This document discusses vitamin B1 (thiamine). It begins by classifying B1 as a water-soluble vitamin that is part of the B-complex group. It then describes B1's functions in energy metabolism and as a coenzyme. Sources of B1 are also listed, including pork, liver, beans and enriched grains. The document concludes by covering absorption in the small intestine, deficiencies that can arise from inadequate intake such as beriberi, and issues related to toxicity.

2.  Classification Of B1 Vitamin
 Functions
 Sources
 Absorption & Metabolism
 Deficiencies
 Toxicity
OVERVIEW

3. CLASSIFICATION
Water soluble
B – Vitamins
Vitamin C
 Dissolve in water easily
 Needed in minute amount
 Pass easily through the
bloodstream
 Remain in the body for a
short time
 Are needed on a daily basis
B – Complex (1-13)
B1 – Thiamine
B2 – Riboflavin
B3 – Niacin
B6 – Pyridoxine
B9 – Folate
B12 – Cobalamine

4.  Provide energy indirectly
 Are needed for generating energy (ATP) from macronutrients
 B-complex vitamins are particularly important in assisting energy metabolism
 Often function as coenzymes (molecule combining with enzyme to help release
energy from the vitamin)
VITAMINS ENERGY METABOLISM

6. Physical Characteristics
 White , water soluble crystalline solid
 Complex structure : includes an amino (-NH2) group and a hydroxyl group
 Its amine part forms salts with acids (e.g thiamine reacts with HCL to form
thiamine hydrochloride to fortify flour)
B1 – THIAMIN

7. Physical Characteristics
 Its hydroxyl part forms esters with acids (e.g thiamine pyrophoshate
coenzyme)
B1 – THIAMIN

8.  Coenzyme thiamin pyrophosphate -TPP is required for
series of metabolic reactions to release energy from
carbohydrate mainly, branched-chain amino acids & F.A’s
 Required for normal growth in children for general health
 Assists in production of DNA and RNA and synthesis of
neurotransmitters for the proper functioning and
maintenance of the nerves (i.e. muscle coordination and a healthy
nervous system)
B1 – THIAMIN FUNCTIONS

9. Good sources:
 Pork & pork products,
 All meat ;- Liver
 Beans,
 Sunflower seeds,
 Cereals
 Enriched and whole-
grains
 Dry beans and peas
 Bread, flour*
 Avocado
 Yeast
 Milk
SOURCES

11.  Occurs in the upper (B12*) and lower small intestine (duodenum
and jejunum)
 Absorbed directly into the portal vein and transported to the
liver
 some B1 is stored in the liver, heart, and kidneys.
 Most excess thiamine is eliminated through the kidneys in urine;
some seems to be excreted in the sweat as well.
 When other B vitamins become deficient, particularly folic acid
and vitamin B12, absorption of vitamin B1 is compromised.
ABSORPTION

14. Water-Soluble
Vitamins
Fat-Soluble
Vitamins
Absorbed in the Small Intestine Small Intestine
Hydrophobic or
Hydrophilic
Hydrophilic Hydrophobic
Absorbed into the Blood Lymph
Stored in the body Not Generally Yes
Can build up and
become toxic
Not Generally Yes
Need to consume
daily
Yes No

15. usually found in
pyrophosphate form
active site
METABOLISM
 Essential in energy-yielding metabolism, and especially the
metabolism of carbohydrates
 Thiamine pyrophosphate is an essential coenzymes that
catalyze the oxidative decarboxylation of α-keto acids to
form an acylated coenzyme A (acyl CoA).
 These include pyruvate dehydrogenase , α -keto glutarate
dehydrogenase and branched-chain α-keto acid
dehydrogenase.

16.  These three enzymes operate by a similar catalytic
mechanism.
 Catalyzes decarboxylation of a-keto acids, a feature of
primary metabolism
• e.g. pyruvic acid → acetaldehyde in glycolysis
• pyruvic acid → acetyl-CoA (Fig.2.15 p23 Dewick)

 Helps metabolize carbohydrates
 Supports nervous system
 Deficiency causes beriberi (neurological disorder)
METABOLISM

17. Reasons for deficiency of B1 :
• people with alcoholism. With increased alcoholic intake, thiamin is poorly
absorbed and easily excreted by the body.
• poor dietary intake
• Pregnancy, due to loss of appetite, vomiting
Signs and symptoms of B1deficiency :
1. Depression, irritability, difficulty in concentration, defective memory,
anxiety.
2. Retarded growth in children.
3. Nerves becomes inflamed and painful (neurititis), muscles becomes weak,
reflexes are reduced
4. Severe deficiency leads to the disease BERI-BERI.
DEFICIENCIES

