The document discusses vitamin C deficiency (scurvy) and its associated disorders. It provides information on the functions, sources, recommended dietary allowances and symptoms of vitamin C deficiency. Key points include: - Vitamin C is an essential water-soluble antioxidant vitamin that helps form collagen and supports immune function. Deficiency can cause bleeding gums and fragile blood vessels. - Good dietary sources include citrus fruits, berries, peppers and leafy greens. Cooking can destroy up to 70% of vitamin C. - Symptoms of deficiency include fatigue, joint pain and hemorrhaging of the skin and mucus membranes. Long term deficiency can lead to bone fractures and poor wound healing. Infants are at

1. Vitamin C Deficiency
Disorders
Nutritional Deficiency Disorders
R O S H I N A R A B A I L
L E C T U R E R , G O V E R N M E N T C O L L E G E W O M E N U N I V E R S I T Y , F A I S A L A B A D , P A K I S T A N
M . P H I L H U M A N N U T R I T I O N A N D D I E T E T I C S
F O R M E R D I E T I T I A N C M H O K A R A C A N T T . & S H I F A I N T . H O S P I T A L I S L A M A B A D
ROSHINA RABAIL 1

2. ROSHINA RABAIL 2

3. Vitamin C
oVitamin C (L- ascorbic acid) structurally resembles a
monosaccharide sugar (Glucose).
oEssential micronutrient; Water soluble vitamin, that acts as
an antioxidant, electron donor.
oVery less stable to heat and light; 70 percentage lost in the
process of cooking.
oMost animals & plants can synthesize ascorbic acid from
glucose.
ROSHINA RABAIL 3

4. Sources
oFoods high in vitamin C include the
following.
oCitrus fruits, especially grapefruits and
lemons, limes, oranges, peaches,
strawberries, bananas.
oVegetables, including broccoli, green
peppers, tomatoes, potatoes, and
cabbage.

5. Functions of Vitamin C
oOxidation of tyrosine and phenylalanine
oFormation of hydroxyproline,
oPreventing depolymerization of collagen
oImportant in hemopoiesis
oSynthesis of collagen, carnitine, hormone and amino acids
oEssential for wound healing
oFacilitates recovery from burns
oSupports immune function
oFacilitates the absorption of iron.
ROSHINA RABAIL 5

6. ROSHINA RABAIL 6

7. Functions of Vitamin C
oCollagen synthesis:
o Ascorbic acid is necessary for the post
transilational hydroxylation of proline &
lysine Residues. Hydroxy proline & hydroxy
lysine form cross links in collagen- gives
tensile strength to fibers. This process is
necessary for the normal production of
supporting tissues like osteoid, collagen,
and intercellular cement substances of
capillaries
ROSHINA RABAIL 7

8. Functions of Vitamin C
oIron metabolism:
oVit C reduces Ferric to Ferrous to help absorbed from
intestine.
oHemoglobin metabolism:
o Reconversion of met-hemoglobin to hemoglobin.
oFolic acid metabolism:
oHelps the enzyme folate reductase to reduce folic acid to
tetrahydrofolic acid. Thus helps in maturation of RBC.
ROSHINA RABAIL 8

9. Functions of Vitamin C
oTyrosine metabolism:
oOxydation of
parahydroxyphenylpyruvate
to homogenitisic acid.
oTryptophan metabolism:
oHydroxylation of tryptophan
to 5-hydroxyl tryptophan-
formation of serotonin.
ROSHINA RABAIL 9

10. oSteroid synthesis:
oHas some role in adrenal steroidogenesis.
Vit C is present in adrenal cortex-
depleted by ACTH stimulation.
oStrengthen Immune system:
oStimulates phagocytic action of WBC.
oEye Health:
oVit C is concentrated in the lens of eye.
Regular intake of vit C reduces risk of
cataract formation.
oAntioxidant property:
oAbility to scavenge free radicals directly.
Participate in metaboluc reactions that
regenerate antioxidant form of vit E.
ROSHINA RABAIL 10
Functions of Vit. C

