Chapter 10

The Water Soluble Vitamins (WSV) – B vitamins and Vitamin C

True/false

1. Taking vitamin supplements is never harmful because your body eliminates any excesses that you don’t need

2. Taking vitamin C supplements can help you ward off the common cold

Vitamins

False1. Some vitamins are stored in the body

and can build up to toxic levels if taken in excess

2. There is no clear evidence that vitamin c supplements protect you from the common cold

OverviewVitamins differ from CHO, fat, and protein in 3

ways:• Structure

– Single units– Not linked together

• Function– Do not yield energy– They assist enzymes that release energy from CHO,

fat, and protein• Measurement

– Micrograms (ug or mcg)– Milligrams (mg)

Overview• Bioavailability

– Amount absorbed and used by the body• Precursors

– Inactive forms of some vitamins, also known as provitamins• Organic –

– Being organic, they can be destroyed• Solubility

– Water soluble vitamins are hydrophilic– Fat soluble vitamins are hydrophobic

• Toxicity– Too much of some vitamin can be harmful to the body

What are Vitamins• Needed for growth, reproduction and

overall good health• They are essential nutrients• Deficiency of one will cause physiological

symptoms• There are 13 vitamins, can be water

soluble or fat soluble• Vitamins D, K, niacin and biotin can also

be synthesized (made) by the body

Vitamins

• Water soluble vitamins can be destroyed by air, water, or heat

• Vegetables and fruit begin to lose their vitamins almost immediately after being harvested

• Fat soluble vitamins tend to be more stable

• Some preparation treatment can cause the loss of vitamins

Fat-Soluble and Water-Soluble

Preserving your vitamins

• Don’t expose your produce to air, keep in air tight container

• Cook with minimal liquid to prevent loss of vitamin through leeching

• Washing rice before cooking will wash away all the b vitamins that were sprayed on during enrichment process

Preserving your vitamins

• Prolong heating will destroy water soluble vitamins, especially vitamin C

• Vegetables cook in microwave or stir fry can have 1 ½ times more vitamin C after cooking than if they were boiled

• Keep your fruits and vegetables cool

Characteristics of WSV

• B vitamins share a common role as coenzymes to help several enzymes produce reactions in the body cells

• Deficiencies of WSV are rare in USA• Deficiencies in the B complex and vitamin C

is associated with alcoholism and the elderly, related to diets that are not balanced

• B vitamins are needed to use all macronutrients efficiently

Thiamin (B1)• The first to be discovered• Chief Functions

– Part of coenzyme Thiamin pyrophoshotate (TPP) needed for energy metabolism

– Helps to break down alcohol in the body• Food sources

– Enriched and whole grains such as bread and ready to eat cereal, pasta, and rice.

– Pork, is the biggest source of naturally occurring thiamin

• Easily destroyed by heat

Thiamin (B1)• Toxicity

– Nontoxic, so no upper limit has been set• RDA :

– 1.1milligram (mg) women daily– 1.2mg men daily

• Deficiency Diseases– Beriberi – Wernicke-Korsakoff found in alcoholics

Thiamin (B1)

• Deficiency symptoms– Enlarged heart– Cardiac failure– Muscular weakness– Poor short-term memory– Confusion– Anorexia– Weight loss

Riboflavin (B2)• Light sensitive B vitamin, easily destroyed by

ultraviolet light and irradiation• Abundant in milk• Functions

– Part of coenzymes that helps to turn carbohydrate, proteins, and fats, into energy and to keep cells healthy

– Enhances the functions of niacin and B12• Sources

– Milk, yogurt, enriched grains• RDA:

– women - 1.1milligram (mg)/day– Men – 1.3 mg

Riboflavin (B2)

• Deficiency Disease– Ariboflavinosis

• Deficiency Symptoms– Sore throat– Swollen mouth– Inflamed tongue– Dry and scaly lips– Skin lesions

• Toxicity - None

Niacin (B3)Other names:

nicotinic acid, nicotinamide and niacinamideTryptophan is a precursor of niacin• Functions

– Needed to use the energy in food– Keep skin and digestive system healthy and functioning– Helps to lower LDL, raise HDL cholesterol– Nicotinic acid as a drug is 40 times the RDA prescribed

by doctors to lower LDL• Deficiency Disease

– Pellagra (Four Ds) common among alcoholics and people with poor diet

Niacin (B3)

• Deficiency Symptoms– Dermatitis- inflammation or irritation of the

skin– Dementia – loss of memory– Diarrhea– Death

Niacin (B3)• Sources

– meat, fish, poultry, enriched whole grain breads and fortified cereals,

• Toxicity– No known danger from consuming too much

niacin from foods– Over consuming niacin supplements may lead

to:• painful flush, liver damage, high blood glucose,

nausea, vomiting– Never consume high amounts of niacin unless

prescribed by a doctor

Niacin (B3)

• RDA : – Women - 14 milligram/day– Men – 16mg/day

• Upper level – 35mg/day

Vitamin B6• Other names:

