Chapter 6
Vitamins
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 State four general characteristics of vitamins, and explain how water-soluble and fat-soluble vitamins are different.
 Identify which vitamin is deficient in the American diet and two vitamins that are toxic when taken in excess.
 Identify functions and food sources of each vitamin presented.
 List benefits of eating fruits and vegetables.
 Discuss the use of fruits and vegetables on the menu, and describe ways to conserve vitamins when handling and cooking fruits and vegetables.
 Define phytochemicals and give examples of foods in which they are found.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Vitamins = organic substances that carry out processes in the body that are vital to health
◦
Very small amounts are needed—and only small amounts are in foods.
◦
Most vitamins are obtained by eating foods— some are made by intestinal bacteria and one is made in the skin in sunlight.
◦
There is no perfect food with all the vitamins you need in just the right amounts.
◦
Vitamins do contain kcalories.
◦
Some vitamins in foods are precursors .
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 Fat-soluble
◦
Occur in foods containing fats
◦
Stored in the body
◦
Include vitamins A, D, E, and K
◦
Excessive intake of A or
D may lead to undesirable symptoms such as weak bones
 Water-soluble
◦
Includes vitamin C and
B-complex vitamins
◦
B vitamins work in every cell where they function as part of coenzymes
◦
A coenzyme combines with an enzyme to allow the enzyme to do its job
◦
Must take daily because excess is excreted
(except B
6 and B
12
)
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◦
Vitamin C
◦
Thiamin
◦
Riboflavin
◦
Niacin
◦
Vitamin B
6
◦
Folate
◦
Vitamin B
12
◦
Pantothenic acid
◦
Biotin
© 2013 John Wiley & Sons, Inc. All rights reserved.

 What is the vitamin most likely to be deficient in United States? Vitamin D
 In addition, some elderly are deficient in vitamin
B
12 and women capable of becoming pregnant are often deficient in folate.
 What vitamins are most likely to be toxic in excess? Vitamin D, also vitamins C and B
6
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functions:
◦
Fat-soluble vitamin; maintains the health of the eye and vision
(prevents night blindness)
◦
Promote healthy skin and surface linings of
Food Sources:
◦
Milk and eggs
◦
Many red, orange, or yellow fruits and vegetables contain carotenoids
—pigments
—some of which can be converted to vitamin A
◦ the lungs, GI tract, etc.
Supports reproduction, growth, and
(such as beta carotene, which is also an antioxidant) development
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Many red, orange, or yellow fruits and vegetables contain carotenoids and are therefore sources of vitamin A. Some green vegetables, such as spinach and romaine, also contain vitamin A.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functions:
◦
Maintains normal blood levels of calcium and phosphorus by enhancing their absorption into the body.
◦
Normal blood levels of calcium and phosphorus are needed to make and maintain strong bones.
When ultraviolet rays shine on your skin, you make a precursor of vitamin D.
© 2013 John Wiley & Sons, Inc. All rights reserved.





Very few foods contain vitamin D except for fatty fish.
All milk is fortified with vitamin D.
Most cereals are fortified.
Several months of D can be stored in the body, so it is helpful during winter months when sun is not as strong.
All milk in the United States is fortified with vitamin D. Vitamin D is also often added to breakfast cereals, butter, and margarine. Some orange juice is also vitamin D-fortified.
© 2013 John Wiley & Sons, Inc. All rights reserved.




A majority of adults and many children in the
United States do not meet the RDA.
As you get older, the amount of vitamin D your body makes from sun exposure decreases by more than 50 percent.
Vitamin D deficiency in children can cause rickets ; in adults can cause osteomalacia .


Vitamin D deficiency can contribute to osteoporosis
(fragile bones likely to break)—typically seen in older women.
Vitamin D is toxic when taken in excess of the
RDA.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functions:
◦
Antioxidants
◦
Protects against free radicals, which can damage cells
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 Functions:
◦
Important to form
 Vitamin C content of food is reduced by prolonged collagen—a protein substance that provides storage and cooking— because it is water-soluble strength to bones, teeth, and can be destroyed by skin, etc. and helps heal wounds. Collagen is like cement, holding cells
 heat.
Certain people need more vitamin C: smokers, and tissues together.
pregnant and breastfeeding
◦
Makes some hormones.
◦
Strengthens resistance to women, children, and anyone with fever or infection.
infection.
◦
Antioxidant.
© 2013 John Wiley & Sons, Inc. All rights reserved.

© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functions:
◦
All are part of coenzymes needed to get energy from carbohydrate, fats, and protein.
◦
Needed for normal growth.
Food Sources:
Thiamin: pork, beans, watermelon, acorn squash
Riboflavin: milk and milk products, eggs
Niacin: meat, poultry fish, peanut butter, milk, and eggs
© 2013 John Wiley & Sons, Inc. All rights reserved.

(cont’d)
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6
 Functions:
◦
Part of a coenzyme involved in carbohydrate, fat, and protein metabolism
—especially crucial to protein metabolism.
◦
Makes hemoglobin in red blood cells—carries oxygen to cells.
◦
Helps immune system.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functions:
◦
Folate is part of coenzymes required to make DNA so it is needed to make all new cells.
 Pregnant women are at risk of folate deficiency, which may cause neural tube defects (malformed brain or spine) during first few months of pregnancy.
 All women capable of becoming pregnant should take 400 mcg of synthetic folic acid daily from fortified foods (breads) or supplements in addition to natural folate in foods.
© 2013 John Wiley & Sons, Inc. All rights reserved.

© 2013 John Wiley & Sons, Inc. All rights reserved.

12
 Functions:
◦
Part of a coenzyme needed to make new cells and DNA.
◦
Activates the folate coenzyme.
◦
Ensures normal functioning of the nervous system.
 Found only in animal foods so could be problem for vegans.
 Vitamin B
12 is harder to absorb for elderly, who may need foods fortified with B
12 or supplements that use crystalline vitamin B
12 absorb).
(easier to
 B
12 deficiency affects nervous system.
© 2013 John Wiley & Sons, Inc. All rights reserved.

12
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Three reasons to eat more fruits and vegetables:
◦
Most fruits and vegetables are major contributors of a number of nutrients that are underconsumed—vitamins A and C, folate, dietary fiber, etc.
◦
Consuming them is associated with less risk of many chronic diseases such as heart disease.
◦
Most fruits and vegetables, when prepared without added fats or sugars, are relatively low in kcalories.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 To get a healthy variety of fruits and vegetables, think color.
 Store fruits and vegetables properly and use at optimum time for freshness, color, flavor, and nutrition.
 Keep most fruits and veggies cold and moist.
 Consider cooking methods such as blanching, stewing, steaming, grilling, sautéing, baking, boiling, and braising.
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 When cooking, consider texture and flavor change. Keep cover off the pot of vegetables such as cabbage, cauliflower, Brussels sprouts.
 Do not overcook!
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 Buy fresh, high-quality produce, and check closely when receiving.
 Store properly (close up the wrapping tightly to decrease exposure to the air, which pulls out water) and use product when it is still fresh.
 When cooking: Avoid peeling, prepare small amounts at a time, cook quickly using appropriate methods such as steaming, cook just until tender.
© 2013 John Wiley & Sons, Inc. All rights reserved.

© 2013 John Wiley & Sons, Inc. All rights reserved.

(cont’d)
 Fruits are a natural in salads, such as pineapple and raisins with carrots.
 Roasted fruits with shallots are a wonderful base on which to place proteins. Place chicken on a bed of roasted peaches and mango with jicama or sautéed bok choy.
 Fruits are a natural for dessert—fresh, roasted, or baked into a cobbler with a oatmeal almond crust.
 Berries are great when you want vibrant colors in sauces, purées, toppings, and garnishes.
© 2013 John Wiley & Sons, Inc. All rights reserved.

(cont’d)
 Vegetables allow you to serve what looks like a big portion with reduced kcalories and no fat or cholesterol.
 When using vegetables, be mindful of the season for maximum flavor, visual appeal, and value. Also think variety.
 Olives add exquisite flavor—there are many great varieties, such as Manzanilla or Gaeta.
© 2013 John Wiley & Sons, Inc. All rights reserved.

© 2013 John Wiley & Sons, Inc. All rights reserved.

© 2013 John Wiley & Sons, Inc. All rights reserved.

 Functional foods are foods that contain an ingredient that provides health benefits beyond the nutrients in the food.
For example, bottled drinks are enhanced with herbs and taurine.
 Many of the healthpromoting ingredients in functional foods are phytochemicals
— bioactive compounds found in plants that are linked to decreased risk of chronic diseases. For example, cocoa is a rich source of antioxidants that may help protect your blood vessels and heart.
© 2013 John Wiley & Sons, Inc. All rights reserved.

 Like dietary supplements, functional foods will not compensate for a poor diet. Whole foods still contain the right amount and balance of nutrients and phytochemicals to promote health.
© 2013 John Wiley & Sons, Inc. All rights reserved.