Why the conventional diabetes diet is wrong
A background of dietary nonsense
If you aren't convinced or are confused, let's look at the British Dietetic Association's advice in more detail. This tells us all to base meals on starchy foods like bread, pasta, breakfast cereals, et cetera; 'eat five portions of fruit and vegetables a day'; and to cut down on sugary foods. Let me explain why I call this dietary nonsense:
'Cut down on . . . sugary foods'
This is one admonition that I don't disagree with. But I want to show you how it fits into a pattern of dietary nonsense.
The chemical name for sugar - the white granulated stuff you put in your tea - is sucrose. Sucrose is a disaccharide, which means two sugars. Its chemical formula, C 12 H 22 O 11 , means that it is made up of twelve atoms of carbon, twenty-two atoms of hydrogen and eleven atoms of oxygen. When it is digested, it enters the bloodstream as the blood sugar, glucose, whose formula is C 6 H 12 O 6 . In this process one molecule of C 12 H 22 O 11 ends up as two molecules of C 6 H 12 O 6 . But you will notice that sucrose has only 22 hydrogen and 11 oxygen atoms, before it can become glucose, it must gain 2 hydrogen atoms and one oxygen atom somehow. It does this very simply by combining with water whose chemical formula is H 2 O (which means it has two hydrogen atoms and one oxygen atom - exactly what we need). The process is illustrated thus:
C 12 H 22 O 11 + H 2 O => C 6 H 12 O 6 + C 6 H 12 O 6
1 Sucrose + 1 Water => 2 glucose
The addition of the water molecule to the sugar molecule increases the total energy content. In this way, 100g of sugar, which you would think contains 400 kcals, ends up as 105g of glucose or 420 kcals.
'Base meals and snacks on starchy foods'
The situation is similar with starches. Dieticians call starches 'complex carbohydrates' or polysaccharides , which means many sugars. Our digestion also converts these into glucose but, in this case, the formula is a little different. Starch is made up of strings of thousands of sugar molecules fastened together. The formula for each of these individual sugar molecules is C 6 H 10 O 5 so, to make it into C 6 H 12 O 6, , it again needs to find two hydrogen atoms and one oxygen atom. So one molecule of water, H 2 O, is combined with each of the starch sugars. In this way:
C 6 H 10 O 5 + H 2 O => C 6 H 12 O 6
Starch + Water => glucose
But as the atoms from the water now form a greater proportion of the total in this equation, 100g of starch actually become 111 g of glucose or 444 calories. That's more than the sugar!
So if you are taking DiabetesUK's advice for weight loss and trying to reduce your calorie intake, basing meals on starchy foods doesn't look like a very clever thing to do.
And the second piece of advice appears to be no more sound:
Q: What are diabetics told to eat?
A: "5 portions of fruit and vegetables a day"
Q: What carbohydrate do fruit and vegetables contain?
A: FRUCTOSE - which is a sugar!
Ah, yes . . . but . . . glucose raises blood levels very quickly (Fructose is preferred to glucose because it is thought to take longer to raise blood sugar).
In which case . . .
Earlier I lied . . . well didn't tell the whole truth. You see C 6 H 12 O 6 is the formula for both glucose and fructose
Sucrose hydrolyses to 50% glucose and 50% fructose. In other words, table sugar is half fructose . . .whereas starch hydrolyses to glucose alone.
Using their argument, wouldn't that make sugar healthier than bread?
You see now, I hope, why I call it nonsense!
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