At the end of this lecture, the student should be able to: Describe how coenzymes enhance the activities of enzymes. For each of the eight B-complex vitamins, describe their primary functions and their food sources. Describe the association between folate, vitamin B12, and vascular disease. Identify at least two minerals that function as coenzymes in energy metabolism. Discuss the role that iron plays in oxygen transport. Distinguish between iron-deficiency anemia, pernicious anemia, and macrocytic anemia.

1. Lecture 12: Nutrition Involved
in Metabolism and Blood Health
DR. SHARIFAH WAJIHAH
WAFA
sharifahwajihah@unisza.edu.my

2. Course Learning Outcomes
• At the end of this lecture, the student should be able
to:
1. Describe how coenzymes enhance the activities of
enzymes.
2. For each of the eight B-complex vitamins, describe
their primary functions and their food sources.
3. Describe the association between folate, vitamin B12,
and vascular disease.
4. Identify at least two minerals that function as
coenzymes in energy metabolism.
5. Discuss the role that iron plays in oxygen transport.
6. Distinguish between iron-deficiency anemia,
pernicious anemia, and macrocytic anemia.

3. Vitamins and Metabolism
• Vitamins and minerals
– Are required for proper metabolism
– Do not directly provide energy
– Are necessary for obtaining energy from the
macronutrients
– Often function as coenzymes

4. Vitamins and Metabolism
• Enzymes: a protein that accelerates the rate of
a chemical reaction.
– Enzymes are required for all metabolic reactions
• Coenzymes: a molecule that combines with an
enzyme to activate it.
– Some metabolic reactions require coenzymes

5. Vitamins and Metabolism
Figure 10.1

6. Vitamins and Metabolism
Figure 10.2

7. B-complex Vitamins
• The B-complex vitamins are especially
important for energy metabolism.
• The B-complex vitamins include
-thiamin (B1) -folate
-riboflavin (B2) -vitamin B12
-niacin -pantothenic acid
-vitamin B6 -biotin

8. B-complex Vitamins: Thiamin (Vitamin
B1)
• Coenzyme thiamin
pyrophosphate is required for
carbohydrate metabolism
• Coenzyme for the metabolism
of some fatty acids
• Enriched foods, whole grains,
and pork are good sources
• Beriberi: deficiency of thiamin
resulting in muscle wasting
and nerve damage, heart
failure

9. B-complex Vitamins:
Riboflavin (Vitamin B2)
• Part of coenzymes involved
in oxidation-reduction
reactions
• Part of the antioxidant
enzyme glutathione
peroxidase
• Milk is a good source of
riboflavin
• Ariboflavinosis: riboflavin
deficiency; sore throat,
swollen mucous
membranes

10. B-complex Vitamins: Niacin
• Nicotinamide and nicotinic acid
• Coenzyme assists with the
metabolism of carbohydrates
and fatty acids
• Good sources: meat, fish,
poultry, enriched bread
products
• Toxicity can result from
supplements
• Pellagra: severe niacin
deficiency
• 4 Ds: dermatitis, diarrhea,
dementia, and death

11. B-complex Vitamins:
Vitamin B6 (Pyridoxine)
• Group of six related compounds
• Part of a coenzyme for more than 100 enzymes,
amino acid metabolism, neurotransmitter, and
heme synthesis
• Good sources: enriched cereals, meat, fish,
poultry, starchy vegetables
• Toxicity from supplements can result in nerve
damage and skin lesions
• Deficiency: anemia, elevated levels of
homocysteine

12. B-complex Vitamins: Folate
• Involved in DNA synthesis, amino acid
metabolism, red blood cell synthesis
• Critical for cell division of very early embryos
• Good sources: ready-to-eat cereals, enriched
bread products
• Toxicity can mask vitamin B12 deficiency
• Deficiency: macrocytic anemia

13. Neural Tube Defects
• A woman’s need for folate dramatically
increases during pregnancy.
• Folate is required for cell division and proper
formation of the neural tube.
– The neural tube develops into the brain and spinal
cord

14. Neural Tube Defects
• The increased need for folate is critical very
early (first 4 weeks) in pregnancy, frequently
before a woman knows she is pregnant.
• All women capable of becoming pregnant
should consume an extra 400 µg/day of folate.

