Phytonutrients Flashcards
What are phytonutrients?
- Chemical compounds produced by plants
- = beneficial to human health and help prevent various diseases.
- Found in fruit, veg, tea, nuts, grains, beans, herbs and spices and give foods taste, fragrance, colour.
The TWO by-products that produce phytonutrients in plants?
- Glycolysis (metabolic process to break down sugars to release ATP)
- Photosynthesis (production of gluclose and O2 from water and C02 catalysed by sunlight.
Why eat the whole food, not single element?
- Antioxidants can recycle each other.
- Health benefits of eating fibre and other macros all in one.
- Beta-carotene supplemention (isolated) worsened lung cancer patients who smoked.
Difference between primary and secondary metabolites formed via glycolysis or photosynthesis.
Primary metabolites:
Compounds necessary for plant survival ie macros (p, l, c), enzymes and chlorophyll.
Secondary metabolites:
Synthesised by plant in reaction to its environment ie an adaptive response
1. Evolve to facilitate the survival of the plant.
2. Deter predators and protect from infection.
What are metabolites?
Products of metabolism or substances essential to metabolism
x3 roles of secondary metabolites in plants
- Protection against
- herbivores
- plant pathogens
- against other plants. - Protection against physical stressors eg ultraviolet light (suncreen!)
- Signals for communication and to attract pollinators (to reproduce for single sex plants)
*What is the role of secondary plant metabolites in the human body?
- Antioxidants eg quercetin
- Regulate cell cycle
- Increase detoxification of carcinogens and toxins eg chlorophyl.
- Reduce DNA damage (e.g. lycopene in tomatoes).
- Mimic or interact with hormones and other body chemistry (e.g. lignans in flaxseeds can support oestrogen levels when low; fermented soy).
Why do organic plants have higher phytonutrient levels?
Have to protect themselves in their environment as they don’t get ‘support’ from pesticides, fertilisers and perfect conditions.
What factors can determine the levels of phytonutrients in plants?
- Its chemotype (secondary metabolites)
- Soil and water conditions.
- Fungi and mycorrhizae.
- Insects friends and foes.
- Climate.
- Seasonal cycles.
- Variability of plant part.
- Bacteria, virus and pathogens.
- Humans and other animals around them (deforestation).
- chemotypes: different species have different compositions of the secondary metabolites.
Mycorrhizae?
Symbiotic association between a fungus and a plant - important for plant nutrition ans soil biology.
Which class of phytonutrients include morphine, vinblastine and digoxin and can be very poisonous?
Alkaloids
Morphine - opium
Vinblastine = chemo drug (African violets)
Digoxin = heart failure drug (found in foxglove)
Name three regular alkaloids
- Solanine and chaconine - alkaloids from nightshade frmily (anticholinesterase blocks activity of enzyme that breakds down aceytlcholine). Avoid in arthritis patients.
- Caffeine - toxic in high doses. Strong effect on cognition, BP, sleep and endurance. Caffeine blocks adenosine (hormone that promotes sleep).
- Phytates - prevent mineral absorption
What benefits do blue, black, purple fruits confer?
FLAVANOIDS: in highest concentration here
Antioxidants:
1. Fights ROC
2. Support heart health [think red colour for blood!]
3. Circulation
4. Vision
Blueberries, blackberries, red cabbage, aubergines, black olives.
*FIVE main phytonutrients classifications?
- Phenols and polyphenols (biggest group)
- Phytosterols
- Terpenes
- Organosulphur compounds
- Alkaloids
PTPOA or POPAT
What benefits do green plants confer?
High in chlorophyll and nutrients:
1. Supports liver detoxification
2. Binds with toxins in the gut preventing absorption into the body.
Kale, spinach, collard, broccoli, brussels sprouts, parsley, lettuce, avocado, watercress, cucumber.
What therapeutic benefits does each colour of plant confer?
Green for detox
Red for inflammation
Orange/yellow for immune, vision and joint health
White/brown (sulphur) for circulation and liver detox
What benefits do RED PLANTS CONFER?
LYCOPENE: Reduces inflammation
- High in vitamin C
- Supports the prostate.
