver (in mammals and perching birds) is extracted from glycogen; ascorbate synthesis is a glycogenolysis-dependent process.

•In reptiles and birds the biosynthesis is carried out in the kidneys

VITAMIN-C IN THE WILD

Why Do We Need It?Why Do We Need It?

Vitamin C helps us:•Grow•Repair broken tissue when we get hurt•Make collagen – heal cuts and bones•Boost immunity

The four most noted functions that vitamin The four most noted functions that vitamin C affect are:C affect are:

1.1. ANTIOXIDANT ACTIVITYANTIOXIDANT ACTIVITY When vitamin C is digested, it When vitamin C is digested, it

becomes a water soluble antioxidant. becomes a water soluble antioxidant. Because it is in the water soluble state, Because it is in the water soluble state, vitamin C can directly affect the free vitamin C can directly affect the free radicals in the body. Free radicals are radicals in the body. Free radicals are molecules located in the body which are molecules located in the body which are highly reactive, and known for causing highly reactive, and known for causing tissue damage. They are also notoriously tissue damage. They are also notoriously known for inducing oxidative damage to known for inducing oxidative damage to the inner body, advancing the aging the inner body, advancing the aging process, and can also cause cancer.process, and can also cause cancer.

2.2. Collagen SynthesisCollagen SynthesisCollagen is the essential part of connective Collagen is the essential part of connective tissue. Connective tissue is needed to keep the tissue. Connective tissue is needed to keep the body together, and is the very framework of the body together, and is the very framework of the body - the skin, bones, teeth, blood vessels, body - the skin, bones, teeth, blood vessels, cartilage, tendons and ligaments - all rely on cartilage, tendons and ligaments - all rely on collagen.collagen.

3.3. The Cardiovascular SystemThe Cardiovascular System Furthermore, vitamin C is vital for the Furthermore, vitamin C is vital for the

cardiovascular system. When the body's cardiovascular system. When the body's arteries become clogged, there isn't enough arteries become clogged, there isn't enough blood flow to the heart which results in a heart blood flow to the heart which results in a heart attack. Vitamin C's antioxidant properties are attack. Vitamin C's antioxidant properties are absorbed into the blood stream, and can absorbed into the blood stream, and can actually repress the accumulation of arterial actually repress the accumulation of arterial blood.blood.

4 The Immune System4 The Immune System Finally, vitamin C impacts the immune Finally, vitamin C impacts the immune

system. The immune system main operation is to system. The immune system main operation is to protect the body from foreign substances or protect the body from foreign substances or toxins. For the immune system to function toxins. For the immune system to function correctly, vitamin C is a must. Vitamin C is correctly, vitamin C is a must. Vitamin C is extremely important in this function because it is extremely important in this function because it is involved with T-cells and white blood cells. The involved with T-cells and white blood cells. The white blood cells function is basically to monitor white blood cells function is basically to monitor various disease conditions. Because vitamin C various disease conditions. Because vitamin C boosts the white blood cell count, an individual boosts the white blood cell count, an individual who consumes high doses of vitamin C has a less who consumes high doses of vitamin C has a less likely chance of contracting diseases.likely chance of contracting diseases.

What is Its Role in The Body?What is Its Role in The Body?

AntioxidantAntioxidant Decreasing the risk Decreasing the risk

of certain of certain conditionsconditions

Strengthen the Strengthen the immune systemimmune system

Ascorbic acid is absorbed in the body by both active transport and simple diffusion

Sodium-Dependent Active Transport—Sodium-Ascorbate Co-Transporters (SVCTs) and Hexose transporters (GLUTs)—are the two transporters required for absorption.

Ascorbate concentrations over renal re-absorption threshold pass freely into the urine and are excreted.

ABSORPTION & EXCRETION

At high dietary doses (corresponding to several hundred mg/day in humans) ascorbate is accumulated in the body until the plasma levels reach the renal resorption threshold, which is about 1.5 mg/dL in men and 1.3 mg/dL in women.

Concentrations in the plasma larger than this value (thought to represent body saturation) are rapidly excreted in the urine with a half-life of about 30 minutes.

Concentrations less than this threshold amount are actively retained by the kidneys, and the excretion half-life for the remainder of the vitamin C store in the body thus increases greatly, with the half-life lengthening as the body stores are depleted.

