Nutrition 1 - Macro Nutrients Flashcards
Carbohydrates; groups
The preferred source of energy by the body. Includes starches (bread, pasta etc), cellulose (plant fibre), and sugars.
Three main categories:
1. Single sugars (monosaccharides)
2. Double sugars (disaccharides)
3. Complex carbohydrates (polysaccharides)
Carbohydrates:
1. Single sugars (monosaccharides)
Single sugars (monosaccharides):
* Glucose (key energy source)
* Fructose – fruit sugar
* Galactose – milk sugar
Carbohydrates:
2. Double sugars
(disaccharides
Double sugars (disaccharides)
Sucrose – sugarcane (glucose + fructose)
Lactose – milk sugar (glucose + galactose)
Maltose – brains (barley) (glucose + glucose)
Carbohydrates:
3. Complex carbohydrates (polysaccharides)
Complex carbohydrates (polysaccharides)
* Starches – found in foods such as bread, rice, pasta (grains), vegetables, legumes etc
* Cellulose – the structural material plants (found in plant walls) and provides dietary fibre
* Complex carbohydrates:
o Retain their rich nutrients
o Are digestive more slowly, promoting satiety and help to keep blood glucose in balance
Refined carbohydrates
Refined carbohydrates (e.g. sweets, white bread) are carbohydrate that have been processed & stripped of their important nutrients. These lead to:
* A lack of nourishment
* Tooth decay
* Lower energy levels/fatigue
* Blood sugar imbalances
* Insulin resistance and type II diabetes
* Weight gain, obesity
* A weakened immune system; they deplete cells of vitamins C
* Poor bowel health and constipation (due to lack of fibre)
Therefore you should focus on complex carbohydrates
Carbohydrates: unrefined carbohydrates list
Unrefined/wholegrain – complex carbohydrates:
* Wheat, rice, oats, barley, rye, millet, buckwheat, spelt, kamut, quinoa, teff
* Whole – bread, pasta, noodles
* Legumes, beans, lentils, peas, nuts, seeds
* Vegetables, fruit
* Honey (some) e.g. manuka, raw (unpasteurized) honey
Carbohydrates: refined carbohydrates list
Refined Carbohydrates stripped of most nutrients:
* White – cereals, flours, rice, barley
* White – b read, pasta, noodles
* Pastries, cakes, biscuits, sweets
* Chocolate, crisps, pizza
* Fizzy drinks, sugar, honey, jam
Fibre
Fibre is a complex carbohydrate that originates from plant cell walls that cannot be digestive by the human.
Benefits:
* Aids the movement of food through the digestive tract, increase stool bulk – prevents constipation
* Lowers the risk of diverticulitis and colon cancer
* Reduces absorption of dietary cholesterol and slows glucose absorption (preventing spikes in insulin)
* Reduces the risk of cardiovascular disease / type II diabetes
* Weight control–fibre increases satiety– Feel fuller for longer
* Feed the microflora, resulting in numerous health benefits (fermentation of some fibre in colon by healthy bacteria produce short chain fatty acids = fuel source for colon cells, reduces inflammation, effects throughout whole body such as blood glucose control, cholesterol moderation)
Soluble fibre
Soluble fibre dissolves in water. (also referred to as fermentable fibre – produce short chain fatty acids)
* Attracts water in the body to form a gel
* Slows digestions and regulate blood sugar (reduces absorption of dietary cholesterol)
* Has a filling (satiating) effect
Good sources includes: oats, legumes, apples, oranges, pears, strawberries, nuts, flaxseed, psyllium, cucumbers, celery, carrots
Insoluble fibre
Insoluble fibre does not dissolve in water
* Helps move waste through the intestines, encouraging regular bowel movements
Good sources include: whole grains, bran, seeds, nuts, carrots, cucumber, cabbage, onion, courgette, celery, dark leafy greens
Proteins: Function
Proteins are formed of amino acids, which act as the building blocks for proteins. Proteins function to:
* Provide body tissue structure e.g. in skin, bones, blood vessels, hair
* Provide movement (e.g. muscles)
* Carry substances (e.g. haem meoglobin – oxygen)
* Act as enzymes (e.g. digestive enzymes)
* Form hormones (e.g. insulin)
* Provided immune defense (e.g. antibodies)
* Provide alternative energy source (less efficient than carb/fats)
Protein in Greek = ‘or first importance’
Amino acids
Proteins are formed of amino acids, which act as the building blocks for proteins. The human body commonly uses 20 amino acids. Amino acids (AAs) are divided into:
1. Non-essential amino acids: produced by the body, not required in the diet
2. Essential amino acids (nine of them): not produced by the body, must be in the diet
3. Conditionally essential amino acids: some non-essential AAs become conditionally essential in certain circumstances, e.g. at certain ages or during diseases
The essential amino acids are: histadine, leucine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine
Proteins: complete
Complete protein:
* Food that contains all nine essential amino acids (AAs)
Proteins: incomplete protein
Incomplete protein:
* Food low in one or more of the essential AAs
* Most plants foods have an incomplete protein profile – one or more essential AAs are missing (commonly either methiomine or lysine)
* A varied vegan diet delivers all necessary AAs. The quality/digestibility of protein from food is more important than the amount of protein eaten
Plant proteins (complete)
Plant proteins are affordable, delicious and easy to obtain from vegan food. They also have additional nutritional value such as fibre and phytonutrients.
* When properly prepared they are easily utilised by the body
* Associated with decreased risk of many chronic conditions
Examples of vegan foods containing all nine essential AAs:
* Quinoa – gluten-free and versatile
* Buckwheat – not actually wheat
* Pumpkin seeds
* Chia seeds