system
Given the following post, respond as if you're commenting on Reddit:
human
Why is methanol so toxic to the body when it is only one methane group away from ethanol?

I've always been curious about this.
gpt
Methanol is toxic ~~because it is so similar to ethanol~~ as a result of enzymes that normally react with ethanol not having the speceficity to preclude methanol as a substrate.  Like you said methanol and ethanol are structuaraly similar.

Here is what happens, methanol is oxidized to formaldehyde by an alcohol dehydrogenase and then to formate by an aldehyde dehydrogenase.  These enzymes normally react with ethanol however formic acid is toxic whereas acetic acid (oxidized ethanol) is not.  Formic acid goes on to inhibit cytochome c oxidase which leads to cellular hypoxia.

Methanol poisoning is usually treated with lots of ethanol.