Tomatoes, guava, watermelon.
What benefits do orange, yellow plants confer?
- Immune system
- Vision
- Joint health.
Carrot, squash, sweet potatoes, orange, papaya, corn, melon, peppers, pumpkin, turmeric.
What benefits do white, brown plants confer?
ORGANOSULPHUR
1. Supports heart
2. Circulation
3. Liver detox (just like green)
Garlic, onions, leeks, ginger, white cabbage, mushrooms, parsnips.
What do flavanoids determine?
Colour of a plant ie pigment. Anything with a colour contains a flavanoid. The darker the more flavanoids they have. Essentially in every plant.
Phytonutrients classified according to chemical compounds. Five main classes are?
- Phenols and polyphenols
- Terpenes
- Phytosterols
- Organosulphur compounds
- Alkaloids
Name the x4 polyphenols category
- Flavonoids (quercetin and rutin, naringenin, catechins, isoflavones).
- Phenolic acids eg gallic acid in grapes or saliciylic acid eg white willow bark (asprin)
- Lignans eg flaxseeds
- Stilbenes eg resveratrol
Flavonoids belong to the polyphenol family and has six subgroups. List three and one example each.
- Flavonols (e.g. kaempferol - in kale, spinach; quercetin in red onions)
- Flavones (e.g. apigenin - in parsley, celery, chamomile).
- Isoflavones (e.g. genistein and daidzein - in soybeans).
- Flavanones (e.g. naringin - in grapefruit).
- Anthocyanins (e.g. cyanidin - in red grapes, blackberry, blueberry).
- Flavanols or catechins (e.g. epicatechin - in green tea, cocoa).
What kind of phytonutrient is quercetin?
Flavanol
Flavanoid
Polyphenol
What classification does terpenes contain?
Carotenoids:
ABLL
1. Beta-carotene
2. Lycopene
3. Astaxanthin
4. Lutein.
Name three phytosterols (lipids)
Tocopherols (vit E)
1. n-3, 6, 9
2. Fatty acids
Lowering cholesterol
Managing blood lipids
Which x2 flavonoids can be found most notably in green tea?
Catechins & epicatechins
Three functions of catechins and epicatechins inc therapeutic uses
## Footnote
(Also to be found in oolong tea, black tea,cocoa, black grapes, berries apples, pears, plums, vinegar.)
Catechins & epicatechins
-
Anti- inflammatory: (antioxidants). Inhibits COX and 5-lipoxygensase
a) Asthma / eczema.
b) Urticaria / hay fever (reduces histamine).
c) Anti-cancer.
d) IBD -
Neurological health: (inhibits monoamine oxidase). Monoamines include serotonin, dopamine, adrenaline and noradrenaline.
a) Parkinson’s (neuroprotective).
b) Depression.
c) Cognitive disorders. -
Cardiovascular health: (think purple for blood eg beetroot and berries) - antioxidants
a) Protects vascular endothelim eg drink purple grape juice or black tea
b) Lowers BP & LDL-cholesterol.
c) Increased NO prod. (vasodilation).
d) Reduces insulin resistance.
Joint health:
a) Lessen joint degeneration in OA & RA
b) Protects cartilage by inhibiting proteoglycan and collagen breakdown.
What phytonutients are in berries?
Flavanoids, catechins and epicatechins
Quercetin role in anti-cancer treatment
Anti-tumour
1. Induces cell cycle arrest eg leukaemic, prostate and ovarian cancer cells)
2. Induces apoptosis.
3. Inhibits blood vessel growth. In prostate and breast cancers, quercetin targets the VEGFR-2-mediated angiogenesis pathway.
4. Anti-metastatic properties.
5. Reduces head / neck skin damage during radiotherapy.
6. Increases efficacy of some types of chemotherapy.
How quercetin can benefit cardiovascular and immune health.
Quercetin is a FLAVANOL.
-
Cardiovascular health:
a) Powerful antioxidant
b) Protects vascular endothelium
c) Inhibits LDL oxidation.
d) Vasodilatory effects (via NO release)
e) Reduces platelet aggregation
f) reduces BP (in hypertensives) via ACE-inhibiting properties (ACE increases BP).
