Does butter before bed help babies to sleep?

What the evidence says

There's no scientific study looking at giving babies butter before bed. The idea probably comes from folk beliefs that a 'heavier,' higher-fat food will keep a baby fuller and asleep longer, similar to the old practice of adding rice cereal to a bedtime bottle.

That cereal idea was actually tested in a randomized trial, and it made no real difference to how long babies slept through the night. More broadly, research in children shows that eating a lot of fatty food right before bed tends to be linked with worse sleep quality, not better, likely because it can be harder to digest.

Other studies on introducing solid foods earlier show mixed, mostly small effects on infant sleep, and none have isolated fat or butter as the ingredient responsible for any change. So while a full, satisfying feed before bed can help some babies settle, there's no evidence that butter specifically is the key ingredient, and it isn't a recommended or tested sleep strategy.

If you're looking for ways to help your baby sleep, consistent bedtime routines and appropriate feeding for age are better-supported approaches than adding butter to food or bottles.