Unit 21 Flashcards
Phytochemicals and genetically modified foods (45 cards)
What are phytochemicals?
Biologically active compounds of plants (protect them from bacteria, animals, and give pigmentation and flavor) believed to reduce risk of chronic disease in humans
Are phytochemicals essential?
No, none of them are, but they are beneficial
How are phytochemicals useful to our tissues?
Have protective and antioxidant properties
Are some phytochemicals toxic to us?
yes
What disease can phytochemicals protect us from?
- cancer
- heart disease
- high blood pressure
- other chronic diesease
The correct balance of phytochemical is unknown, but to get get adequate levels, we need to:
- follow the advice in Canada’s Food guide
- eat a variety: don’t eat the same foods everyday
T/F: phytochemicals can reduce free radicals
True
How do phytochemicals work?
- antioxidant
- hormonal action
- stimulation of enzymes
- protect DNA
- physical action
How do phytochemicals work as an antioxidant?
protect cells against oxidative damage and reduce risk of developing certain types cancer
Phytochemicals as antioxidants
What foods do we find allyl sulfides in?
garlic
Phytochemicals as antioxidants
What foods do we find cartenoids in?
carrots
Phytochemicals as antioxidants
What food do we find flavonoids in?
Berries
Phytochemicals as antioxidants
What foods to we find polyphenols in?
Grapes
What are the hormonal actions of phytochemicals?
isoflavones found in soy imitate human estrogens and help to reduce menopausal symtpoms and osteoporisis
How do phytochemicals stimulate enzymes?
Indoles found in broccoli and cabbage, stimulate enzymes that make estrogen less effective
What type of cancer could broccoli protect against?
breats cancer – make estrogen less effective
How do phytochemicals proctect DNA?
capsacin found in hot peppers, protects DNA from carcinogen
What is the theory behind how cranberries reduce the risk of urinary tract infections?
Some phytochemicals bind physically to cell walls preventing adhesion of pathogens to human cell wall. Proanthocyanidins are responsible for the anti-adhesion properties of cranberries
How many phytochemicals have been identified? What does this mean in terms of supplements?
Up to 10000 have been identified, they cannot all be isolated and put into a supplement
How health benefits of phytochemicals associtaed with foods or supplments?
Foods
What is an example of a phytochemical supplement that can harm health?
beta-carotene, leads to more lung cancer
What is solanine?
The green part of potatoes that occurs when they are exposed to light. This is a natural defense againts insects eating them (bitter)
Symptoms include diarrhea, vomitting, headache, paralysis
What is aflatoxins?
Fungi growing on nuts/peanuts, dried foods, grains, and spices which can cause liver cancer with chronic exposure
What are 2 anti-nutrients?
- oxalic acid
- phytates