- Supports endurance by increases blood circulation.
* Dosage: 150 mg‚Äí1000 mg per day.
Immune health:
- Anti-inflammatory: inhibits LOX & COX, potent down-regulator of NF-kB.
- Anti-histamine inhibits mast cell degranulation.
- Reduces brain inflammation (protective against Alzheimer’s and Parkinson’s).
What vitamin would you take alongside anti-histamines to reduce histamine?
Vit C
Anti-histamine foods?
Quercetin, bee pollen, Serapetptase, spirulina
How can increasing food sources of quercetin be beneficial for gout sufferers?
Quercetin can inhibit xanthine oxidase (normally converts purines to increase uric acid)
Also shitake, barley grass.
How can the absorption of quercetin into the blood be enhanced?
- Onions and shallots contain quercetin in its unbound (glycone ie attached to a sguar molecule) form, which may make absorption easier.
- Quercetin is hydrophobic, so is best absorbed with fats, emulsifiers or apple pectin.
- Drip feed it in as small and more often 150-1500mg per day.
- Quercetin and nettle a good combo.
CYP3A4 function?
Breaks down medical drugs
Which flavonoid contained in grapefruit inhibits intestinal CYP3A4 and is therefore contraindicated with numerous medications?
Naringin.
CYP3A4reaks down medical drugs
CYP450 are normal P1 enzymes.
Where is naringin found?
Naringin (grapefruit, tomatoe paste and other citrus fruits).
Intestinal bacteria metabolise it down to naringenin.
How can naringin aid diabetes?
- Inhibits ‚’aldose reductase’ (associated with diabetic complications).
- Reduces diabetic retinopathy and neuropathy.
x3 therapeutic uses for Naringin?
- Atherosclerosis (incl. prevention)
- Hyperlipidaemia.
- Cancer prevention (esp prostate)
- Reduces acceleration and complications of diabetes.
NB Similar to quercetin but no histamine properties.
Name best food sources of isoflavonoids
- Mostly soy
- Legumes e.g. lentils
What is the difference between a glycone and an aglycone?
Glycone = attached to a sugar molecule (isoflavonoids + quercetin, it is attached to a sugar molecule too).
Aglycones = compound without a sugar group attached.
Aim is to convert glycones into aglycones.
Discuss how compromised digestive capacity affects the absorption of isoflavones from soybeans?
- Some colonic bacteria can convert the soy isoflavone daidzein to equol - a metabolite with greater oestrogenic activity than daidzein.
- Equol production depends on gut flora and is therefore influenced by diet.
Active fermented soy = easiest to digest eg tempeh, natto.
What increases equol production (better oestrogenic activity than daidzein)?
- Eating isoflavones from a young age
- Seaweeds
- Green tea
What two phytonutrients are in green tea?
Catechins and epicatechins
Isoflavones (equol)
Recommend FOUR phytonutrients that could be useful for a client wanting to lower their LDL-cholesterol
1. Catechins / epicatechins: green tea, oolong tea and black tea, cocoa, black grapes, berries, apples, pears, plums, vinegar.
2. Naringin: Citrus fruits (esp. grapefruit), tomato paste.
3. Isoflavonoids: Soy, lentils, peas, chickpeas, peanuts, alfalfa sprouts, red clover, brussel sprouts.
4. Phytosterols: Unrefined vegetable oils, nuts, seeds, whole grains and legumes.
Discuss the interplay between isoflavones and oestrogen.
Selective oestrogen modukators
Weak oestrogenic activity
Bind to oestrogen receptors, mimicking the effects of oestrogen in some tissues and antagonising (blocking) the effects of oestrogen in others.
- Anti-oestrogenic effects in reproductive tissue could help reduce the risk of hormone-associated cancers (breast, uterine and prostate)
- Oestrogenic effects in other tissues can help maintain bone density (NB good gut flora needed to make K2 for bone calcification).
- Reduces menopausal symptoms
- Supports low oestrogen conditions eg amenorrhoea.
- Consider isoflavones as selective oestrogen modulators*
List FIVE dietary recommendations for a client in order to support their bone mineral density.
