Westside PUFAs
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- Feb 4, 2015
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January 7th, 2014 noob questions:
Q: How does the body convert fructose consumed from fruits/fruit juice into glucose for the bloodstream?
A: That usually doesn't happen. In the process of energy production, glucose and fructose both go down the same path (glycolysis) to be converted to pyruvate, which is then transferred to the krebs cycle via pyruvate dehydrogenase in the form of Acetyl-CoA. The difference between fructose and glucose is merely that fructose skips the first step of glycolysis, in which glucose is converted to fructose. However, fructose can also stored as glycogen, in which case it would be indeed released as glucose, just to be converted to fructose again during glycolysis.
Q: Some say that starch consumed from potato/rice is insulinogenic because it lacks fructose but how does that fit in with the body using glucose as it's main fuel?
A: As you can probably deduce from the mechanics I explained above, glucose is not really the main fuel of our bodies. All glucose is converted to fructose during energy production (albeit just for a fraction of a second, before it is turned to pyruvate). The reason fructose is not insulinogenic, is that it can enter cells without the help of insulin, while glucose needs insulin to be "pushed" inside of cells. On a sidenote, I don't think that starch or glucose are problematic. They are indeed very necessary for our body, just as insulin is very necessary for our body. Without insulin, you would simply wither away, you would be unable to build any muscles, your pancreas would be slowly destroyed and the structure of cells would fail, as they have to rely on fatty acid oxidation.
Q: Let's say someone eats 3 eggs on an empty stomach with nothing else at all. Why is blood sugar dropped? Why do the amino acids cause a drop in blood glucose?
A: The ingestion of protein causes the body to release insulin, in order to direct the amino acids toward muscle tissue, the brain and other organs. But this also removes glucose from the bloodstream. To counteract this effect, the body releases stress hormones that mobilize glycogen from the liver. Eating carbohydrates with the protein will minimize this effect.
Q: If a person has not consumed any carbohydrate in a few days, how would the body convert some of those three eggs into glucose? Where does the process happen in which some of those amino acids and little fat is converted into glucose?
A: Amino acids are not really converted to carbohydrates in the conventional sense. They are mostly catabolized with the help of different enzymes and enter the krebs cycle at different positions. Every amino acid that enters the krebs cycle as Acetyl-CoA can be turned to glucose and fat. This happens directly at the mitochondria and also occurs if you have eaten carbohydrates.
Q: If someone has a fairly low body fat percentage, and has carefully avoided polyunsatured fat, and we assume that most of the stored pufa is gone from the adipose tissue, when glucose is low, what kind of free fatty acids are released? Are they still unsaturated?
A: The adipocytes have a tendency to withhold saturated fat and release the unsaturated fats in preference. However, this also depends on your endocrine health. Some stress hormones favor the release of unsaturated fats. Normally, you would release PUFAs from your fat cells until you run completely out of them. Then, you would start to release preferably oleic acid, as well as some palmytic and stearic acid.
Q: How does the body convert fructose consumed from fruits/fruit juice into glucose for the bloodstream?
A: That usually doesn't happen. In the process of energy production, glucose and fructose both go down the same path (glycolysis) to be converted to pyruvate, which is then transferred to the krebs cycle via pyruvate dehydrogenase in the form of Acetyl-CoA. The difference between fructose and glucose is merely that fructose skips the first step of glycolysis, in which glucose is converted to fructose. However, fructose can also stored as glycogen, in which case it would be indeed released as glucose, just to be converted to fructose again during glycolysis.
Q: Some say that starch consumed from potato/rice is insulinogenic because it lacks fructose but how does that fit in with the body using glucose as it's main fuel?
A: As you can probably deduce from the mechanics I explained above, glucose is not really the main fuel of our bodies. All glucose is converted to fructose during energy production (albeit just for a fraction of a second, before it is turned to pyruvate). The reason fructose is not insulinogenic, is that it can enter cells without the help of insulin, while glucose needs insulin to be "pushed" inside of cells. On a sidenote, I don't think that starch or glucose are problematic. They are indeed very necessary for our body, just as insulin is very necessary for our body. Without insulin, you would simply wither away, you would be unable to build any muscles, your pancreas would be slowly destroyed and the structure of cells would fail, as they have to rely on fatty acid oxidation.
Q: Let's say someone eats 3 eggs on an empty stomach with nothing else at all. Why is blood sugar dropped? Why do the amino acids cause a drop in blood glucose?
A: The ingestion of protein causes the body to release insulin, in order to direct the amino acids toward muscle tissue, the brain and other organs. But this also removes glucose from the bloodstream. To counteract this effect, the body releases stress hormones that mobilize glycogen from the liver. Eating carbohydrates with the protein will minimize this effect.
Q: If a person has not consumed any carbohydrate in a few days, how would the body convert some of those three eggs into glucose? Where does the process happen in which some of those amino acids and little fat is converted into glucose?
A: Amino acids are not really converted to carbohydrates in the conventional sense. They are mostly catabolized with the help of different enzymes and enter the krebs cycle at different positions. Every amino acid that enters the krebs cycle as Acetyl-CoA can be turned to glucose and fat. This happens directly at the mitochondria and also occurs if you have eaten carbohydrates.
Q: If someone has a fairly low body fat percentage, and has carefully avoided polyunsatured fat, and we assume that most of the stored pufa is gone from the adipose tissue, when glucose is low, what kind of free fatty acids are released? Are they still unsaturated?
A: The adipocytes have a tendency to withhold saturated fat and release the unsaturated fats in preference. However, this also depends on your endocrine health. Some stress hormones favor the release of unsaturated fats. Normally, you would release PUFAs from your fat cells until you run completely out of them. Then, you would start to release preferably oleic acid, as well as some palmytic and stearic acid.