15. Spina Bifida

16. Folate Deficiency: Anemia
• Anemia means “without blood”; any
condition of low hemoglobin levels
• There are many types and causes of anemia
• Anemia “without blood” can be caused by a
severe folate deficiency

17. Macrocytic Anemia
• Caused by a severe folate deficiency
• Results in enlarged red blood cells carrying
insufficient hemoglobin
• Shows common symptoms of anemia
including weakness, fatigue, difficulty
concentrating, irritability, headache, shortness
of breath

18. B-complex Vitamins:
Vitamin B12 (Cobalamin)
• Part of coenzymes for blood formation
• Required for nerve functioning
• Required for homocysteine breakdown
• Found only in animal-based foods
• Deficiency results in anemia, low energy,
fatigue, shortness of breath, and can lead to
pernicious anemia

19. Pernicious Anemia
• Pernicious means causing great harm or fatal
• Vitamin B12 deficiency
• Due to low acid production in the stomach or
lack of gastric intrinsic factor production
• Also occurs in people who consume very little
vitamin B12 in their diet
• Symptoms are pale skin, reduced energy,
fatigue, neurological symptoms

20. B-complex Vitamins:
Vitamin B12 (Cobalamin)
• Deficiency is due to insufficient intake or
inability to absorb the vitamin
• Absorption requires: intrinsic factor and low
stomach pH
• Lack of intrinsic factor production can occur
• Atrophic gastritis results in inadequate
stomach acid production
• Vegans are at risk for deficiency

21. Vascular Disease
• Folate and vitamin B12 are required for the
breakdown of the amino acid homocysteine.
• Low folate, vitamin B12, and vitamin B6 intake may
cause an increased level of homocysteine.
• High homocysteine levels are associated with
greater risk of cardiovascular and cerebrovascular
disease.

22. Vascular Disease and Homocysteine
Figure 10.8

23. B-complex Vitamins:
Pantothenic Acid
• Component of coenzymes for fatty acid
metabolism
• Required for building new fatty acids
• Good sources: chicken, beef, egg yolk,
potatoes, oat cereals, tomato products
• No toxicity from excess pantothenic acid
• Deficiency is very rare

24. B-complex Vitamins: Biotin
• Part of coenzymes involved in metabolism of
carbohydrates, fat, and proteins
• Important for gluconeogenesis
• Biotin content has been determined for very few
foods
• Deficiency symptoms include hair thinning, loss
of hair color, red rash on face
• Deficiency is very rare

25. Choline
• Choline is a vitamin-like substance.
– Assists in homocysteine metabolism
– Accelerates the synthesis of acetylcholine, a
neurotransmitter
– Good sources: milk, liver, eggs, peanuts
– Deficiency can lead to fat accumulation in the liver
– Toxicity can result from supplements

26. Iodine
• Iodine is a trace mineral.
– Critical for the synthesis of thyroid hormones
– Thyroid hormones regulate body temperature,
growth, and resting metabolic rate
– Good sources: saltwater fish, shrimp, iodized salt,
milk and dairy products

27. Iodine
• Excess iodine
– Blocks synthesis of thyroid hormones
– Thyroid tries to make more hormones
– Results in goiter: enlarged thyroid
• Iodine deficiency
– Results in hypothyroidism and goiter
– Cretinism: mental retardation from iodine
deficiency during embryonic development

28. Chromium
• Chromium is a trace mineral.
– Assists insulin as it transports glucose from the
blood into the cells
– Plays a role in immune function and growth
– There is very little chromium in the body
– Good sources: mushrooms, prunes, dark
chocolate, nuts, whole grains
– Chromium deficiency inhibits glucose absorption
by body cells

29. Manganese
• Manganese is a trace mineral.
– Coenzyme involved in energy metabolism
– Part of the antioxidant enzyme superoxide
dismutase
– Good sources: whole-grain foods, brown rice,
pineapple, pine nuts, okra, spinach
– Toxicity impairs the nervous system causing
spasms and tremors

30. Sulfur
• Sulfur is a major mineral.
– Component of thiamin and biotin
– Stabilizes protein structure
– Required for detoxification of alcohol and drugs by
the liver
– Found in two amino acids
– Requirement for sulfur is met from the protein in
our diets