- Green tea (catechins)
- Fermented soy products eg. tempeh (isoflavones, lysine), natto (isoflavones, vitamin K2)
- Ground flaxseed and sesame seeds (lignans)
- Dark green leafy vegetables (Magnesium, vitamin K1)
- Oily fish / fish oil (Vits D & A)
## Footnote
Adequate protein
Eliminate junk food
Lower caffeine and red meat
Use himalayan or celtic sea salt not table salt.
Soy protein supplementation issue? Dose for menopausal symptoms?
Ethanol washing bad. Water good.
- Soy protein isolates prepared by ethanol wash process lose most of associated isoflavones.
- Aqueous wash processes better (protein isolates retained).
80-160 mg isoflavones / day.
Drug soy protein interacts with?
Warfarin.
What types of soya are NOT to be recommended and why?
- GM (in a lot of animal feed).
- Soy protein isolate highly processed (if unfermented and may be GMO.)
- Highly-processed soy flour isoflavones stimulate tumour promoting growth genes (minimally processed soy flour stimulate cancer-suppressing genes)
NB Soy product fear stems from industrially-processed products, not its whole form.
NB Soy can be difficult to digest. Fermented is more easily digested.
Daidzein is primary lignan in soy.
What soy alternative = ‘Western equivalent’ of phytoestrogens? Most abundant source?
Lignans.
Flaxseeds = most abundant source (85.5 mg lignans)
## Footnote
Also in:
1. Sesame seeds
2. Beans and pulses
3. Cruciferous vegetables.
How are lignans metabolised?
Intestinal bacteria to form two PHYTOESTROGEN compounds:
1. Enterodiol
2. Enterolactone
NB both isoflavones and lignans metabolised by gut bacteria.
What is the oestrogen-modulating effects of lignans. Include therapeutic uses
- Bind to oestrogen receptors, exerting an oestrogenic effect
a) If oestrogen levels low increases oestrogenic activity.
b) If high, lignans antagonise endogenous oestrogens.
Therapeutic uses:
1. Menstrual irregularities*
Dosage: 2 tbsp freshly ground whole flaxseed per day (i.e. seed cycling).
2. * Menopause support
a) reduces frequency and intensity of hot flushes
b) improves vaginal atrophy,
c) aids icognitive function
d) supports bone density
e) reduces osteoporosis risk.
Dosage: 2 tbsp flax per day.
How do lignans exert their anti-cancer mechanisms?
**Hormonally-driven breast and prostate cancer, endometrial and ovarian cancer.
-
Modulation of oestrogen metabolism and receptor signalling pathways leading to:
a) decreased cell proliferation
b) angiogenesis. - Strong anti-oxidant properties.
- Decreasing 5a-reductase activity, thereby reducing the more biologically potent DHT (prostate).
- Modulating aromatase (converts androgens to oestrogens) - also resveratrol, I3C, phytosterols
Therapeutic dosage (flaxseed):
25 g / day (providing 50 mg lignans)
Why is it best to consume freshly ground flaxseed?
Unstable polyunsaturated fatty acids.
Oxidise readily if exposed to oxygen, light and heat.
Which drugs may flaxseed interact with?
Anti-diabetic
Additive effects when used with anti-diabetic drugs (can lower blood glucose).
What phytonutrients are in proanthocyanidins
Proanthocyanidins known as condensed tannins formed from
a) Catechin
b) epicatechin
Predominant in seeds and skin of grapes
List FOUR food sources of proanthocyanidins (tannins)
- Grapes (skin and seeds).
- Berries: blueberries, bilberries, elderberries, cranberries.
- Cocoa.
- Apples, cinnamon, cashews.
FOUR headline therapeutic benefits of proanthocyanidins
- CV health
- Immunity ie increase lymphocytes, macrophages and histamine-related, asthma, eczema.
- Neurological ie Parkinson’s and Alzheimers
Proanthocyanidins benefits for cardiovascular health?
- Potent antioxidant properties
- Reduces LDL oxidation.
- Enhances NO, promoting vasodilation.
