Non-nutrient content of food Flashcards
What are some examples of non-nutrient components of food?
- Alcohol
- Caffeine
- Anti-nutrients
- Polyphenols
- Nitrates
- Phytosterols
- Carotenoids
- Additives
What are non-nutrient components?
Anything that has an impact on health but isn’t a nutrient
What is the guideline intake for alcohol
14 units per week spread over 2-3 days - for both men and women
No more than 5% total dietary energy.
How much is 1 unit of alcohol
10ml or 8g pure alcohol
Units = volume of drink x (%/100)/ 10
e.g 25ml of 40% spirit = 25 x 0.4/ 10 = 1 unit
What effects how alcohol is removed from the blood?
And what is the average rate?
1 unit/ hour
Varies on:
- Size
- Sex
- Metabolism
- Condition of liver
What is the safe limit for people to drive after drinking alcohol in england?
80mg/ 100ml blood or 0.8% BAC
It is difficult to be sure alcohol has been metabolised.
Can you speed up alcohol metabolism
No!
What is a superfood?
Very rich is phytochemical and polyphenols
Have big health claims
Often just a marketing claim
What are some examples of phytochemicals?
Phenolics Carotenoids Flavonoids Phytosterols Nitrogen containing compounds Alkaloids
What are phytochemicals?
Biologically active compounds found in plants
What are the benefits of pyhtochemicals?
Protect cells from damage that could lead to cancer
Help stop carcinogens attacking cells
What are flavonoids found and what do they do in the body?
They are found in grains, vegetables and fruits.
The flavonoids found in chickpeas and soybeans act like estrogen, which can help reduce risk of breast cancer.
Where are carotenoids found and what is their benefit?
They are found in carrots, sweet potato, cantaloupe, squash and apricots.
Help reduce risk of cancer.
What foods contain sulfides, and what is their benefit?
Found in garlic and onions
Can help strengthen immune system.
What are antioxidants?
What food sources contain them?
Free radical cells
Unstable molecules created during normal cell functions.
They are found in broccoli, brussel sprouts, tomatoes, cauliflower, carrots, sweet potatoes, soybeans, spinach, liver, fish oil, kale, beets, red pepper, blueberries, strawberries, black and green tea, mangoes…
Dark colour fruits and veg are more antioxidant rich
How many different plant foods should be eaten per week?
30
What is caffeine?
Natural pesticide
Stimulant - stimulates CNS
Mild diuretic
Most widely used unregulated drug
Effects sleep quality, even for those who can sleep after caffeine intake
Ergogenic aid - used for performance in athletes
What is the half life of caffeine?
5-6 hours
What are the guidelines for caffeine?
Adults - single doses of 200mg, daily intake of 400mg
Pregnancy - daily intakes of up to 200mg
Children - single or daily doses up to 3mg/kg body weight
What can long term excessive consumption of caffeine cause?
Increased heart rate Raised blood pressure Jitteriness Stomach upset Headaches Addiction - without struggle with energy levels
Are there any benefits of caffeine?
Some links with decreased mortality
Contains polyphenols that can have health benefits
What foods contain dietary nitrates and nitrites?
Nitrates NO3-
- Vegetables and fruit - beetroot, spinach, rocket, lettuce, leeks
Nitrite NO2-
- Cured and processed meats - bacon, ham, hot dogs
Where are nitrates absorbed?
The gut
What can reduce nitrate to nitrite?
Bacteria in the oral cavity
What bodily function does nitric oxide have an impact on?
Vasodilation and cardiovascular health
What are the risks of heating nitrites to high temperatures?
Can form some carcinogenic compounds which can influence gut health and create a risk of cancer.
This is why some products may say they’re nitrite free
What are the benefits of nitrates on the cardiovascular health?
- Decrease risk of CVD
- Decrease blood pressure
- Decrease risk of heart attack
- Decrease inflammation
- Vasodilation
- Increase oxygen to working muscles
- Decrease platelet aggregation
Why are nitrates an ergogenic aid?
- Increase oxygen to working muscles
- Decrease oxygen cost of exercise
- Improve tolerance and performance
What phytochemical has a similar structure to cholesterol?
Phytosterols
Plant stanols
Plant sterol esters
How can plant sterols reduce amount of cholesterol absorbed?
They compete with cholesterol for enzymes.
Have a hypocholsterolaemic action - similar structure causes them to compete
What cholesterol can plant sterols reduce?
LDL cholesterol
What are plant sterols sometimes added to?
Vegetable oils and spreads
What is Lycopene?
And where is it found?
Bright red carotenoid
Found in tomatoes and other ref foods
What are some benefits of Lycopene?
Protect against skin damage
Improved heart health
Reduce risk of certain cancers
Promote good oral and bone health
What is an anti-nutrient?
Something that impairs absorption of certain nutrients - restrict bio-availability of key nutrients
What are some examples of anti-nutrients?
- Phytates - inhibit iron, zinc and calcium absorption
- Oxalates - inhibit calcium absorption, increase calcium kidney stone formation
- Lectins - alter gut function
- Phytoestrogens - endocrine disruption, increase risk of estrogen sensitive cancers
- Tannins - inhibit iron absorption, negatively impact iron stores
- Goitrogens - inhibit iodine uptake
When might oxalate impair calcium absorption?
When there is an inadequate intake of calcium.
Why should tea be avoided when eating a meal?
Can effect iron absorption from that meal
What is the average consumption of polyphenols?
1g/day
Where are polyphenols absorbed
90% enter large intestine and are catabolised by colonic microbiota
What are flavonoids?
Phenolic compounds with antioxidant properties.
Over 9000 known
What are sources of flavonoids?
Anthocynins - berries, cherries, red cabbage
Flavonols - onion, broccoli, beans
Catechin - green tea, chocolate
Proanthocyanidins - cocoa, cider, wine
Flavanones - citrus fruits, tomatoes, mint, herbs
Isoflavones - soya
Why are soybeans complete proteins?
Contain all 9 essential amino acids
What is resveratrol?
Where is it found?
Antioxidant
Has anti-inflammatory effects
Found in red wine
Associated with reduction of morbidity and mortality from CVD, lung cancer, prostate cancer and alzheimer’s disease.
What are some adverse effects of polyphenols?
May interfere with pharmaceutical agents
Supplementation/ fortification not recommended - more research
Toxic effects, potentially if taken in large amounts
Induce DNA strand breakage - carcinogenic
Pro-oxidant - tissue damage
What are E numbers?
Additives approved by the EU
Why might additives be added?
- To prevent bacterial growth
- Prevent rancidity
- Prevent food drying out
- Emulsification
