Carbs 101 & 102

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hanadr

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I've posted variations on this in various threads, but since questions come up regularly(and I worked hard on it) I thought it might be useful to have it under its own header.
[u]Here goes Carbs101[/u]
A carbohydrate is a molecule made up of atoms of carbon, hydrogen and oxygen bonded chemically. The proportion of hydrogen to Oxygen is usually, but not always 2:1. Among the simplest carbohydrates are the simple sugars, or monosaccharides. They have a carbon chain spine, which often forms a ring, with hydrogen and a group which is the “free sugar" group attached. Simple sugars with carbon chains of from 2 to 10 carbon atoms are known. If 2 monosaccharides are chemically bonded together, a disaccharide is formed. thus Glucose and fructose, with a 6 carbon and a 5 carbon ring respectively, both monosaccharides combine to form sucrose, a disaccharide. Polymers of many monosaccharide units include, starch and cellulose.
The only carbohydrates of importance in the diabetic diet are those based on, or easily converted to glucose. This does not include fructose. Fructose is Very sweet and tastes nice, but tends to encourage formation of triglycerides in the liver. This is a pity.
For every molecule of Sucrose (table sugar) you consume, only half becomes blood glucose.. The other half is fructose and is metabolised along different pathways. However, for every molecule of starch you consume, 100% becomes blood glucose. Thus effectively, starch is worse for blood glucose levels than table sugar, weight for weight.
The so-called complex carbs, tend to be made up of starches and some cellulose (which is also a carb, but not digestible)
A whole heap of cellulose, otherwise known as dietary fibre, won't raise your BG, but a whole load of starch WILL.
To make remembering all this more difficult, there are 2 kinds of starch chains, Amylose and amylopectin.
Amylose is formed of straight chains, which coil up tightly and resist cooking
Amylopectin is formed of branched chains, which are loosely wound.
We don’t have a mechanism for digesting starch in the raw state, it must be cooked first. So starches containing a lot of amylose in the mix are slower to digest, the so called low GI starches.
Although, amylose will be broken down 100% into glucose, it happen slowly.
Typical starches contain about 20% amylose and 80% amylopectin. Starches from different plant sources vary somewhat.
Unless you want to study biochemistry, a good way to remember which carbs to eat, is Sugar goes 50% to BG FAST
Starch goes 100% to BG Slower.
The only truly GOOD carb for a diabetic is Cellulose, which we can’t digest at all. It’s dietary fibre, or roughage and keeps the gut working, giving it something to push on.l
 

sugarless sue

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Re: Carbs 101

Hana ,I'm going to make this a 'sticky' in the food forum before it disappears off the board again!!
 

hanadr

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Here it is! next part Carbs 102

Carbs 102
“What’s in a name? that which we call a rose, by any other name would smell as sweet”
Sugars hide by other names.
There’s an organisation called the IUPAC(International Union of Pure and Applied Chemistry) Part of whose function is to give unambiguous names to molecules.
Their rules ensure that the “bicarb” in your baking powder is properly called Sodium Hydrogen Carbonate.
Each part of the name tells you something about it
If it ends in ~ose, it’s a sugar or sugar polymer. The rest of the name also conveys information
A triose, is a sugar built on a 3 carbon chain. Similarly, a tetrose on 4, a pentose on 5 and a hexose on 6.All the way up to the decoses. Glucose is a hexose.
Monosaccharides,( simple sugars) link chemically into bigger molecules, whose names may show where they came from
Examples are:- lactose, from milk, maltose, from malting barley
There are several long chain polymers of monosaccharides. Starch is a polymer of glucose, whose chains may be many hundreds or thousands
of monomers long.
Other sugar polymers include glycogen, cellulose and chitin
The important point of all this biochemistry (other than making me go to books I have left on the shelves for decades), is to show how cunningly the food manufacturers hide sugars in their products.
If an ingredient’s name ends in ~ose, it’s a carb, probably a sugar
Trouble is that many names remain that were in use before IUPAC rules were made up.
One particularly sneaky one is “high fructose corn syrup” this stuff is made from starch which is treated to break it down into its glucose and fructose units
Starches have no sweet taste, but this stuff does. It’s similar in sweetness and components to sucrose ( table sugar, cane sugar, beet sugar)
That’s another clue to the presence of sugars. The taste!
Unless a non-carb sweetener is listed on the ingredients, a sweet taste tells you some sugar is present.
Diabetics need to know which foods will break down into blood glucose. Also how to read the nutrient information panel on food packaging.
I’ll simplify this lecture into
“WATCH OUT for ~Oses,
 
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