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Name: shahram
Status: N/A
Age: 50s
Location: N/A
Country: N/A
Date: 2000-2001


Question:
I have read in a scientific journal something to the effect of "everything we consume as food is converted into glucose by the body before absorbed- (that is all fats, carbohydrates and proteins)"- is this statement true?, if yes why are we so obsessed by our consumption of different kinds of fats, should we not concentrate more on how glucose is metabolized (absorbed) in the body.


Replies:
It is NOT true. It could hardly be further from the truth for numbers of reasons. The simplest reason I can think of is that all life forms we know of contain considerable amounts of Carbon Hydrogen Oxygen Phosphorus and Sulfur. In our nutrition we have to take these in to grow and survive. Glucose is composed of only Carbon, Hydrogen and Oxygen. Additionally, there are a wide number of what are called micronutrients that we have to have in our diet to survive such as magnesium, iron, iodine etc... so where do we get the rest of these elements? Maybe we have stars inside our intestines and we make all the heavier elements...just kidding (8 Beside the elments issue we also cannot make certain molecules such as certain oils called fatty acids these essential fatty acid must be in our diet or we become ill and/or die. We also have a series of essential amino acids which we need in our diet.

Now on the other hand what the article might have tried to say was that glucose is the major source of energy for humans... which is border line true but still a gross overstatement. Many of our cells energy sources are glucose but they can also work on fatty acids and amino acids. Many of our genes exist to produce the enzymes that allow lipids (fatty acids), proteins, and carbohydrates to be used for energy depending on what is available.

Peter F


Actually, all substances are broken down into glucose, glycerol and fatty acids (fats) and amino acids (for simplicity's sake) but fats and protein CAN be converted to glucose if needed. The body's first need is for energy to run itself and that only comes from glucose. In a starvation scenario, the first substance used for energy is glucose. When that runs out, carbohydrate stores (starch) is broken down to glucose. Then when that runs out, fats are converted to glucose. When fat runs out the body begins to break down protein in a process known as gluconeogenesis. When 1/3 (I'm not sure of the exact amount) of the body's protein is gone, death follows shortly.

Van Hoeck


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