- Improves circulation and capillary integrity. Protects capillaries from oxidative stress.
Therapeutically used in:
a) Cardiovascular disease prevention.
b) Atherosclerosis.
c) Hypertension.
d) Peripheral oedema.
e) Diabetic retinopathy and neuropathy.
How are proanthocyanidins beneficial in asthma and eczema?
Immune-modulatory properties:
1. Stimulate lymphocyte and macrophage activity.
2. Stabilise mast cells and inhibit histamine-producing enzymes.
How can proanthocyanidins benefit neurological health?
- inhibit beta-amyloid aggregation (Alzheimer’s)
- Parkinson’s by protecting dopamine-producing cells
Which medications should be monitored in the case of supplemental proanthocyanidins?
- Antihypertensive medication.
- Anti-coagulant medications since it may have additive effects.
What colours are anthocyanins and their aglycone (no sugar group attached)?
They are blue, red and purple PIGMENTS.
Potects plants against UV radiation (sun screen)
TWO fruit that are both anthocyanins and proanthocyanidins
- Blueberries.
- Grapes (red)
- Bilberries
- Elderberries
THREE good food sources of anthocyanin
- Acai berry
- Blackcurrant
- Blueberry
- Bilberry
- Cherry
- Red grape
- Purple corn.
How anthocyanins can be therapeutically useful in CV health x4.
- Antioxidant (scavenging ROS) & anti-inflammatory (inhibit NF-kB)= protect against endothelial damage, lower LDL oxidation.
- Improves blood lipids, increases HDLs, ‚lowers LDLs, total cholesterol & triglycerides.
- Decreased arterial stiffness
- Reduces blood pressure.
How anthocyanins can be therapeutically useful in T2DM?
- Improves insulin secretion & increases insulin sensitivity.
- Activates AMPK enzyme, which
a) upregulates GLUT4 (transports glucose into cells)
b) inhibits glucose production in the liver. - Antioxidant & anti-inflammatory - helps protect against diabetic complications incl. retinopathy & neuropathy.
AMP activated kinase = AMPK
How anthocyanins can be therapeutically useful in eye health x2
- Protect ocular tissue from oxidative stress.
- Improves night vision (protects photoreceptor cells).
FOUR nutrients or agents that might help increase insulin sensitivity.
- Anthocyanins
- Alpha Lipoic Acid
- D vitamin.
- Maitake mushroom
- Magnesium
- Myo-inositol
- NACysteine
- Resveratrol
Why anthocyanins useful in neurodegenerative conditions such as Alzheimer’s, Parkinson’s and MND x3?
- Cross blood brain barrier to exert neuroprotective effects.
- Reduce damaging effects of processes that contribute to neurodegeneration ie Oxidative stress, excitotoxicity and glial inflammation.
- Support cognitive performance with improvements in memory and learning.
List THREE types of medications with which anthocyanins may interact.
Increase bioavailability of drugs :
Anticancer agents (mitoxantrone, topotecan, tyrosine kinase inhibitors)
Antibiotics (fluoroquinolones)
Beta blockers (prazosin)
Anticoagulants and high intakes of anthocyanins (e.g. from supplements) increase risk of bleeding.
What food group is resveratrol?
Stilbenoid
List FOUR food sources high in resveratrol
- Red grapes (skins).
- Blueberries, mulberries, raspberries, cranberries.
- Pistachios, peanuts with red skin
- Cocoa
Therapeutic uses for resveratrol?
-
Antioxidant:
a) CV health: Prevents LDL oxidation (antioxidant)
b) Support fertility (e.g. sperm health)
c) Anti-cancer properties - Improves insulin sensitivity and reduces fat accumulation.
-
Oestrogen modulation
Phytoestrogen’. It can inhibit aromatase (reducing testosterone to oestrogen conversation). Oestrogen dominance (e.g. breast cancer)
What is the best time of day to take resveratrol supplements?
Concentration of resveratrol in blood is more bioavailable in the morning
Grape juice is best source.
Resveratrol interacts with anti-coagulants eg asprin.
What are phytosterols? List three good food sources.
Plant-derived lipids that are structurally similar to cholesterol.
