alcohol asian aziaten diet echobunny etc flush health life madcow science

My tags:

From Wikipedia, the free encyclopedia

Alcohol flush reaction (Asian Flush, Asian Glow, Red Cheeks, Oriental Flush, Big Blush) is a condition in which the body cannot break down ingested alcohol completely, due to a missense polymorphism that encodes the enzyme, acetaldehyde dehydrogenase (ALDH2) ^[1], normally responsible for breaking down acetaldehyde, a product of the metabolism of alcohol.^[2] Flushing, or blushing, is associated with the erythema (reddening caused by dilation of capillaries) of the face, neck, shoulder, and in some cases, the entire body after consumption of alcohol.

Research has shown that a history of facial flushing when drinking is indicative of ALDH2 deficiency, and that a ALDH2-deficient drinker has 6 to 10 times the risk of developing esophageal cancer as a drinker not deficient in the enzyme.^{[3][4][5][6][7]}

Contents 1 Mechanism/Symptoms 2 Mitigating the effects 3 Other effects 4 Other similar conditions 5 References 6 External links

[edit] Mechanism/Symptoms

Alcohol dehydrogenase (ADH) is responsible for conversion of primary alcohols to aldehydes; aldehydes are then converted to carboxylic acids by aldehyde dehydrogenase (ALDH). In the case of ethanol, the alcohol found in alcoholic beverages, ethanol is converted first into acetaldehyde and then into acetic acid. Acetaldehyde is the most toxic of these three compounds, and is both a possible carcinogen and a major cause of hangovers; ethanol's toxicity is lower, and acetic acid is relatively harmless.

The result is the accumulation of acetaldehyde. Approximately half of people of Asian descent are considered to be sensitive to alcohol due to this condition. ^[8] Flushing, after consuming one or two alcoholic beverages, includes a range of symptoms: nausea, headaches, light-headedness, an increased pulse, occasional extreme drowsiness, and occasional skin swelling and itchiness. These unpleasant side effects often prevent further drinking that may lead to further inebriation, but the symptoms can lead to mistaken assumption that the people affected are more easily inebriated than others.

[edit] Mitigating the effects

Much anecdotal evidence suggests that ingestions of low doses of heartburn medicine, containing ranitidine or famotidine (such as Zantac or Pepcid AC), may be able to relieve the body of the symptoms if taken an hour before drinking.^[9]

It is not known definitively why ranitidine and famotidine may, in some cases, but not all, help reduce the symptoms of the alcohol flush reaction.

One possible theory that may explain the effects of famotidine (and similar classed drugs) on the skin erythema or redness secondary to alcohol consumption is because the drugs are H2-antagonists or H2 antihistamines, which are used to treat peptic/gastric ulcers. In essence, if the "Asian flush" is an allergic reaction to the alcohol, then the mechanism of action of H2-antagonists can explain its effects on curtailing or decreasing the redness. However, H2-antagonists do not actually reduce blood concentrations of histamine, but rather works by reversing the effect of histamine on the H2 receptor, and so this theory is disputed.

Another theory, is that acetaldehyde causes the redness and vasodialation, and because the H2-antagonist class of medicine inhibits the ADH enzyme(the conversion from ethanol to acetaldehyde) both in the GI tract and in the liver^[10], the conversion happens at a much slower pace, reducing the effects acetaldehyde has on the drinker. The idea that acetaldehyde is the cause of the flush is also shown by the clinical use of Antabuse, which blocks the removal of acetaldehyde from the body via ALDH inhibition. The high acetaldehyde concentrations described share similarity to symptoms of the flush(flushing of the skin, accelerated heart rate, shortness of breath, throbbing headache, mental confusion and sight being hazy).

Although many people with this condition view it as a lifetime inconvenience, some people have suggested that they can condition their body to be more tolerant of alcohol with repeated, moderate drinking, perhaps increasing the concentration of ALDH2 to metabolize acetaldehyde. Unfortunately, acetaldehyde is a known carcinogen; recent research suggests that alcohol flush-afflicted individuals consuming alcohol continually may be at a higher risk for alcohol-related diseases, such as liver and esophageal cancers and digestive tract cancer.^[8]

Studies in rats have also shown that consumption of carbohydrates (glucose & fructose) significantly increase the metabolism of ethanol through a yet unknown pathway, and without affecting alcohol dehydrogenase activity.^[11]

[edit] Other effects

Individuals who experience the alcohol flushing reaction may be less prone to alcoholism. Antabuse, a drug sometimes given as treatment for alcoholism, works by inhibiting acetaldehyde dehydrogenase, causing a five to tenfold increase in the concentration of acetaldehyde in the body. The resulting irritating flushing reaction is intended to discourage alcoholics from drinking.^{[12] [13]}

Persons prone to the condition also have lower blood pressure, perhaps as a result of their much lower levels of drinking alcohol.^[14]

[edit] Other similar conditions

• Rosacea, also known as gin blossoms, is a chronic facial skin condition in which capillaries are excessively reactive, leading to redness from flushing or telangiectasia. Rosacea has been mistakenly attributed to alcoholism because of its similar appearance to the temporary flushing of the face that often accompanies the ingestion of alcohol.
• Degreaser's flush -- a flushing condition arising from consuming alcohol shortly before or during inhalation of trichloroethylene (TCE), an organic solvent with suspected carcinogenic properties.
• Carcinoid syndrome -- episodes of severe flushing precipitated by alcohol, stress and certain foods. May also be associated with diarrhea, wheezing and weight loss.
• Red Ear Syndrome, PMID 8797453, thought by many to be triggered by alcohol among other causes.

[edit] References

[edit] External links

• ClinicalTrials.gov NCT00661141 Phase IIa Study of Fomepizole for Acetaldehyde Toxicity After Ethanol Exposure in Subjects With Altered Ethanol Metabolism
• Asian Blush/Flush/Glow Community Forums
• Face turns red after drinking on the Go Ask Alice website, published January 24, 2003
• Wall TL, Peterson CM, Peterson KP, et al (1997). "Alcohol metabolism in Asian-American men with genetic polymorphisms of aldehyde dehydrogenase". Ann. Intern. Med. 127 (5): 376–9. PMID 9273829. http://www.annals.org/cgi/content/full/127/5/376. 
• Treatment for Asian Flush?
• Reducing the negative effects of alcohol by taking cysteine and vitamin C
• BBC News Article
• The Wonders of Zantac