11. RDA
ROSHINA RABAIL 11

12. Dietary factors determining vitamin C status
Factor Summary and Comments
Dietary intake Dietary intake, particularly fruit intake, correlates with improved vitamin C status and
decreased prevalence of deficiency; is dependent on the amount consumed,
frequency of consumption, and type of food consumed as the vitamin C content of
food varies. High dietary fat and sugar intake are associated with
decreased vitamin C intake and status.
Staple foods Staple foods such as grains (e.g., rice, millet, wheat/couscous, corn) and some starchy
roots and tubers are low in vitamin C; populations who consume these staples can have
lower overall vitamin C intake.
Traditional
cooking
practices
Through boiling or steaming, water-soluble vitamins may be leached from food and
prolonged cooking of food can destroy vitamin C; this could lead to decreased vitamin C
status in certain social or ethnic groups. Drying of leafy vegetables also decreases
water-soluble vitamins.
Supplement use Supplement users have significantly higher vitamin C status and negligible prevalence
of deficiency. Non-users have a 2–3 fold odds ratio of insucient and deficient vitamin C
status. ROSHINA RABAIL 12

13. Vitamin C Deficiency
oCalled Scurvy and its
symptoms generally develop
after 3 months of severe or
total vit C deficiency.
oGross deficiency of vitamin C is
characterized by:
obone diseases in growing children
ohemorrhages
ohealing defects in both children &
adults.
ROSHINA RABAIL 13

14. Vitamin C Deficiency
oFormation of intercellular cement substances in connective tissues,
bones, and dentin is defective, resulting in weakened capillaries with
subsequent hemorrhage and defects in bone and related structures.
oHemorrhaging is a hallmark feature of scurvy and can occur in any
organ. Hair follicles are one of the common sites of cutaneous
bleeding.
oBone tissue formation becomes impaired, which, in children, causes
bone lesions and poor bone growth.
ROSHINA RABAIL 14

15. Who are at Risk?
oBabies who are fed only cow's milk during the first year of life are at risk.
oAlcoholism
oElderly/ Retired people who live alone
oThose who eat primarily fast food
oCigarette smokers require increased intake of vitamin C because of lower
vitamin C absorption and increased catabolism.
oPregnant and lactating women and those with thyrotoxicosis require increased
intake of vitamin C because of increased utilization.
oEconomically disadvantaged persons tend to not purchase foods high in
vitamin C.
ROSHINA RABAIL 15

16. oRefugees who are dependent on external suppliers for their food and have
limited access to fresh fruits and vegetables.
oPeople with anorexia nervosa or anorexia from other diseases such as AIDS or
cancer are at increased risk of vitamin C deficiency.
oPeople with type 1 diabetes have increased vitamin C requirements, as do those
on hemodialysis and peritoneal dialysis.
oBecause vitamin C is absorbed in the small intestine, people with disease of the
small intestine such as Crohn’s, Whipple, and celiac disease are at risk.
oIron overload disorders may lead to renal vitamin C wasting.
ROSHINA RABAIL 16
Who are at Risk?

17. Symptoms of Vitamin C Deficiency
oEarly symptoms: discomfort, fatigue and lethargy.
oAfter 1-3 months: patients develop shortness of breath and bone
pain.
oLong Term Outcomes:
oMyalgias (muscular aches) due to reduced carnitine.
oBruising easily & bleeding from weakened blood vessels, connective
tissue & bones due to collagen loss.
oDry mouth, dry eyes, Hair & teeth loss
oGingivitis: gums become painful, swollen & spongy, friability,
bleeding, and infection with loose teeth
ROSHINA RABAIL 17

18. oSkin:
oroughness, easy bruising and petechiae, Perifollicular
hemorrhages (See figure), purpura, and ecchymoses are seen
most commonly on the legs and buttocks where hydrostatic
pressure is the greatest. Poor wound healing and breakdown
of old scars may be seen.
oHair:
oAlopecia may occur secondary to reduced disulfide bonding.
oNails:
oSplinter hemorrhages may occur.
ROSHINA RABAIL 18
Symptoms of Vitamin C Deficiency