Two classes:
1. Sterols
2. Stanols.
Sources:
1. Almonds
2. Brussel sprouts
3. Pistachios
4. Sesame oil
5. Wheatgerm
TWO uses for phytosterols
- Cholesterol reduction
- Prostate health
- Anti-cancer
- Immune health
How are phytosterols useful for lowering LDL cholesterol?
a) Displace dietary cholesterol from micelles (spheres of lipids) decreasing absorption.
b) Disrupt incorporation of cholesterol into chylomicrons impeding transport from enterocytes into circulation.
c) Increasing intestinal clearance of cholesterol.
How can phytosterols benefit prostate health?
- Beta-sitosterol (60-130 mg / day) improves urinary symptoms and urinary flow in patients with BPH.
- Inhibits 5-alpha-reductase and aromatase (reducing formation of DHT & oestradiol which stimulate prostate growth).
Anti-cancer actions of phytosterols x4
a) Inhibits cell proliferation
b) Induces cell cycle arrest and apoptosis
c) Reduces angiogenesis
d) Possible anti-tumour effects by enhancing immune surveillance and detection of cancer cells.
Phytosterols role in asthma and allergies?
Increase TH1 cell activity to down regulate TH2 (TH2-dominance associated with conditions eg allergy, asthma) to re-establish balance where the immune response is Th2 dominant.
x3 sources of phytosterols
POW;
Pistachios
Olive oil
Wheatgerm
- Wheat germ
- Sesame oil
- Pistachios, almonds, macadamia nuts
- olive oil
- Brussels sprouts
- Avocado
- Rye bread
What type of phytonutrient is sulforaphane?
Isothiocyanates (glucosinolates)
Which enzyme catalyses hydrolysis of glucosinolates to form Isothiocyanates?
Myrosinase.
In gut.
Heating destroys it.
Steam it to retain glucosinolates.
THREE functions of isothiocyanates?
- Antioxidant/anti-inflammatory (increases glutathione levels). Anti-chronic diseases.
- Anti-cancer: DNA protection, inhibit angiogenesis, enhance glutathione S-transferase (P2 enzymes involved in carcinogen detox).
- Decreases NF-kB.
Discuss the TWO highly therapeutic compounds found in broccoli sprouts.
- I3C promotes P2 liver detox and is able to support liver’s deactivation of oestrogen (oestrogen dominance eg endometriosis, fibroids, breast and ovarian cancers). 50g per day or supplement.
-
Sulforaphane Induces phase II detoxification enzymes; down regulates phase I enzymes (useful in a liver support protocol).
- Anti-inflammatory (through inhibition of the NF-kB and TNF-a).
- Anti-carcinogenic, through various mechanisms, including:
a) Inducing expression of the tumour-suppressing p21 gene.
b) Induction of phase II enzymes ‚ enhancing detoxification and elimination of activated carcinogens.
c) Increasing antioxidant defense and inhibiting angiogenesis.
What is the major metabolite of I3C?
DIM
In stomach, I3C forms number of biologicallly active indole products (ACV helps to increase acidity for breakdown). Same physiological effects ie DIM and I3C.
Detail the benefits and clinical application of I3C
Oestrogen modulation:
1. Selectively binds to oestrogen receptors acting as an oestrogen antagonist.
2. Influences P1 CYP enzymes to increase conversion of oestradiol to weaker / protective form of oestrogen (2-hydroxyestrone) over 4 & 16- hydroxyestrone (carcinogenic potential).
3. Inhibits aromatase, reducing conversion of testosterone to oestrogen.
Used for fibroids, endometriosis, oestrogen sensitive cancers (e.g. breast) and BPH.
Cervical intra-epithelial neo-plasia (CIN):
1. I3C modulates risk factors for CIN (and in turn, cervical cancer) including elevated oestrogen and heightened inflammation.
2. Reduces activity of the pro-inflammatory NF-kB, reduces cytokines that drive cellular changes.
Breast and prostate cancer:
1. Regulates oestrogen and androgen levels / activity.
- Induces cell cycle arrest, activates tumour suppressor genes, reduces angiogenesis and supports DNA repair.