– Pyridoxine, pyridoxal, prydoxamine• Functions

– An active co-enzyme with over 100 enzymes involved in the metabolism of proteins

– Needed to convert tryptophan into niacin and serotonin

– Needed to make red blood cells– Recently found that B6 along with folate and

B12 help reduce risk of heart disease

Vitamin B6 • Deficiency symptoms

– Sore tongue– Scaly red skin– Depression– Confusion– Possibly anemia– convulsions

(B6)• Sources

– Ready-to-eat cereal, meat, fish, poultry, shellfish, legumes, fruits, green and leafy vegetables

– Easily destroyed by heat

• Toxicity– Supplement abuse (500-6000mg/day) for two months may result in

• Difficulty walking• Tingling sensations in legs and feet

• RDA: – Women - 1.3 to 1.5 milligram/day– Men – 1.3 to 1.7 mg/day

• Upper level– 100 mg/day

Folate• There are two forms:

– Folate – naturally occurring in food– Folic acid or folacin – synthetic form, added to food or

found in supplements• Functions

– Vital for synthesis of DNA– Helps to maintain healthy red blood cell – Helps red blood cells divide and increase in adequate

numbers– Prevents birth defect (neural tube defects)– Helps to fight cancer – colon Cancer– Helps the body use amino acids

FolateDeficiency• Stops cell division (beneficial in cancer pt, by

stopping growth of tumor cell)• Neural tube defects

– Spina bifida• Spinal cord and backbone aren’t properly developed• Learning and physical disabilities• Inability to walk

– Anencephaly• lack of complete brain , • Baby can’t move, think, or function• death shortly after birth

Folate

Deficiency• Megaloblastic anemia

– Abnormally large red blood cells– Decreased oxygen carrying capacity

• Macrocytic anemia - result of megaloblasts– Feel tired, weak and irritable– Shortness of breath

• Because folate needs vit B12 to produce healthy red blood cells, a deficiency of either vitamin can lead to macrocytic anemia

Folate deficiency results in

macrocytic anemia.

Recommendation for women

• Take folate 1 month before conception and through the 1st trimester to prevent neural tube defects.

• Synthetic folic acid has a stronger protective effect than the food folate

• Since 1998, the FDA has mandated that folic acid be added to all enriched grains and cereal products

Folate• Sources

– Enriched pasta, breads, rice and cereals, leafy green vegetables, legumes, seeds, asparagus, broccoli

• Toxicity – from synthetic– Masks vit B12 deficiency symptoms– Sleep disturbances, irritability, GI problems

• RDA: The body absorbs synthetic folic acid more easily than folate from foods. (1.7 times more efficiently)– 400 microgram for most adults– Pregnant women - 600 microgram/day– Upper limit – 1000 microgram/day from enriched and

fortified foods

Vit B12 (cobalamine)

• Needs intrinsic factor to be absorbed• Functions

– Needed to use certain fatty acids and amino acids

– Needed to make DNA– Needed for healthy nerves– Activates folate and folate can activate b12 to

coenzyme– Part of the heart healthy B vitamins

Vit. B12

• Deficiency– Pernicious (harmful) anemia

• Occurs in individual who are not able to absorb B12 because of lack of intrinsic factor

• Gets regular shot of B12 directly into the blood stream

• Can take years to develop because the liver stores plenty of B12

– Can also cause macrocytic anemia because B12 works closely with folate

Vit B12 (Cobalamine)• Food Sources

– meats, fish, poultry, milk and milk products, fortified foods

• Toxicity -None• RDA: 2.4 microgram/day for most adults

Vitamin C• Ascorbic acid• Functions

– Act as coenzyme needed to make and use certain amino acids

– Needed to make collagen – • the most abundant protein in the body • Collagen connects and supports all your body part like glue• Needed for healthy bones, teeth, skin, and blood vessels

– Act as antioxidant– Helps in iron absorption in plant foods– Boost the immune function system by

• Helping the body to produce white blood cells to fight infections

Vitamin C• Deficiency – affects the entire body

– Scurvy• Bleeding gums• Rough rash on the skin• Wounds that won’t heal• Anemia

• Sources– citrus fruits, Red and green sweet peppers,

strawberries, pineapple, kiwi fruit, cantaloupe, mangoes,, tomatoes, potatoes, green vegetables, fortified fruit juices.

Vitamin C• Toxicity from supplements

– >1000mg or 1g may cause iron overload (hemochromatosis)

– >3,000 mg has been shown to cause diarrhea, nausea and stomach cramps

• RDA: – Women - 75 milligram/day– Men – 90 milligrams/day– Smokers + 35 mg/day

• Upper level– 2,000 milligrams

Supplement Smarts

How Should You Get Your Vitamins?

• FDA approval not required for ingredients in use prior to 1994; FDA cannot remove supplement from marketplace until shown to be harmful

• Consult health professional before taking vitamin/mineral supplements– Read supplement label carefully

• USP seal of approval tests supplement to ensure quality and safety (but does not endorse or validate health claims)