This half-life rises until it is as long as 83 days by the onset of the first symptoms of scurvy

Recommendation for Dietary Recommendation for Dietary IntakeIntake

Ages 4 to 8 : 15 mg/day

Ages 9 to 13: 25 mg/day

Females 14 to 18: 65 mg/day

Males 14 to 18: 75 mg/day

Females 19 < : 75 mg/day

Males 19 < : 90 mg/day

Bleeding gumsRough and dry skinSlow healing when hurtEasy bruisingNosebleedsWeight gainIncreased chance of infectionLoss of teeth

Some signs of deficiency:

Vitamin C DeficiencyVitamin C Deficiency Deficiency disease is called Deficiency disease is called

scurvyscurvy Deficiency SymptomsDeficiency Symptoms

Anemia – small cell typeAnemia – small cell type Atherosclerotic plaques and Atherosclerotic plaques and

pinpoint hemorrhagespinpoint hemorrhages Bone fragility and joint painBone fragility and joint pain Poor wound healing and Poor wound healing and

frequent infectionsfrequent infections Bleeding gums and loosened Bleeding gums and loosened

teethteeth Muscle degeneration and pain, Muscle degeneration and pain,

hysteria, and depressionhysteria, and depression Rough skin and blotchy bruisesRough skin and blotchy bruises

Diagnosis of ScurvyDiagnosis of Scurvy Fasting blood ascorbic acid levels:

levels below 0.10 mg/dL are considered deficient. levels of 0.10-0.19 mg/dL are considered low. levels of 0.2 mg/dL or greater are acceptable levels greater than 0.6 mg/dL likely rule out

scurvy.

White blood cell ascorbic acid concentration is considered a more accurate measurement of vitamin C nutritional status: with a level of zero suggesting scurvy. 0-7 mg/dL suggesting deficiency. 8-15 mg/dL considered low. 15 mg/dL or greater is adequate vitamin C status.

TREATMENTTREATMENT

Scurvy can be treated by eating food Scurvy can be treated by eating food containing vitamin C (such as containing vitamin C (such as oranges, papaya, strawberries, oranges, papaya, strawberries, lemon), tablets with vitamin Clemon), tablets with vitamin C

THERAPEUTIC USESTHERAPEUTIC USES

• Cardiovascular diseases

• Cataracts

• Diabetes Mellitus

• Cancer prevention

• Common cold

• Lead toxicity

How do cooking, storage, or processing affect vitamin C ?

Vitamin C is highly sensitive to air, water, and temperature.

About 25% of the vitamin C in vegetables can be lost simply by blanching (boiling or steaming the food for a few minutes). This same degree of loss occurs in the freezing and unthawing of vegetables and fruits.

Cooking of vegetables and fruits for longer periods of time (10-20 minutes) can result in a loss of over one half the total vitamin C content.

When fruits and vegetables are canned and then reheated, only 1/3 of the original vitamin C content may be left.

Consumption of vitamin C-rich foods in their fresh, raw form is the best way to maximize vitamin C intake

Vitamin C ToxicityVitamin C Toxicity Toxicity SymptomsToxicity Symptoms

Nausea, abdominal cramps, diarrhea, Nausea, abdominal cramps, diarrhea, headache, fatigue and insomniaheadache, fatigue and insomnia

Hot flashes and rashesHot flashes and rashes Interference with medical tests, creating a Interference with medical tests, creating a

false positive or a false negativefalse positive or a false negative Aggravation of gout symptoms, urinary tract Aggravation of gout symptoms, urinary tract

infections, and kidney stonesinfections, and kidney stones Upper level for adults: 2000 mg/dayUpper level for adults: 2000 mg/day

Cease vitamin C intake & Treatment of underlying condition

TREATMENT

More Interesting Facts About Vitamin C:

English sailors were called limeys because they sucked on limes to prevent scurvy.

Inuit people have very few fresh fruits and vegetables, but they do not get scurvy. That's because the traditional sea foods they eat

such as seal meat and Arctic char are high in vitamin C.

Ascorbic acid as a food additive helps preserve colours and flavours in canned food.

Vitamin C and coffee can be used to develop black and white photo film.

It is the most widely researched nutrient on the Internet.Many people think oranges are the food highest in vitamin C, but

there are others with higher levels including red bell peppers, papaya, broccoli.