18. Severe Deficiency: Beriberi Symptoms :-
 a condition that involves poor appetite, weight loss, fatigue, enlargement
of heart with rapid heartbeat and heart failure (Wet Beri-Beri).
 causes confusion, muscle wasting, nerve degeneration & damage, where
the nervous system is badly affected and may lead to partial paralysis and
muscular weakness (Dry Beri-Beri).
 Usually only seen in the United States in babies who are fed formula that
isn't supplemented with Vitamin B1
 seen in people who drink large amounts of alcohol as they develop
neuropathic syndrome affecting legs, balance and cognitive function. (need
vitamin B1 supplements).
 Dramatic: loss of memory-making capacity (Korsakoff’s psychosis)
together with acute paralysis of the muscles which moves the eyes ;full
syndrome known as:- Weirnicke’s encephalopathy*.
DEFICIENCIES

20. We have not been able to find any reports of toxicity related to dietary
intake of vitamin B1. When supply of the vitamin exceeds our needs, we
urinate out the excess. Reflecting the lack of evidence of toxicity, The
National Academy of Sciences has not chosen to establish a Tolerable
Upper Intake Level (UL) for vitamin B1.
TOXICITY

21.  It can be taken only if strongly prescribed by the doctor, that is in
case where a patient is suffering from a chronic disease.
 Otherwise there is no need as it is possible to obtain all necessary
vitamins and minerals by following a healthy diet.
 Sometimes healthy people choose to take multivitamins as
“insurance” to make sure they obtain all the vitamins and minerals
they need each day. And statistics states that Americans spend
billions of dollars on vitamin and mineral supplements each year.
 For those requiring supplements:
(Note: Vitamin tablets should be taken with a meal or snack to increase
absorption. Otherwise the vitamins or minerals will likely be excreted in
the urine and wasted)
SUPPLEMENTATION OF VITAMIN B1
 Supplements often occur in the form of a
tablet, which usually contains synthetic
forms of single or mixed vitamins and
minerals.
 supplement of vitamin B1 is very limited
in our existence as it is found commonly
in the form of B-Complex.

22. Ways to retain the vitamin content of food when cooking:-
 Refrigerate fresh produce
 Keep milk and grains away from strong light
 Avoid washing food too much e.g rice*, fruits and vegetables during food
preparation and storage
 If you take vitamin supplements, store them at room temperature in a dry place
that's free of moisture
 Cook food for a short time.
 Use cooking methods such as: Steaming, microwaving, and stir-frying to
preserve maximum vitamins.
 To prevent leaching of vitamins or minerals, do not soak vegetables. Instead,
rinse them thoroughly and drain.
STORAGE OF VITAMIN B1

23.  Water soluble vitamins dissolve in
water but not in fat, and are
generally not stored in the body.
 Essential to life, growth, and body
maintenance.
 Come from food or are produced
within the body.
 Food should be the source of our
nutrients.
 Many of the B vitamins, such as
thiamin, riboflavin, and niacin, are
found in enriched and whole-grain
products.
SUMMARY
 Fat soluble vitamins are soluble in
fat but not in water, and they can be
stored in the body’s fat tissue.
 essential to life, growth, and body
maintenance.
 come from food or are produced
within the body.
 Food should be the source of our
nutrients.
 The fat-soluble vitamins have both
plant and animal sources.

24.  Vitamin B12 is found only in animal
products.
 Consuming too many can be harmful
to health.
 Whole food and fortified food can
contribute to total water soluble
vitamin consumption.
 Toxic amounts of each are usually
the result of taking high-dose
supplements every day.
SUMMARY
 For example, vitamin A comes from
dairy products and the precursor
beta-carotene comes from orange
vegetables like squash and carrots.
 Consuming too many can be
harmful to health.
 Whole food and fortified food can
contribute to total fat soluble
vitamin consumption.
 Toxic amounts of each are usually
the result of taking high-dose
supplements every day.

25. 1. Food and Nutrition by Anita Tull.
Oxford university press 1996
2. Fox and Cameron’s Food Science
Nutrition & Health 7th edition by
Micheal E.J. Lean. Oxford university
press 2006
1. To insert
SOURCES
1. To insert1. To insert

26. THANK YOU VERY MUCH FOR
YOUR ATTENTION
Author: Nirma Banee
Suggestions most
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