so when i first started drinking ACV it made me SUPER tired at first. id drink just a swig and lots of water and id be out for a nap 45 minutes later i guess its normal at first while your body processes all the junk out of your body? but i later found out that you should never drink it straight out of a bottle because its bad for the enamel of your teeth. always dilute it. and drink the dilution out of a straw and avoid the teeth as much as possible still! my husband isnt so careful but i like my teeth and id rather not put them at risk. but he drinks it every night still!