Intro: Carbohydrates

http://www.thevisualmd.com/health_centers/wellness/nutrition_carbohydrates/what_are_carbohydrates_video

CARBOHYDRATESStructure and Function:

Organic - carbohydrates contain the atoms carbon, hydrogen, and oxygen (C H O)

Each molecule contains 6 carbon atoms, 12 hydrogen atoms, 6 oxygen atoms (C6 H12 O6)

Found mainly in foods from plant sources

Body’s main source of energy - 4 kcal/g

Types of Carbohydrates:1)Simple Carbohydrates (Sugars)

a)Monosaccharides or single sugars

Glucose - AKA “blood sugar” = building block of all other sugars (essential

energy source) Fructose -fruits Galactose -milk products - not found alone/part of disaccharide lactose)

1)Simple Carbohydrates (Sugars): Structure of Glucose

1)Simple Carbohydrates (Sugars): Structure of Fructose

b)Disaccharides - Sugars made of monosaccharides bonded together

Maltose (glucose + glucose) → produced when starch breaks down

Sucrose (glucose + fructose) = granulated or table sugar

Lactose (glucose + galactose) = milk sugar

Structure of Disaccharides:Lactose

Health Concerns: Simple Carbohydrates Health Concerns: “Added Sugars” provide little nutritional

benefit/displace nutrients in the diet Contribute to obesity: Liquid calories

don’t curb our appetite for more food Excess sugars (espec. HFCS) raise the

level of blood triglycerides = a risk factor for heart disease

Recommendations: Limit Added Sugars 10% of total energy (calorie) intake 6.5 tsp a day (females) 9.5 tsp/day

(males)

2 )Complex Carbohydrates Long chemical chains of glucose

molecules = polysaccharidesa) Glycogen: storage form of glucose

in the body (liver and muscle cells)b) Starches: Storage form of glucose in plants Found in wheat, rice, potatoes,

legumes, corn

Complex Carbohydrates: Structure of Starch

Complex Carbohydrates

Health Benefits: “protein sparing effect” (body’s main

source of energy) Weight control – provides increased

satiety and delayed hunger Risk of chronic diseases- cancer, heart

disease, and type 2 diabetes Recommendation: 55% – 60% of total

energy (calories)

Complex Carbohydrates: Fibreb)Fibre – Cellulose, hemicellulose, pectins, gums, lignins

NO ENERGY ↓

– the human body does not produce digestive enzymes capable of breaking fibre into glucose (energy)

Dietary Fibre:

Health Benefits: An important part of our diet as it

assists in the elimination of waste from our body

Aids in weight loss/maintenance - promotes satiety (fullness)

Recommendation: 20g - 35 g/day

Types of Dietary Fibre:

1) Soluble Fibre - dissolves in water Found in fruits (apples, citrus), oats,

barley, legumes Pectin, mucilage, gumsBenefits: delayed glucose absorption (benefits

diabetes) blood cholesterol (benefits heart

disease)

2) Insoluble Fibre

does not dissolve in water found in wheat bran, corn bran, whole

grain breads and cereals, vegetables• Cellulose, hemicellulose, ligninBenefits: Speeds up GI transit (↑ bowel regularity) Associated with reduced risk type II

diabetes

Sugar Overload – 10 Reasons to Cut Back (Nutrition Action Jan/Feb. 2010)

Sugar sweetened beverages promote obesity. Why? Liquid calories don’t curb our appetite for more food

Sugar Sweetened drinks may raise the risk of heart disease.

Why ? Excess sugars (espec. Glucose fructose) raise the level of

blood triglycerides = risk factor for heart disease

Fructose may promote overeating. Why? By blocking the leptin (appetite control) signal to your brain

telling you to stop eating

The Bottom Line: Most sugary foods are junk!

Added Sugar- How Much are you consuming? 1 can Coke/Sprite/Pepsi = approx 10 tsp

added sugar 1 bottle Vitamin Water Essential = 9 tsp

added sugar 1 bottle Arizona Green ice tea = 10 tsp

added sugar

Recommendations for Added Sugar Intake: Women: 6.5 tsp/day Men: 9.5 tsp/day