31. Blood: Iron, Vit. K, Zinc &
Copper
• Blood is the only fluid tissue in the body.
• Functions
– Transport of oxygen and nutrients to cells
– Removal of wastes products from cells

32. Components of Blood
• Erythrocytes: red blood cells
– Transport oxygen through the body
• Leukocytes: white blood cells of the immune
system
• Platelets: cell fragments that assist in blood
clotting
• Plasma: the fluid portion of the blood

33. Blood
Figure 10.12

34. Vitamin K
• Vitamin K is a fat-soluble vitamin.
– Coenzyme for the synthesis of proteins involved in
blood clotting
– Healthful intestinal bacteria produce some vitamin
K
– Good sources: green leafy vegetables
– Deficiencies can result from diseases that disturb
absorption of fats
– Newborns are given vitamin K at birth

35. Iron
• Iron is a trace mineral.
• Functions of iron
– A component of the protein hemoglobin which
carries oxygen in erythrocytes
– A component of myoglobin which carries oxygen
in muscle cells
– A coenzyme involved in the metabolism of
carbohydrates, fats, and proteins

36. Iron
• Iron can be stored in the body as ferritin or
homosiderin.
– Storage is usually in the liver, bone marrow,
intestinal mucosa, and spleen
• Two types of iron are found in foods
– Heme iron—found in animal based foods and
more absorbable
– Non-heme iron—not easily absorbed, iron not
part of hemoglobin or myoglobin

37. Iron
• Recommended intake
– RDA varies based on age and gender
– 8 mg/day for adult men
– 27 mg/day for pregnant women
• Sources of iron
– Meat, poultry, fish, clams, oysters, enriched
cereals and breads
– Meat factor and vitamin C enhance absorption

38. Iron
• What if you consume too much iron?
– Iron overdose is the most common cause of
poisoning deaths in children
– Toxicity symptoms: nausea, vomiting, diarrhea,
dizziness, confusion
– Delayed treatment of iron toxicity can result in
severe damage to the heart, central nervous
system, liver, kidneys
– Hemochromatosis—excessive iron absorption

39. Iron
• What if you don’t consume enough iron?
– Iron deficiency is the most common nutrient
deficiency in the world
– High-risk people include infants, young children,
preadolescent girls, premenopausal women, and
pregnant women
– There are three stages of iron deficiency

40. Iron
Figure 10.15

41. Iron-Deficient Anemia
• Iron deficiency results in small red blood cells
that do not carry enough hemoglobin
• Symptoms are fatigue, pale skin, impaired
work performance, depressed immune
function, impaired memory

42. Zinc
• Zinc is a trace mineral.
• Functions of zinc
– Cofactor for hemoglobin production
– Part of superoxide dismutase antioxidant enzyme
system
– Development and function of immune system
– Growth
– Assists in energy metabolism

43. Zinc
• Recommended intake
– RDA is 8 mg/day for women
– 11 mg/day for men
• Sources of zinc
– Red meats, some seafood, whole grains, enriched
grains and cereals

44. Zinc
• What if you consume too much zinc?
– Toxicity can occur from supplements
– Symptoms are intestinal pain, cramps, nausea,
vomiting, loss of appetite
• What if you don’t consume enough zinc?
– Deficiencies are uncommon in the United States
– Symptoms are growth retardation, diarrhea,
delayed sexual maturation

45. Copper
• Copper is a trace mineral.
• Functions of copper
– Cofactor for energy metabolism
– Coenzyme that assists in collagen production
– Part of superoxide dismutase antioxidant enzyme
system
– Required for iron transport

46. Copper
• Recommended intake
– RDA for adults is 900 µg/day
• Sources of copper
– Organ meats, seafood, nuts, seeds, whole-grain
foods

47. Copper
• What if you consume too much copper?
– Toxicity in not well studied in humans
– Symptoms are intestinal pain, cramps, nausea,
vomiting, liver damage
• What if you don’t consume enough copper?
– Copper deficiency is rare
– Symptoms are anemia, reduced white blood cells,
osteoporosis in children

48. THANK YOU!