As the summer approaches we start drinking more. A cold pint in a beer garden on a sun is a pleasure, but what's the science behind world most popular legal drug? Which grandma's advices are actually true, and which are completely, utterly ridiculous? Lets' s look at some myths, stereotypes and research behind the substance, that kills around 100,000 people globally every year (computed by Wolfram Alpha).
1. Alcohol is a poison.
TRUE. And naturally humans produce a defence against it - an enzyme called 'alcohol dehydrogenase' (AD). This enzyme is a way your body fights back booze and gets you sober. The enzyme grabs hydrogene from ethanol molecule and makes it non-toxic acetaldehyde. Well, it's non-toxic, but a high cumulation of it will eventually cause dehydration and hangover.
2. Asians bodies don't produce alcohol dehydrogenase.
FALSE. It's a genetic variation that caused some of them produce less than in Caucasians. Variation was large enough to affect 1/3 of Asian drinker's population. Their great-great-grandparents simply didn't get so wasted Friday night as in Caucasian culture.
3. Women get easier drunk than man.
PARTIALLY TRUE. There are many factors, but generally AD enzyme mentioned previously is much more effective in man than women (70-80% greater activity in man than woman). However there is a tradeoff - AD enzyme activity drops much quicker for man than for women with age - so later in life those differences disappear.
4. Better eat before you get pished.
TRUE, but not because food 'soaks' the alcohol. When your stomach is full, it closes a small valve that leads to your small intestine (called 'pyloric sphincter'), so your stomach will have time to process the food before it gets to high-absorption intestine. If you drink on empty stomach - your pyloric sphincter is wide open and leading straight to 200 square meters of absorption surface in the small intestine that will happily suck the alcohol into your blood stream very fast and get you knocked.
5. If I drink one-half-pint-per-hour, I should be ok to drive us home.
WRONG. Your alcohol absorbtion and elimination is a curve, not a straight function.
6. Drunk bums live longer.
TRUE, to some extend ;-) Surprised? Well, in the recent study published in Alcohol: Clinical and Experimental Research journal, Holahan et al. (2010) followed 1824 people over a total of 20 years, as they aged between 55 and 65. Of those who totally abstained 69% died. From 'light drinkers' - 64% died. Among those who drunk 'moderately' - 41% died. Even heavy drinkers did better than abstinents and light drinkers - 61% of them passed away during the study.
As the summer hits, this topic will get covered more, with other drugs too, so stay tuned.
As the summer hits, this topic will get covered more, with other drugs too, so stay tuned.
Like! :)
ReplyDeleteI think 1. is pretty cool in that it implies that people with strong heads for alcohol suffer worse hangovers, which only seems fair (if you're a pansy like me.)
I'm not very impressed with 6. because it seems very difficult to control for things like lifestyle and character. I'll risk a guess that many of those who abstained were doing so for religious reasons, and religion often introduces non-random, harmful behavioral patterns, like avoiding certain types of food, or denying yourself medical help. Also, the participants in all the groups seem to have been self-selected.
Cheers:) About 6 - they took the whole bunch of covariates under consideration, like socio-economic status, health problems, depressive symptoms, etc. They got pretty solid stats - I can send you a paper if you are interested in details. Also, the population sample is quite large. Variables like religiosity could be a confound, but they have quite large sample in their hands. Participants were contacted by them, they weren't self-selected.
ReplyDeleteWell, I suppose they knew what they were doing :) Did they figure out why did the people who didn't drink die more often? If it wasn't because of health, quality of food, nor psychological effects, what was it?
ReplyDelete@Pies: They are actually very sceptical about their own results - they spend half discussion outlining problems with their study ;-) But this is what they say regarding explanation of results:
ReplyDelete"The apparent health-protective effects of moderate alcohol consumption compared to abstention may be related to reductions in cardiovascular illness (Corrao et al., 2004). Plausible mechanisms include the role of alcohol in increasing high-density lipoprotein cholesterol, fibrinolysis, endothelial function, and antioxidant effects and in reducing plasma viscosity, fibrinogen concentration, platelet aggregation, and inflammation (Kloner and Rexkall, 2007; Rehm et al., 2003)"
"In contrast, the adverse health effects of high compared to moderate alcohol consumption appear primarily because of noncardiovascular illnesses. Alcohol misuse is associated with several cancers (oral cavity, esophagus, and larynx), cirrhosis of the liver, chronic pancreatitis, and hypertension, as well as with injuries (Corrao et al., 2004). Importantly, any health-protective effects of alcohol appear to be limited to regular moderate drinking. Heavy episodic drinking even when average consumption remains moderate is associated with increased cardiovascular risk (Rehm et al., 2003;Room et al., 2005).
I guess that just because something seems counterintuitive doesn't make it false :) It's like with the Chernobyl power plant incident that actually _lowered_ deaths from cancer in the people affected by the supposedly harmful radiation.
ReplyDeletehttp://zdrowie.onet.pl/profilaktyka/czarnobyl-nie-zniszczyl-cial-lecz-glowy,1,4246365,artykul.html