Agent Intellect
Absurd Anti-hero.
Having always had an interest in nutrition, and now having taken an Advanced Nutrition and Human Metabolism class last semester (as well as having some other Biochemistry and Physiology classes under my belt), I've decided I'm going to do a series on nutrition on my Facebook community page if anyone is interested.
I've already made a lengthy post there a while back on the affects of alcohol on the body for new years which is similar to how my nutrition posts will be. I'll repost this here:
Original.
I've already made a lengthy post there a while back on the affects of alcohol on the body for new years which is similar to how my nutrition posts will be. I'll repost this here:
The Cynical Philosopher said:
New Years Eve is considered one of the biggest drinking holidays of the year (along with the night before Thanksgiving, Cinco de Mayo, Saint Patrick's day, Mardi Gras, Oktoberfest... well, people just don't need too much of an excuse to drink).
So, while you nurse your hangover from last night with whatever remedy you've found on some bullshit website, you can read here about what actually happens with alcohol in your liver.
The ethanol is first oxidized by an enzyme called alcohol dehydrogenase, using a coenzyme called NAD+ (made from niacin, or vitamin B3) which turns it into NADH and results in a chemical called acetaldehyde. Acetaldehyde is somewhat toxic and is thought to be one of the culprits in most of the shitty hangover symptoms, along with lactic acid buildup, dehydration/electrolyte imbalance and impurities in the alcohol (the reason cheap liquor often gives worse hangovers). Acetaldehyde is then further oxidized by acetaldehyde dehydrogenase using another NAD+ to NADH and results in acetate (conjugate base of acetic acid - the stuff in vinegar).
Alcohol oxidation:
http://sciblogs.co.nz/misc-ience/files/2010/03/alcohol-oxidation.jpg
Many Asian people have a variant of alcohol dehydrogenase that catalyzes the reaction of ethanol to acetaldehyde much faster than the normal variant, allowing them to drink more alcohol while getting less drunk (so don't get into a drinking contest with an Asian person) but often resulting in what's called the alcohol flush reaction. Of course, this also means that they are more prone to the diseases that result from alcoholism since acetaldehyde builds up quicker.
Alcohol Flush Reaction:
http://en.wikipedia.org/wiki/Alcohol_flush_reaction
Some problems arise even after acetaldehyde is metabolized into acetate. The acetate is converted into acetyl-CoA (CoA is coenzyme A, made from pantothenic acid aka vitamin B5), which is usually brought into the Kreb's cycle by doing a 1-to-1 reaction with another metabolite called oxaloacetate. Since there is more acetyl-CoA than oxaloacetate now (which must be made either from glucose metabolized to pyruvate or a round in the Kreb's cycle) the acetyl-CoA builds up and is then shuttled into fatty acid production. This results, obviously, in the buildup of fat, and in chronic alcoholism eventually results in fatty liver disease and cirrhosis.
Kreb's cycle:
http://www.uic.edu/classes/bios/bios100/summer2003/krebs-cycle.gif
Fatty acid synthesis:
http://www.biology-direct.com/content/figures/1745-6150-4-8-2-l.jpg
Alcoholic Liver Disease:
http://en.wikipedia.org/wiki/Alcoholic_liver_disease
There is another problem. All the NADH that was made earlier needs to be recycled. Because NADH accumulates, the reverse reaction of transamination of glutamate to alpha-ketoglutarate in the Kreb's cycle is favored, causing glutamate to accumulate and decreasing the oxaloacetate concentration mentioned above and therefore impairing gluconeogensis, which is needed to mobilize glucose from the liver when blood glucose gets low. The NADH has to be recycled through fermentation, causing lactic acid to buildup (the stuff the causes sore muscles after exercise).
Fermentation to Recycle NADH back to NAD+
http://www.rpi.edu/dept/bcbp/molbiochem/MBWeb/mb1/part2/images/lactate.gif
Transamination of glutamate to alpha-ketoglutarate:
http://david-bender.purplecloud.net/metonline/aaN/transam/images/transdeam1.png
But, there is another way that the liver can metabolize alcohol. It's called the Microsomal Ethanol Oxidizing System, or MEOS (contains CYP2E1 aka Cytochrome P450 2E1). This is the oxidizing system that increases with drinking, increasing your tolerance to alcohol - the reason heavy drinkers can drink so much. It's also the system in the liver that oxidizes many drugs (xenobiotics), such as Tylenol and acetaminophen. When concentrations of alcohol are high in the body, such as when drinking, the ethanol is preferably metabolized by the MEOS, resulting the drugs sitting in the liver and causing damage. This is why you are not supposed to take medicines like this while drinking as this damage can lead to liver failure. MEOS still results in the accumulation of acetyl-CoA so it does not prevent liver disease in chronic alcoholics.
Microsoman Ethanol Oxidizing System:
http://themedicalbiochemistrypage.org/images/cyp2e1-activities.jpg
The picture with this post is somewhat incorrect. B vitamins will not speed metabolism of alcohol, but alcohol does decrease B vitamin levels, particularly thiamin (vitamin B1) which is used in the form of thiamine pyrophosphate (TPP) in various enzymes needed for sugar (and fat) metabolism and is needed for nervous system health. Alcoholics often have low vitamin B1 levels, which can lead to diseases such as Korsakoff's syndrome and beriberi.
Korsakoff's Syndrome:
http://en.wikipedia.org/wiki/Korsakoff%27s_syndrome
Beriberi:
http://en.wikipedia.org/wiki/Beriberi
There is no great remedy for a hangover except not drinking in the first place. Getting plenty of water and electrolytes before, during, and after consuming alcohol can help with symptoms from dehydration. Drinking higher quality liquor and clear liquor is usually better for avoiding the impurities that can cause hangovers.
Hope you all are having an adequate New Years.
Original.
