The condiment should always be diluted whether that be in water or in a tea because it is a vinegar and could cause harm to the tooth enamel as it is very acidic.
Healthline suggests that drinking the drink before bed doesn’t have any more benefits than it does if you were to drink it throughout the day.
It says: “Some evidence suggests that drinking small amounts of apple cider vinegar before bed may help lower morning blood sugar levels in people with type 2 diabetes, though more research is needed before it can be recommended as an effective natural treatment.”
Drinking apple cider vinegar at least 30 minutes before bed may lower your risk of indigestion or acid reflux after laying down.
source: express.co.uk