Module 8 - Water-Soluble Vitamins Flashcards
When and by who, was the term vitamins formed?
1912, by Casimir Funk, made the term “vitamine”, “vita” = necessary for life, “amine” = nitrogen containing substance
Why was the term “vitamine” modified to “vitamin”?
Not all are amines
What does the term vitamin mean?
complex organic compound that regulates metabolic processes
What do vitamins promote?
normal functioning, growth, and maintenance
What are the similarites and differences between vitamins and macronutrients?
Similarities: Organic (carbon containing)
Differences: daily needs of vitamins are small, individual units instead of long chains, not a source of energy but play crucial role in reactions that extract energy from macros (coenzymes!)
What is a coenzyme?
coenzyme attach to inactive enzyme allowing enzyme to become active
What are sources of vitamins?
plants, animals, fungi, bacteria and supplements
Is it necessary to consume 100% of every vitamin every day?
No
What place in the body can produce vitamins?
Gut microbiota can produce biotin and vitamin K that can be absorbed to an extent
What does “bioavailability of vitamins” refer to?
Amount actually available for use by the body
What factors affect bioavailability of vitamins?
Life stage and nutrient status
Changes to normal GI transit time
Health conditions
Food processing and preparation
Sources of vitamin
Where are vitamins primarily absorbed?
Small intestine
Are vitamins fully absorbed?
No, but small intestine can increase absorption if necessary by body
What facilitates absorption of vitamins?
Fat digestion (Bile)
How can you enhance vitamin absoprtion?
By adding small amounts of fat (adding butter to broccoli)
What are the Water-Soluble Vitamins and Fat Soluble Vitamins?
Water-soluble: B vitamins and vitamin C
Fat-soluble: vitamin A, D, E, K (ADEK)
The difference in solubility of fat soluble and water soluble vitamins affects…
the bodies absorption, transport and storage of the vitamin
How are fat-soluble vitamins absorbed?
intestinal cells absorb fat-soluble vitamins (along with fat), packaged into lipoproteins, enter lymph system, reach liver where they are stored/repackaged for delivery to other tissues
Where do excess fat-soluble vitamins go?
Accumulate in liver and fatty tissues (reserves can last for weeks or months)
How are water-soluble vitamins absorbed?
Intestinal cells absorb water-soluble vitamins directly into the bloodstream
What is the difference in storage quantity between fat soluble and water soluble vitamins?
Fat soluble vitamins are stored in large amounts and reserves can last for weeks or months Water-soluble vitamins are not stored in large amounts, needed regularly from diet
What happens to excess water-soluble vitamins?
kidneys can excrete in urine
Steps of Vitamin Absorption
- Chewing breaks food apart, helping to release vitamins
- Digestion of food in stomach releases vitamins, some niacin absorbed
- Gallbladder releases bile, helps absorb fat-soluble vitamins
- Pancreas secretes digestive enzymes that aid in release of vitamins from food
- in small intestine, fat soluble vitamins are incorporated into micelles and absorbed into mucosal cells, then packaged into chylomicrons, which enter the lymph before passing into blood and eventually liver
- Water soluble vitamins are absorbed from the small intestine directly into blood
- In large intestine, bacteria synthesize small amount of vitamins, some of which are absorbed
Explain role of mouth in vitamin absorption
Chewing breaks food apart, helping to release vitamins
Explain role of stomach in vitamin absorption
Digestion of food in stomach releases vitamins, some niacin absorbed
Explain the role of Gallbladder in vitamin absorption
Gallbladder releases bile, which emulsifies fat and helps absorb fat soluble vitamins
Explain the role of the Pancreas in vitamin absorption
Pancreas secretes digestive enzymes that aid in release of vitamins from food
Explain fat soluble vitamin absorption in the small intestine
fat soluble vitamins are incorporated into micelles and absorbed into mucosal cells by simple diffusion, then packaged into chylomicrons, which enter the lymph before passing into blood and eventually liver
Explain water-soluble vitamin absorption in the small intestine
Water-soluble vitamins are absorbed from the small intestine directly into the blood
Explain the role of large intestine in vitamin absorption
Gut microbiota synthesizes small amounts of vitamins, some which are absorbed
What can lead to reduced vitamin absorption and lead to deficiencies?
Diseases that affect GI tract (eg. cystic fibrosis - unable to digest fat properly; often develop deficiencies of fat-soluble vitamins)
How can vitamin absorption be increased through medicine?
Large oral doses or injections enable small amounts of vitamins to be absorbed
What is enrichment of vitamins?
addition of vitamins that were taken our during refinement; helps protect from deficiencies of thiamin, riboflavin, niacin, folate, iron
What is NOT added back in enrichment process?
Vitamin E, B6, Magnesium, fiber, other micronutrients that were present in unrefined grain
What is fortification of vitamins?
addition of vitamins that weren’t originally there; some concerns over excessive amounts of some vitamins while reducing intake of others
What is Vitamin Toxicity?
When cells are saturated with a vitamin, continuing to take vitamin can produce toxicity disorder (exposure to excess micronutrient or its by-products can damage cells)
What can occur due to vitamin toxicity?
Liver damage when intake level of some vitamins is toxic
Why does Vitamin Deficiency occur?
inadequate diets or conditions that increase body’s requirement for vitamins (e.g., reduced intestinal absorption)
What types of vitamins are usually consumed less than recommended amounts?
Fat-soluble vitamins (A,D,E,K)
What populations are at risk for vitamin deficiencies?
alcoholism, older adults, hospitalized patients, people consuming low fat, people with intestinal conditions that affect absorption
How many B vitamins are there?
8
Name all 8 B-vitamins
Thiamin (B1)
Riboflavin (B2)
Niacin (B3)
Pantothenic Acid (B5)
Biotin (B7)
Vitamin B6
Folate (B9)
Vitamin B12
What is Vitamin B1 also called
Thiamin
What are the functions of Vitamin B1?
- Part of coenzyme TPP (needed to make acetyl CoA, necessary for breakdown of CHO)
- Needed for synthesis of neurotransmitters
Thiamin found in __ amounts in __ foods
small
many
Deficiency of Thiamin can lead to Beriberi, describe it
body systems begin deteriorating; deficient glucose metabolism
What are signs of Beriberi (caused by Thiamin - Vitamin B1 deficiency)
digestive: diarrhea
muscle: wasting and pain
nerve: disrupts coordination, “pins and needles”
Deficiency of Thiamin can lead to Wernicke-Korsakoff Syndrome, describe it
Degenerative brain disorder associated with thiamin deficiency, primarily caused by alcohol-induced malnutrition b/c alcohol reduces thiamin absorption and increases its excretion
Signs of Wernicke-Korsakoff Syndrome (caused by Thiamin - Vitamin B1 deficiency)
abnormal eye movements, staggering gait, distorted thought process
How can you resolve Wernicke-Korsakoff Syndrome?
eliminate alcohol and obtain thiamin injections, without prompt treatment, permanent disability or death
What are food sources of Thiamin (Vitamin B1)
grain products, pork and ham
What is Vitamin B2 also called?
Riboflavin