Vitamins, Minerals, and WaterMicronutrients

Fluid and Electrolytes Balance.

Chapter 8, 9,10BIOL1400

Dr. Mohamad H. Termos

Vitamins

• Essential organic (carbon containing) substances

• Needed in small amounts

• For normal function, growth and maintenance

• They are not energy yielding molecules

Vitamins

Vitamins can be classified into;

1- Water soluble vitamins: such as vitamin C and the B vitamins.

2- Fat soluble vitamins: such as vitamins A, D, E and K.

VitaminsVitamins are needed in the food

because many of them can't be synthesized in the human body.

Exceptions include:- Vitamin A can be synthesized

from plant pigments- Vitamin D can be synthesized

by skin in the presence of sunlight

- Vitamin K can be synthesized by gut bacteria to some extent

Vitamin Toxicity

• Fat-soluble vitamins can accumulate in the body and have toxic effects

• Toxicities of vitamin A are observed most frequently, with consumption as little as 3x human needs

• Vitamin E, Niacin, vitamin B-6, and vitamin C can become toxic when 15-100 times the amount needed is consumed, usually from supplementation

The fat-soluble vitamins – A, D, E, and K

• Absorption of fat soluble vitamins– Absorbed with dietary fat– Special carriers in the bloodstream– Storage in the liver and adipose tissue– 40% to 90% are absorbed when fat

absorption is efficient– Diseases affecting fat absorption, some

medications and laxatives can negatively affect fat soluble vitamin absorption

Vitamin AVitamin A is found in foods in

different forms- Retinoids are preformed

vitamin A only found in animal foods

- Plants contain pigments called carotenoids (provitamin A) which can be turned into vitamin A

Vitamin A: Functions

Vision- Night vision: retinal (form

of vit. A) allows eyes to adjust from bright to dim light.

- Xeropthalmia: dry eye, cells of cornea lose ability to produce mucus which can eventually lead to blindness

- Deficiency is second leading cause of blindness worldwide

Vision (cont.)- Macular degeneration: - Macula of eye contains

carotenoids.- High consumption of these

carotenoids decreases risk of macular degeneration

- Carotenoids may also decrease risk of cataracts

Vitamin A- functions (cont.)- Health of other cells- Growth, development,

and reproduction- Cardiovascular disease

prevention– Carotenoids are

antioxidants– 5 fruits and veggies a

day can decrease risk

• Cancer prevention• Vitamin A analogs used

for acne treatment.

Vitamin A sources and needs - Preformed: Liver, fish,

fortified milk, yogurt and eggs

- Provitamin A: Dark green and orange vegetables and fruits also tomatoes

- Consuming high amounts of marine oils can lead to toxicity

- RDA (Recommended Dietary Allowance): 700 to 900 micrograms

- Daily Value is 1000 micrograms

Vitamin A sources and needs

• Upper level of vitamin A (The highest tolerable level)

– Upper level is 3000 micrograms of preformed vitamin A per day for adult.

– Can lead to fetal malformations, spontaneous abortions, and liver toxicity

– Carotenoids are not toxic

Vitamin D

- Also considered a hormone

- Skin cells can synthesize Vit D using sunlight, 90% comes from sun

- Experts recommend exposing hands, face and arms to the sun for 5-10 minutes, 3 - 5 times per week

Vitamin D: Functions

Regulates calcium and bone metabolism

- Regulates calcium and phosphorus absorption

- Regulates deposition of calcium and phosphorus in bone

Vitamin-D DeficiencyRickets - Vit. D deficiency in

children causes bowed legs

Osteomalacia- Bones become porous

and weak and break easily

- Aging decreases Vit D production in skin by about 70%

Vitamin DDietary sources and

needs

- Mostly in fortified milk and yogurt, fatty fish and fortified cereals

- Also found in eggs and butter.

- AI (Adequate Intake): 5 micrograms per day, higher for older adults

Vitamin D: Upper Level

- 50 micrograms per day

- Causes over-absorption of calcium and calcium deposits in kidneys

- Weakness, loss of appetite, diarrhea, vomiting, and increased urine also symptoms

- Not from excessive sun exposure

Vitamin E - Antioxidant- Resides in cell membranes- Stops free-radicals from

damaging components of the cell membranes and DNA

- Aids in the formation of red blood

- Helps maintain nervous tissue and immune function

Vitamin E: Food sources and needs- Plant oils, cereals, eggs,

and nuts

- Animal fat has almost no Vit E

- Adequate intake = 15 milligram per day

Vitamin E - Upper level is 1000 mg of

supplemental alpha tocopherol (most common form of Vit. E)

- Can antagonize vitamin K role in blood clotting leading to bleeding.

