Phytonutrients

Question 1

What are phytochemicals?

Answer 1

Chemicals made by plants in reaction to their environment

Question 2

State 4 common effects of phytonutrients on the body?

Answer 2

Function as antioxidants

Reduce DNA damage

Mimic or interact with hormones

Regulate the cell cycle

Question 3

Name 3 types of phenols and polyphenols?

Answer 3

Flavonoids (quercetin, kaempferol)

Phenolic acid

Lignans

Question 4

What are flavonoids and what actions do they have?

Answer 4

They belong to the polyphenols family and are responsible for colouring fruit and vegetables

Anti-cancer
Antioxidant
Anti-inflammatory

Question 5

Catechins are a type of flavonoid, what actions do they have on the body? (3)

Answer 5

Anti-inflammatory

Protect cartilage by inhibiting collagen breakdown

Lessen joint degeneration (green tea)

Question 6

State 4 uses/effects of the flavonoid quercetin?

Answer 6

CVD prevention

Cancer - applied topically reduces skin damage from radiotherapy, chemo: increases therapeutic effects of cisplatin and protects kidney from damage by it

Athletes - improves lean body mass when taken as a supplement

Immune function - inhibits histamine release by mast cells, reduces asthma

Question 7

List 3 sources of kaempferol?

Answer 7

Apples

Onions

Grapes/red wine

Question 8

State 3 functions of kaempferol?

Answer 8

Strong antioxidant

Prevents arteriosclerosis

Chemopreventive - inhibits formation of cancer cells

Question 9

Naringin is found where?

Answer 9

Grapefruit

Tomato paste

Question 10

State 4 effects of naringin?

Answer 10

Antioxidant

Anti-carcinogenic

Cholesterol lowering

Reduces retinal disease linked to diabetes

Question 11

Isoflavones are also called what? And what do they have?

Answer 11

Phytoestrogens

They have estrogen activity

Question 12

Soy isoflavones have amphoteric actions, what does this mean?

Answer 12

Two actions

Mimics effects of oestrogen in some tissues

Blocks the effects of oestrogen in others

Question 13

Soy isoflavones have been found to what?

Answer 13

Inhibit enzymes that play critical roles in stimulating cell proliferation - anti-tumour property

Question 14

State 4 conditions isoflavones help with?

Answer 14

Cardiovascular disease - sub soy protein for animal lowers cholesterol, 80mg/d soy isoflavone extract for 5 weeks decreased arterial stiffness

Cancer - breast cancer rates in Asia lower than western countries, high soy intake during adolescence associated with lower risk of breast cancer, slows prostate tumour growth

Osteoporosis - soy protein can increase BMD

Menopause symptoms - decreases severity of symptoms

Question 15

How many g of soy protein per day to prevent osteoporosis?

Answer 15

40

Question 16

How many g of soy protein a day to reduce severity of menopausal symptoms?

Answer 16

20-60

Question 17

Discuss isoflavones and thyroid function?

Answer 17

Soy isoflavones have been found to inhibit he activity of thyroid peroxidase - enzyme required for thyroid hormone synthesis

BUT high intakes of soy isoflavones do not appear to increase the risk of hypothyroidism as long as dietary consumption of iodine is adequate

Question 18

State 3 sources of lignans?

Answer 18

Beans/pulses

Flaxseeds

Sesame seeds

Question 19

Diets rich in plant lignans are consistently associated with reductions in what?

Answer 19

Cardiovascular disease

Question 20

Flaxseeds are high in lignans, taking 40g orally per day improves what?

Answer 20

Mild menopausal symptoms

Question 21

Where are proanthocyanidins found?

Answer 21

Grapes, cocoa and apples

Question 22

Where is resveratrol found?

Answer 22

Grapes, blueberries and peanuts

Question 23

State 3 benefits of resveratrol?

Answer 23

Antioxidant

Heart health

Anti cancer - found to inhibit the proliferation of a variety of human cancer cells

Question 24

What are phytosterols?

Answer 24

Plant derived lipids that are similar in structure and function of cholesterol

Question 25

Discuss phytosterols and cholesterol levels?

Answer 25

High intake of plant sterols lowers total and LDL cholesterol