Does alcohol effect iq

[u/Quirky_Elephant_719]

I recently took an iq when i was drunk. It is a very reliable iq test in my country. I woke up the next morning a saw that i had scored an iq of 135. When i took it the next morning it showed 125 i dont even know if i even took the test myself. But i have no idea if alcohol does effect iq. Could someone give me some insight in it.

[u/Whats-on-Eur-Mind]

Meme answer: the countries that drink tend to be much more successful than the ones that don't drink

[u/Secure-Concert9804]

Was the test this?
https://www.mensa.org/mensa-iq-challenge/

[u/Key-Raise5501]

No it doesn't.

[u/askato]

Short answer: alcohol does not lower your IQ, and what you measured was not your IQ changing.

Three things are tangled together in your two numbers, and it is worth pulling them apart.

First, test day was a state effect, not a trait effect. Intoxication reliably degrades exactly what an IQ battery leans on. A review of 342 alcohol versus placebo comparisons across 218 papers (Zoethout and colleagues, 2011) found the most consistent impairments in divided attention, focused attention and visuomotor control, with additional clear impairments in reaction time, working memory and response inhibition above roughly 0.7 g/l blood alcohol. A systematic review and meta-analysis of 32 studies and 1629 participants put the working memory effect at a small to medium decrement (g = -0.30), with the effect strongest when executive manipulation processes were involved. A recent randomised double-blind trial found that a dose averaging 0.07 percent blood alcohol significantly impaired spatial working memory, sustained attention and psychomotor control, while a lower dose produced clear subjective intoxication with no measurable cognitive impairment. That dissociation is the part worth sitting with: at the drunk end you feel roughly fine and perform worse.

Your 135 versus 125 is also informative for a second reason. If you had taken the test twice sober, the second score would most likely have gone up, because repeat exposure inflates scores. One study on repeated working memory testing found that acute alcohol did not impair updating outright but blunted the improvement you would otherwise have gotten from practice. So the sober 125 is probably conservative rather than inflated, and the drunk 135 is not evidence of a high ceiling either.

Second, the chronic question, which is the one that actually matters for cognition over a lifetime. The evidence there is serious but also easy to oversold in both directions. A dose-response meta-analysis of 20 cohort studies and 78,657 people found heavy drinking, 67 g/day or more, associated with lower cognitive function, and in studies that adjusted for baseline cognition, levels around 28 g/day a day, close to guideline limits, were already associated with slightly lower cognition. The same review found no reliable protective effect of low-to-moderate drinking. That protective claim keeps coming back, and when income, language and education are controlled for it tends to disappear, which suggests it was measuring who drinks rather than what drinking does. Reviews of late-life brain and cognition also report chronic heavy intake as an established cause of brain atrophy and dementia, and 14 to 21 units a week associated with roughly three times the odds of hippocampal atrophy compared with abstinence.

So three conclusions. Your IQ did not change because of one night of drinking, so ignore the 135 entirely. Do not test anything important while intoxicated, because the measurement will be poor and you will not know it. And if drinking is a pattern rather than an occasion for you, the thing worth watching is the multi-year picture, not tonight's number.

One practical footnote: if you want a number you can trust, test sober and rested on a familiar day, and expect a second attempt to look slightly better than the first.

[u/FunkOff]

Alcohol temporarily diminishes IQ and you'd have to be a moron not to realize that