Vitamin C

(Ascorbic acid)

Chapter 14: Vitamin C.

Department of Human Physiology & Biochemistry (Dr. Ravind Yadav)
 SPECIFIC LEARNING OBJECTIVE

• On completion of study of this chapter, the student

WILL be able to:

Discuss Vitamin C in detail.

Illustrate Hypervitaminosis.

Discuss diseases caused due to Vitamin- C deficiency.

 INTRODUCTION
Ascorbic acid is a water soluble
antioxidant functions as a reducing
agent. Required for normal collagen
formation, as well as in bone and dentin
formation and wound healing process.
 STRUCTURE AND
FORMULA
Vitamin C is also known as
ascorbic acid. It is a six-
carbon sugar derivative. Most
animals can synthesize
ascorbic acid. But humans
cannot synthesize ascorbic
acid, due to lack of the
enzyme gluconolactone
oxidase which is required for
the synthesis of ascorbic acid.
Thus, humans have a dietary
requirement of ascorbic acid.
 ACTIVE FORM

• Ascorbic acid itself is the active

form of VITAMIN C.
 SOURCES
The main dietary sources of
vitamin Care leafy vegetables
and fruits, especially citrus fruits,
strawberries, tomatoes,

spinach and potatoes.

Cereals contain no vitamin C.

Animal tissues and dairy

products are very poor sources.
RECOMMENDED DIETARY
ALLOWANCE (RDA)
• To provide antioxidant protection, a Recommended
Dietary Allowance (RDA) of 90 mg/day for adult men,
75 mg/day for adult women and 100 mg/ day during
pregnancy and lactation is set based on the vitamin C
intake to maintain near-maximal neutrophil concentration
with minimal urinary excretion of ascorbate.
 FUNCTIONS
1. VITAMIN C helps in cross- linking of collagen.
2. VITAMIN C plays the role of coenzyme in
hydroxylation of proline and lysine for the the
synthesis of collagen. It is helpful in
maintenance of normal connective tissue and
wound healing process.
 FUNCTIONS
3. Helps in formation of bone.

4. IRON and HEMOGLOBIN Metabolism.

Ascorbic acid enhances iron absorption by keeping
it in the ferrous form .
 FUNCTIONS
5. It has Antioxidant property. So is able to
trap free radicals and prevents unnecessary
oxidation in the body.
6. TRYPTOPHAN Metabolism
Vit-C is essential for hydroxylation of
tryptophan to hydrotryptophan in the
 FUNCTIONS
7. FOLIC ACID metabolism. Vit-C is needed in the
formation of THF. In association with the THF
ascorbic acid is involved in the maturation of
erythrocytes.

8. Synthesis of Corticosteroid hormones.

Vit-C is necessary for hydroxylation reaction in
 FUNCTIONS
9. IMMUNOLOGICAL Functions.
Vit-C enhances the synthesis of
immunoglobulins.

10. Helps in TYROSINE Metabolism.

 THERAPEUTIC USES
Use of vitamin C in preventing cold and cancers
has not been scientifically supported. Although
the incidence of common cold is not reduced by
vitamin C, the duration of cold episodes and
severity of symptoms can be decreased. Vitamin
C may act reacting with free radicals.
 DEFICIENCY
MANIFESTATIONS
1. Rough, Bumpy skin (Keratosis pilaris)
Vitamin C plays a key role in collagen production, a protein that
is abundant in connective tissues like skin, hair, joints, bones and
blood vessels.
When vitamin C levels are low, a skin condition known as
keratosis pilaris can develop.
In this condition, bumpy “chicken skin” forms on the back of the
upper arms, thighs or buttocks due to a buildup of keratin protein
inside the pores.
 DEFICIENCY
MANIFESTATIONS
2. Corkscrew-Shaped Body Hair

Vitamin C deficiency can also cause hair to grow in

bent or coiled shapes due to defects that develop in
the protein structure of hair as it grows.
Corkscrew-shaped hair is one of the hallmark signs of
vitamin C deficiency but may not be obvious, as these
damaged hairs are more likely to break off or fall out.
Hair abnormalities often resolve within one month of
treatment with adequate amounts of vitamin C.
 DEFICIENCY
MANIFESTATIONS
3. Bleeding Gums and Tooth Loss
(SCURVY)

