Judith E. Brown Prof. Albia Dugger Miami-Dade College Phytochemicals and Genetically Modified Food Unit 21

Phytochemicals People who eat lots of fruits, vegetables, whole grains and other plant foods are less likely to develop many health problems Plants contain thousands of potentially beneficial substances called phytochemicals

Key Terms Phytochemicals Chemical substances in plants which likely perform important functions in the body Zoochemicals Chemical substances in animal foods which likely perform important functions in the body

Nutrition Superstars

Some Phytochemicals

Characteristics of Phytochemicals Functions in plants: Provide color and flavor Protect from insects, microbes, oxidation Used in energy processes, hormones Not all phytochemicals are healthful Naturally occurring toxins

Phytochemicals and Health Diets rich in phytochemicals protect against many diseases Heart disease, certain cancers, infectious diseases, osteoporosis, type 2 diabetes, stroke, hypertension, cataracts, age-related macular degeneration, and other disorders

Age-Related Macular Degeneration Age-related macular degeneration Eye damage caused by oxidation of the macula (central portion of eye responsible for detail) Leading cause of blindness in adults over 65 Prevented by carotenoids (antioxidants)

Cataracts Complete or partial clouding of the lens of the eye

Phytochemicals Work in Groups Most (if not all) phytochemicals work together when consumed at the same time Pills containing individual phytochemicals don’t have the same effect

Beta-Carotene Studies Smokers with high beta carotene levels from fruits and vegetables had low cancer rates Smokers who took beta carotene supplements had higher cancer rates Conclusion: A combination of chemicals in plant foods reduced cancer

Plants Beat Pills

Vegetable Extracts and Essences It would take 100 pills to get the same amount of just one phytochemical (sulforaphane) in one serving of cruciferous vegetables such as broccoli

Key Terms Cruciferous vegetables Sulfur-containing vegetables whose outer leaves form a cross (crucifix) Includes broccoli, cabbage, cauliflower, brussels sprouts, mustard, collard greens, kale, bok choy, kohlrabi, turnips, broccoflower, and watercress

How Do Phytochemicals Work? Phytochemicals can: Act as hormone-inhibiting substances to prevent initiation of cancer Act as antioxidants that prevent and repair damage due to oxidation Neutralize enzymes that promote cancer Modify utilization of cholesterol Decrease formation of blood clots

Phytochemicals

Top Antioxidants Bright-colored pigments are strong antioxidants Zeaxanthin Anthocyanin Lycopene

Naturally-Occurring Food Toxins Solanine In green potatoes Oxalic acid In dark green, leafy vegetables Cyanide In cassava

Naturally-Occurring Food Toxins Ackee fruit Part edible, part deadly poison

Caffeine Caffeine is a habit- forming phytochemical Withdrawal can cause headaches

Genetically Modified (GM) Foods Genetic engineering Process of biotechnology used to modify the composition of a food by altering its genetic makeup – includes transfer of genes from one species to another Food products produced are sometimes called GM or GMOs (genetically modified organisms)

Genetic Modification of Plants

Genetic Modification of Animals Biotechnology has also genetically engineered animals used for food Atlantic salmon, pigs, cattle, chickens Animal products from cloned animals make up a small fraction of meat sales

Are GM Foods Safe? Over 60% of processed foods contain GM ingredients 80% of soybeans, 30% of corn are GM Tomatoes, squash, cantaloupe, potatoes Organic produce is not GM

GM-Free Foods

Benefits and Concerns of GM Foods