- Antagonises the effects of dihydrotestosterone (DHT).
What is the best cooking method for retaining the isothiocyanate (ITC) content of cruciferous vegetables?
Steaming - 2 mins.
Stir-frying or boiling cruciferous vegetables for 9~15 minutes has shown to reduce glucosinolate content by 18-59%.
Safety considerations when recommending isothiocyanate supplements or increased brassica vegetables?
- Contraindicated in thyroid health.
*Some glucosinolates degrade to goitrogens: decrease thyroid’s iodine uptake. Ensure good iodine and limit brassica vegetables to 1-2 servings / day. - Safety during pregnancy and lactation not been established.
General therapeutic dosage range of I3C?
How much is one head of cabbage likely to provide?
200-800 mg daily
1200mg
Apart from I3C (and DIM), outline five other ways of supporting oestrogen clearance.
- Optimise soluble and insoluble fibre intake (e.g. whole grains, legumes, nuts / seeds) to bind and excrete oestrogen via bowel.
- Optimise gut microbiome (e.g. probiotics / prebiotics) to prevent de-conjugation of excreted oestrogens.
- Support methylation with folate, B6, B12 rich foods.
- Avoid dairy and oestrogen-mimicking agents e.g. BPA (in plastic, cans), dioxins (eg pesticides), phthalates (eg in cosmetics) ie xenoestrogens.
- Avoid smoking, alcohol and caffeine to avoid over-burdening the liver, preventing it from detoxifying oestrogen.
- (Isoflavines, phytoestrogens, phytosterols… and the others above!)
To which class of phytonutrients do carotenoids belong?
Terpenes.
Source of yellow, orange, and red colours of many plants.
Also in green vegetables.
Explain the therapeutic uses of the carotenoids Lutein and Zeaxanthin in eye health.
- Both carotenoids collect in the macula and absorb upto 90% blue light.
a) Protect retinal cells from oxidative stress.
b) Protect against visual fatigue
c) Lutein promotes efficient neuronal signalling, improving vision.
d) Lutein inhibits NF-kB signalling, reducing inflammation eg uveitis.
e) Support vision and protect against eye strain.
- Age-related macular degeneration.
- Cataracts.
- Diabetic retinopathy.
How much carotenoids in 1 cup of cooked spinach or kale?
3 -20 mg of the two carotenoids (Lutein and Zeaxanthin) combined but much higher lutein.
Carotenoids are fat-soluble; add small amount of fat to increase absorption.
Lightly steaming helps liberate from the cell increasing their bioavailability (also think toms and lycopene). How to eat them?
What is lycopene and which foodstuff is the highest source
Lycopene = fat-soluble red pigment produced by plants. Non-vit A carotenoid.
Tomato = highest source, specifically in paste and puree form.
Name four fruits apart from tomatoes that are good sources of lycopene.
- Guava.
- Pink grapefruit.
- Papaya
- Watermelon.
Anti-cancer benefits of lycopene.
- Antioxidant preventing oxidative damage to DNA.
- Inhibits cancer cell growth.
- Decreases inflammation (which mediates tumour growth) through reductions in COX-2, interleukin-1 and 6 and TNF-a. Inhibits NF-kB.
4.Decreased risk for prostate, breast, cervix, lung, stomach, pancreas and colorectal.
Why lycopene for signs of declining prostate health?
Lycopene naturally accumulates in in the prostate. Intake:
1. Inhibits progression of BPH
2. Decreases elevated PSA.
3. Induces apoptosis
4. Suppresses cell growth in androgen-sensitive cell lines.
How can lycopene be of benefit to Cardiovascular health?
- Lycopene prevents oxidation of circulating LDLs, reducing uptake by macrophages in the arterial wall,
- Reduced plaque formation.
Intake of tomato juice is linked with improvements in endothelial dysfunction.
Which form of tomatoes would you expect to contain the highest amount of lycopene?
Cooked or pureed tomatoes.
Lycopene is better absorbed from foods sources that have been heated or juiced to liberate it from the cell matrix.
Mixing with oils and fats also increases bio-availability.
