Nutrient #1: Carbohydrates

NOT JUST BREAD!

Carbohydrates Body’s most important source of ENERGY because it is used quickly Make up the largest component of most diets (60% of daily calories) Plants are our primary source (potatoes, bread, corn, rice, and fruit) Energy + Carbon dioxide + WATER GLUCOSE + OXYGEN E + CO2 + H2O C6H12O6 + O2 **PHOTOSYNTHESIS gives us carbohydrates!

Where does the word CARBOHYDRATE come from? CARBO: from the CARBON that every carbohydrate contains HYDRATE: is from the WATER that every carbohydrate contains The ratio of carbon to water is 1C: 1 H2O for any type of carbohydrate

Carbohydrates: Structure Carbohydrates are made up of either single sugar molecules or chains of several sugar molecules.

Types of Carbohydrates Monosaccharides (simple sugars)  Mono means “one”  Saccharide means “sugar” Examples: - GLUCOSE (C6H12O6): IMMEDIATE source of ENERGY, found in ALL disaccharides - FRUCTOSE: found in fruit, tastes very sweet - GALACTOSE: found in milk, not as sweet - DEOXYRIBOSE: found in DNA **Note: Sugars on food labels are recognized by “ose” endings

Same chemical formula, yet different structures and different tastes! C6H12O6 C6H12O6 Same chemical formula, yet different structures and different tastes! C6H12O6

Types of Carbohydrates 2. Disaccharides (two single sugars combined) “Di” means two Two simple sugars combine via dehydration synthesis (water is removed) Opposite is hydrolysis (water is added) Examples: -MALTOSE: glucose + glucose (used in beer) -SUCROSE: glucose + fructose (table sugar) -LACTOSE: glucose + galactose (sugar in milk)

Maltose molecule C12H22O12 Removal of water = dehydration Glucose

Sucrose molecule C12H22O11 Removal of water = dehydration

Lactose molecule C12H22O11 Lactose Removal of water Glucose = dehydration Glucose Galactose Lactose

Types of Carbohydrates 3. Polysaccharides (Complex carbohydrate)  “Poly” means many Polysaccharides Starch Cellulose Glycogen

Types of Polysaccharides Starch Can contain between 2,000 and 6,000 glucose molecules Used by plants as storage for energy (in roots and stems) –broken down into single sugar molecules for use by cells as needed Grain or wheat products (bread and pasta), potatoes and vegetables are good sources

Types of Polysaccharides b) Cellulose Found in cell walls of plants (structure) Similar to starch, but bonding between glucose molecules is different so we can’t digest it CELLULOSE = (insoluble) FIBRE Good sources: vegetables and seeds

Types of Polysaccharides c) Glycogen Type of energy storage in animal cells Reserve energy, polymer of glucose! Stored in liver and muscle cells Resembles structure of starch, but has more branching

Too many carbohydrates in your diet… Glycogen stores become saturated (full) The excess glucose (simple sugars) still need to be stored somewhere… They are converted to FAT for energy storage!!!

How Much Sugar is in Our Favourite Foods? http://www.sugarstacks.com/snacks.htm