Vitamin K Bacterial synthesis in

intestines supplies about 10% of our needs

Functions:

- Blood clotting

- Also helps in calcium binding to bones, muscles, and kidneys

Vitamin K: Food sources and RDA

- Liver, soybeans and canola oils

- Broccoli, peas and green beans

- DV is 80 micrograms

Water-soluble vitamins and choline

- Readily excreted from the body

- Very little stored

- Includes the B vitamins and C

- Choline is a related nutrient but is not classified as a vitamin.

Thiamin - B1Functions to release

energy from carbohydrates

Deficiency may lead to enlarged heart and sometimes severe edema

Thiamin - B1: Food sources and needs

- Meats, milk, fish, and cereals.

- Daily Value:1.5 milligrams.

- Toxicity unlikely as it is readily excreted

- No upper limit

Riboflavin - B2Functions- Antioxidant- Releases energy from

carbohydrates

Food sources and RDA– Milk, milk products,

enriched grains, meat, various greens and eggs

– DV is 1.7 milligrams.– No upper limit

Niacin - B3- Functions in fat metabolismDeficiency: - Pellagra (means rough or

painful skin)- Dermatitis and diarrhea- Death can occurFood sources and needs- Poultry, beef, tuna/fish,

asparagus, peanuts- Also coffee and tea- DV is 20 mg and UL is 35 mg

Biotin

Functions– Acts in fat and carbohydrate metabolism– Promotes synthesis of glucose, fatty acids, and

DNA– Breaks down certain amino acids

Deficiency– Scaly inflammation of the skin– Changes in tongue and lips– Decreased appetite, nausea, vomiting– Anemia, depression, muscle pain and weakness– Poor growth

Biotin

Food sources and needs– Cauliflower, Egg yolks, Peanuts, Cheese– Intestinal bacteria synthesize some biotin

making deficiency unlikely– Avidin in raw egg whites binds biotin and

inhibits its absorption– DV is 300 micrograms– No UL

Pyridoxine or Vitamin B6 Functions- Carbohydrate, protein, and fat

metabolism- Synthesis of hemoglobin- Maintain healthy brain function. Deficiency symptoms - Depression, vomiting, skin disorders,

nerve irritation, decreased immune response. Deficiency occur in alcoholism

Food sources and needs- Meat, fish, and poultry- Cereals, potatoes, and milk- Bananas, broccoli, and spinach- Need: 2 mg, UL: 100mg/day

Folate Functions- DNA synthesis- Amino acid metabolismDeficiency- Affects red blood cell division

because DNA cannot form,

- Maternal deficiency in first 28 days of pregnancy linked to neural tube defects

- All women of childbearing years should take 400mcg of synthetic folate per day

Folate Food sources and needs

– Green leafy vegetables, organ meats

– Vegetables, dried beans and orange juice

– Cereals, milk and bread– Destroyed by heat and

processing– DV: 400 micrograms – Pregnant women need

600 mcg– Upper Limit: 1 milligram

Vitamin B12Characteristics- Synthesized by bacteria, fungus,

and other lower organismsFunctions- Folate metabolism- Maintains brain and spinal cord- Forms red blood cellsFood sources and needs- Animal foods - meat, poultry,

seafood, eggs, milk, and milk products

- RDA: 2.4 micrograms per day- Toxicity unknown, no UL

Vitamin C Characteristics- Found in all living tissues- Most animals can synthesize from

glucose- Vitamin C deficiency leads to

scurvy: weakness, poor wound healing, bone pain, fractures, bleeding gums, diarrhea, and bleeding.

Absorption and metabolism- Absorbed in small intestines, 70-

90% is absorbed- Percent absorbed decreases with

increased dosage- High intakes can cause diarrhea

Vitamin C Functions- Collagen synthesis

– Highly concentrated in connective tissue, bones, teeth, tendons, and blood vessels

– Wound healing- Antioxidant (water-soluble)

– Reduce formation of cancer-causing molecules

- Enhanced iron absorption- Immune system

– Vitamin C in large quantities is not shown to prevent colds

– May reduce symptoms

Vitamin CFood sources and needs

– Almost exclusively in fruits and vegetables

– Lost in processing and cooking– DV 60 milligrams – Smokers need an extra 35

milligrams per day – Risk of deficiency

• Alcoholism• Elderly men

– Upper Level: 2 grams per day• Inflammation of the stomach• Diarrhea

Choline- Now called an essential nutrient but not a vitamin- Functions

– Precursor to acetylcholine, a neurotransmitter associated with attention, learning, and memory; muscle control; and other functions

- Deficiency is linked to liver damage- Food sources and needs

– Widely distributed in foods– Milk, liver, and peanuts– Adequate Intake: 425 to 550 milligrams per day– Upper Level: 3.5 grams per day

• Fishy body odor• Low blood pressure