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Formula feeding basics

Formula is straightforward once two things are locked in: mix it exactly as the label says, and respect the clock on a prepared bottle. Everything else — brand, temperature, bottle shape — is preference.

Mixing it right

  • Wash hands and use a clean, dry bottle. Sterilise bottles for babies under three months, premature babies, or any baby with a weakened immune system.
  • Water first, then powder. Adding powder first changes the final volume and the concentration.
  • Use the scoop that came in the tin, levelled — never packed, never heaped, never a scoop from a different brand.
  • Never dilute to stretch a tin and never over-concentrate to "fill" a baby. Both are genuinely dangerous.
  • Swirl or roll rather than shaking hard to cut down on air bubbles.

How long it keeps

StateRoom temperatureRefrigerator
Freshly mixed, untouched2 hours24 hours
Bottle the baby has drunk from1 hour, then discardDo not refrigerate
Ready-to-feed, opened container2 hours48 hours
Opened powder container1 month in a cool, dry cupboardDo not refrigerate

Prepared formula is never frozen. When in doubt about a bottle's age, tip it out — it is cheaper than a stomach bug.

Warming safely

Stand the bottle in warm water or use a bottle warmer. Never microwave — hot spots scald a mouth even when the bottle feels fine.

Combining with breast milk

Mix formula with water first, then add already-prepared breast milk. Track the split by volume so intake records stay accurate.

Switching brands

Any standard cow's-milk formula meets the same nutrition rules. Stools may change for a few days; only change type on your pediatrician's advice.

Night feeds without the fumbling

  • Pre-measure powder into a dispenser and pre-fill bottles with water.
  • Many babies happily take room-temperature formula — worth trying before you commit to warming at 3am.
  • Make a fresh bottle rather than reheating a partly drunk one.

What to write down

Time, volume, and whether the bottle was formula, breast milk, or a blend. That is enough to answer every question at the next appointment and to spot a genuine change in appetite. For amounts by age see how much milk a baby needs, and for pacing the bottle itself see paced bottle feeding.

Log formula, breast milk or a blend

Nestli splits blended bottles by volume so daily totals stay honest.

Start tracking now!