19. oEye:
oScleral icterus (late, probably secondary to hemolysis); and pale
conjunctiva are seen.
oConjunctival hemorrhage: Bleeding into the periorbital area,
eyelids, and retrobulbar space also can be seen.
oChest and cardiovascular:
oScorbutic rosary (ie, sternum sinks inward/beaded appearance of
anterior ends of ribs) may occur in children.
oHigh-output heart failure due to anemia can be observed.
oBleeding into the myocardium and pericardial space has been
reported.
ROSHINA RABAIL 19
Symptoms of Vitamin C Deficiency

20. oExtremities:
oFractures, dislocations, and tenderness of bones are common in children.
oBleeding into muscles and joints may be seen.
oEdema may occur late in the disease.
oGastrointestinal: Loss of weight secondary to anorexia is common.
oIn the late stages, jaundice, generalized edema, oliguria,
neuropathy, fever, and convulsions can be seen.
oVital signs: Hypotension may be observed late in the disease. This
may be due to an inability of the resistance vessels to constrict in
response to adrenergic stimuli.
ROSHINA RABAIL 20
Symptoms of Vitamin C Deficiency

21. Infantile scurvy (Barlow's disease)
oInfantile scurvy is characterized by gross irritability, excessive crying and
tenderness to touch, more so in the lower limbs.
oScurvy occurs usually in infants between the age of 6 months to 2 years. No age
is a bar, however.
oThe infant adopts the so-called "frogposition”. The posture of the lower limbs
gives an impression as though these are paralyzed.
oInfants have pain when they move & lose their appetite.
oInfants do not gain weight as they normally do.
oIn infants & children bone growth is impaired & bleeding & anemia may occur.
oIn infants between 6 to 12 months of age diet should be supplemented with
vitamin C sources.
ROSHINA RABAIL 21

22. oIn bones, deficiency results in failure of osteoblast to form the intercellular
ground substance osteoid
oThe resulting scorbutic bone is weak & fractures easily
oHemorrhage into joint cavity lead to painful swelling of the joint
oMicrocytic hypochromic anemia is seen with Poikilocytosis (red blood cells of
varying sizes ) & anisocytosis (red blood cells of varying shapes).
oReason for anemia may be:
oloss of blood by hemorrhage
odecreased iron absorption
odecreased tetra hydro folic acid THFA
ROSHINA RABAIL 22
Infantile scurvy (Barlow's disease)

23. Diagnosis
oA plasma or leukocyte vitamin C level can confirm clinical diagnosis.
oScurvy occurs at levels generally less than 0.1 mg/dL.
oSymptoms occur at levels below 2.5 mg/L, which is considered deficiency.
oLevels of 2.5-5 mg/L indicate depletion.
oLevels can be low in patients who have tuberculosis, rheumatic fever, or other
chronic illnesses; those who smoke cigarettes; and patients on oral contraceptive
drugs.
oCapillary fragility can be checked by inflating a blood pressure cuff and looking for
petechiae on the forearm. Bleeding time, clotting time and Prothrombin are
estimated to rule out other bleeding disorders
ROSHINA RABAIL 23

24. Treatment/management
o It consists in giving a dose of 500 mg of vitamin C followed by a daily dose of
100 to 300 mg for several weeks. Oral administration is good enough.
o Or patients should take ascorbic acid at 100 mg 3-5 times a day until total of 4 g
is reached, and then they should decrease intake to 100 mg daily.
oDivided doses are better to be given because intestinal absorption is limited to
100 mg at one time.
oParenteral doses are necessary in those with gastrointestinal malabsorption.
ROSHINA RABAIL 24

25. References
oVitamin C Deficiency by Namrata; Biochemistry for medics.
oCarr A. C. and Rowe S. (2020) Factors Aecting Vitamin C Status and Prevalence of Deficiency: A
Global Health Perspective. Nutrients 2020, 12, 1963; doi:10.3390/nu12071963
ROSHINA RABAIL 25