Question for the famous Q3W doctors and tnf.
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Guest
Question for the famous Q3W doctors and tnf.
Can you explain to me what do the calories from alcohol actually do? Is it similar to carbs or what? Like a bottle of vodka (750ml) has 1733 calories but zero carbs/fat or protein. It all comes from alcohol. Can someone explain to me what exactly does this energy do?
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Guest
dietary calories will come as proteins, carbs, or fats, and will ultimately all be converted to glucose before they are used for 'energy'.
alcohol metabolism doesn't yield us any direct 'energy', although some NAD is reduced to NADH + H+ ...actually, I am not going to reinvent the wheel here - so here's the info on alcohol metabolism from some site i am about to google:
"
Animal cells contain alcohol dehydrogenase (ADH) which oxidizes ethanol to acetaldehyde. Acetaldehyde then enters the mitochondria where it is oxidized to acetate by acetaldehyde dehydrogenase (AcDH).
Acetaldehyde forms adducts with proteins, nucleic acids and other compounds, the results of which are the toxic side effects (the hangover) that are associated with alcohol consumption. The ADH and AcDH catalyzed reactions also lead to the reduction of NAD+ to NADH.The metabolic effects of ethanol intoxication stem from this action of ADH and AcDH and the resultant cellular imbalance in the NAD+/NADH ratio. The NADH produced in the cytosol must be reduced back to NAD+ via either the malate-aspartate shuttle or the glycerol-phosphate shuttle. Thus, the ability of an individual to metabolize ethanol is dependent upon the capacity of hepatocytes to carry out eother of these 2 shuttles, which in turn is affected by the rate of the TCA cycle in the mitochondria whose rate of function is being impacted by the NADH produced by the AcDH reaction.The reduction in NAD+ impairs the flux of glucose through glycolysis at the glyceraldehyde-3-phosphate dehydrogenase reaction, thereby limiting energy production. Additionally, there is an increased rate of hepatic lactate production due to the effect of increased NADH on direction of the hepatic lactate dehydrogenase (LDH) reaction. This reverseral of the LDH reaction in hepatocytes diverts pyruvate from gluconeogenesis leading to a reduction in the capacity of the liver to deliver glucose to the blood.
In addition to the negative effects of thealtered NADH/NAD+ ratio on hepatic gluconeogenesis, fatty acid oxidation is also reduced as this process requires NAD+ as a cofactor. In fact the opposite is true, fatty acid synthesis is increased and there is an increase in triacylglyceride production by the liver. In the mitocondria, the production of acetate from acetaldehyde leads to increased levels of acetyl-CoA. Since the increased generation of NADH also reduces the activity of the TCA cycle, the acetyl-CoA is diverted to fatty acid synthesis. The reduction in cytosolic NAD+ leads to reduced activity of glycerol-3-phosphate dehydrogenase (in the glcerol 3-phosphate to DHAP direction) resulting in increased levels of glycerol 3-phosphate which is the backbone for the synthesis of the triacylglycerides. Both of these two events lead to fatty acid deposition in the liver leading to fatty liver syndrome."
Now, about the calories in teh bottle of vodka....you are talking just the spirits...not a flavored cocktail or whatever...those calories are, i am guessing, the 'energy' stored within said ethanol...however, it is a mistake to think of ethanol based calories alogn the same lines as protein, carbs, fats...because we don't metabolize ethanol directly for energy. we really can't.
alcohol metabolism doesn't yield us any direct 'energy', although some NAD is reduced to NADH + H+ ...actually, I am not going to reinvent the wheel here - so here's the info on alcohol metabolism from some site i am about to google:
"
Animal cells contain alcohol dehydrogenase (ADH) which oxidizes ethanol to acetaldehyde. Acetaldehyde then enters the mitochondria where it is oxidized to acetate by acetaldehyde dehydrogenase (AcDH).
Acetaldehyde forms adducts with proteins, nucleic acids and other compounds, the results of which are the toxic side effects (the hangover) that are associated with alcohol consumption. The ADH and AcDH catalyzed reactions also lead to the reduction of NAD+ to NADH.The metabolic effects of ethanol intoxication stem from this action of ADH and AcDH and the resultant cellular imbalance in the NAD+/NADH ratio. The NADH produced in the cytosol must be reduced back to NAD+ via either the malate-aspartate shuttle or the glycerol-phosphate shuttle. Thus, the ability of an individual to metabolize ethanol is dependent upon the capacity of hepatocytes to carry out eother of these 2 shuttles, which in turn is affected by the rate of the TCA cycle in the mitochondria whose rate of function is being impacted by the NADH produced by the AcDH reaction.The reduction in NAD+ impairs the flux of glucose through glycolysis at the glyceraldehyde-3-phosphate dehydrogenase reaction, thereby limiting energy production. Additionally, there is an increased rate of hepatic lactate production due to the effect of increased NADH on direction of the hepatic lactate dehydrogenase (LDH) reaction. This reverseral of the LDH reaction in hepatocytes diverts pyruvate from gluconeogenesis leading to a reduction in the capacity of the liver to deliver glucose to the blood.
In addition to the negative effects of thealtered NADH/NAD+ ratio on hepatic gluconeogenesis, fatty acid oxidation is also reduced as this process requires NAD+ as a cofactor. In fact the opposite is true, fatty acid synthesis is increased and there is an increase in triacylglyceride production by the liver. In the mitocondria, the production of acetate from acetaldehyde leads to increased levels of acetyl-CoA. Since the increased generation of NADH also reduces the activity of the TCA cycle, the acetyl-CoA is diverted to fatty acid synthesis. The reduction in cytosolic NAD+ leads to reduced activity of glycerol-3-phosphate dehydrogenase (in the glcerol 3-phosphate to DHAP direction) resulting in increased levels of glycerol 3-phosphate which is the backbone for the synthesis of the triacylglycerides. Both of these two events lead to fatty acid deposition in the liver leading to fatty liver syndrome."
Now, about the calories in teh bottle of vodka....you are talking just the spirits...not a flavored cocktail or whatever...those calories are, i am guessing, the 'energy' stored within said ethanol...however, it is a mistake to think of ethanol based calories alogn the same lines as protein, carbs, fats...because we don't metabolize ethanol directly for energy. we really can't.
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Guest