CARBOHYDRATES Not the evil we’re led to believe

What are carbohydrates? Carbo-hydrate means carbon and water (C + H 2 O). For every carbon there is 1 water molecule or 2 hydrogen atoms and 1 oxygen atom. 2 categories: Simple carbohydrates = Complex carbohydrates =

Where do carbohydrates come from? Plants and photosynthesis Except for galactose, which comes from milk

Carbohydrates Sugars (saccharides Monosaccharides (single sugars – one molecule) Glucose – the basic fuel for our bodies Fructose – found in fruit Galactose – found in milk Why is it better to ingest sugar in fruits than as refined sugar?

Carbohydrates Sugars cont’d Disaccharides (two sugars joined together) Sucrose – glucose + fructose, table sugar & honey. Maltose – glucose + glucose, found in grains. Lactose – glucose + galactose, found in milk.

Carbohydrates Polysaccharides (means many sugars or 3 or more sugars) Complex Carbohydrates Fiber – Soluble fiber – dissolves in water and is digestable. Insoluble fiber – does not dissolve in water, less digestable

Carbohydrates used by Man Polysacchrides cont’d Fiber – Soluble fiber – dissolves in water and is digestable. Insoluble fiber – does not dissolve in water, less digestable.

Do we really need carbohydrates? Glucose is the preferred fuel for many of our cells including our brain and the rest of the nervous system. Carbohydrates (includes fiber) often occur in food (fruits and vegetables) with water, vitamins, minerals, phytochemicals, and no fat. They are also relatively cheap!

Do we really need carbohydrates? Carbohydrates and weight loss: carbohydrates have fewer calories per gram than fat. Trick: eat in moderation and use complex carbohydrates, not refined sugars. Refined sugar recommendations: no more than 12 tsp/day, less than 10% of calorie intake, Table 4.1. The average current intake in American is 31 tsp/day.

Why fiber? Decreases the risk of cardiovascular diseases: binds cholesterol and bile, and decreases our intake of fatty foods by making us feel full Helps control blood glucose

Why fiber? Improves health of digestive tract: stimulates muscles (digestive tract muscles need exercise too!, prevents constipation, appendititis and formation of diverticuli Colon cancer and fiber: Older studies have shown that diets that provide adequate fiber prevent colon cancer. New studies shows that fiber supplements do NOT prevent colon cancer. i.e. Eat your fruits and veggies because they seem to have phytochemicals that prevent cancer.

Digestion and Absorption of Carbohydrates Blood carries monosaccharides to the liver. Glucose is absorbed directly into the blood stream – no digestion required. All carbs are converted to glucose. Glucose travels to other cells via the blood. Extra glucose is stored as glycogen in the liver and skeletal muscles.

How do our bodies use glucose? In the absence of glucose our bodies use protein (muscle tissue) as fuel. Fat is also potential fuel but requires carbohydrates to be used properly. Without carbs, fat breakdown is incomplete and produces ketosis. Ketosis – causes the body fluids to become more acidic and this dissolves bone, promotes kidney stones, bad breath, high cholesterol, high blood pressure, even death.

How to Read the Carb Label o See the total Carbohydrates for this label? o 31 grams o Dietary fiber is 0 grams o Sugars account for 5 grams o If the dietary fiber was 5 grams – we could deduct 5 grams from the 31 for a total of 26 carb grams. o Why can we deduct fiber?