Red, swollen, bleeding gums are another

common sign of vitamin C deficiency.
Without adequate vitamin C, gum tissue
becomes weakened and inflamed and blood
vessels bleed more easily.
In advanced stages of vitamin C deficiency,
gums may even appear purple and rotten.
Eventually, teeth can fall out due to unhealthy
gums and weak dentin, the calcified inner
layer of teeth.
 DEFICIENCY
MANIFESTATIONS
4. Poor Immunity
Studies show that vitamin C accumulates inside various types
of immune cells to help them combat infection and destroy
disease-causing pathogens.
Vitamin C deficiency is associated with poor immunity and a
higher risk of infection, including serious illnesses like
pneumonia.
In fact, many people with scurvy, a disease caused by
vitamin C deficiency, eventually die of infection due to
their poorly functioning immune systems.
 DEFICIENCY
MANIFESTATIONS
5. Persistent Iron Deficiency Anemia

Vitamin C and iron deficiency anemia often occur together.

Signs of iron deficiency anemia include paleness, fatigue, trouble
breathing during exercise, dry skin and hair, headache and spoon-
shaped fingernails.
Low levels of vitamin C may contribute to iron deficiency anemia by
reducing the absorption of iron from plant-based sources.
Vitamin C deficiency also increases the risk of excessive bleeding,
which can contribute to anemia.
If iron deficiency anemia persists for a long time with no obvious
causes, it may be wise to check your vitamin C levels.
 DEFICIENCY
MANIFESTATIONS
6. Chronic Inflammation and Oxidative Stress
Vitamin C is one of the body’s most important water-soluble antioxidants.
It helps prevent cellular damage by neutralizing free radicals that can cause
oxidative stress and inflammation in the body.
Oxidative stress and inflammation have been linked to many chronic
illnesses, including heart disease and diabetes, so reducing levels is likely
beneficial.
Low intakes of vitamin C have been linked to higher levels of inflammation
and oxidative stress, as well as an increased risk of heart disease.
One study found that adults with the lowest blood levels of vitamin C were
nearly 40% more likely to develop heart failure within 15 years than those
with the highest blood levels, even though they were not deficient in
vitamin C.
 DEFICIENCY
MANIFESTATIONS
7. Weak Bones

Vitamin C deficiency can also affect bone health. In fact, low

intake has been linked to increased risk of fracture and
osteoporosis.
Research has found that vitamin C plays a critical role in bone
formation, so a deficiency can increase the rate of bone loss.
Children’s skeletons may be especially affected by vitamin C
deficiency, as they are still growing and developing.
 DEFICIENCY
MANIFESTATIONS
8. Easy Bruising

WHY ?
 DEFICIENCY
MANIFESTATIONS
Bruising occurs when blood vessels under the skin
rupture, causing blood to leak into the surrounding areas.
Easy bruising is a common sign of vitamin C deficiency
since poor collagen production causes weak blood
vessels.
Deficiency-related bruises may cover large areas of the
body or appear as small, purple dots under the skin.
 DEFICIENCY
MANIFESTATIONS
9. Spoon-Shaped Fingernails With Red Spots or Lines
Spoon-shaped nails are characterized by their concave shape and
often thin and brittle.
They are more commonly associated with iron deficiency anemia
but have also been linked to vitamin C.
Red spots or vertical lines in the nail bed, known as splinter
hemorrhage, may also appear during vitamin C deficiency due to
weakened blood vessels that rupture easily.
While the visual appearance of fingernails and toenails may help
determine the likelihood of vitamin C deficiency, note that it’s not
considered diagnostic.
 Thank You!
Prepared by-
Ayush Billade (14)
Jiya Deshmukh (19)
Muskan Chaudhary (53)

Department of Human Physiology & Biochemistry (Dr. Ravind Yadav)