The major health organizations — including the American Academy of Pediatrics (AAP), American Medical Association (AMA), the American Dietetic Association (ADA), and the World Health Organization (WHO) — agree that breast milk is the ideal form of nutrition for babies (especially during the first 6 months). However, it's your choice to decide what's best for you and your baby.

Whether you've decided to formula feed your baby from the start, are supplementing your breast milk with formula, or are switching from breast milk to formula, you're bound to have questions. Here are answers to some common inquiries about formula feeding.

How can I tell when my baby is hungry?

It's generally recommended that babies be fed whenever they seem hungry, which is called demand feeding (or feeding on demand).

And if your baby is very young, or having problems gaining weight, you shouldn’t go too long without feeding, even if it means waking your baby. In this case, talk to your doctor about how often your baby should be fed.

Despite what some new parents might think, crying is a late sign of hunger. You should try to feed before your baby gets so hungry that he or she gets really upset and becomes difficult to calm down. It's also important, however, to realize that every time your baby cries it is not necessarily because of hunger. Sometimes babies just need to be cuddled or changed. Or they could be overstimulated, bored, or too hot or too cold.

If your baby is crying only an hour after a good feeding, there may be something else causing the distress.

Signs that babies are hungry include:

• moving their heads from side to side
• opening their mouths
• sticking out their tongues
• placing their hands, fingers, and fists to their mouths
• puckering their lips as if to suck
• nuzzling again their mothers' breasts
• showing the rooting reflex (when a baby moves its mouth in the direction of something that's stroking or touching its cheek)

Watch your little one's cues so that you're feeding when your baby is showing signs of hunger, which is usually every 2-3 hours during the newborn period. As your baby gets a little bigger and can take bigger feedings, this stretches out to every 3-4 hours.

How often should I make my baby's bottles?

Some parents opt to make a bottle just before each feeding, but many others choose to pre-make and refrigerate enough to use for the day. If you know your baby eats every 3-4 hours, for instance, you can make six to eight bottles to last you all day.

Mix your baby's formula in 2- or 3-ounce (60- or 90-milliliter) servings for the first few weeks and gradually increase the amount as you become familiar with your baby's eating patterns and appetite. Remember to refrigerate it immediately after mixing.

If your baby is staying with a caregiver for a long period of time, you may want to prepare just one or two bottles and leave instructions and supplies (bottles, nipples, formula, and water, if necessary) so the caregiver can prepare bottles as needed and not waste any formula. After all, you'll need to throw away any mixed formula after 24 hours.

Is my baby eating enough?

Babies grow at different rates, and at times you may wonder whether your baby is getting enough nutrients to develop properly. Here's a general look at how much your baby may be eating at different stages:

• On average, a newborn consumes about 1.5-3 ounces (45-90 milliliters) every 2-3 hours. This amount increases as your baby grows and is able to take more at each feeding.
• At about 2 months, your baby may be taking 4-5 ounces (120-150 milliliters) at each feeding and the feedings may be every 3-4 hours.
• At 4 months, your baby may be taking 4-6 ounces (120-180 milliliters), depending on the frequency of feedings and his or her size.
• By 6 months, your baby's formula intake can be between 24-32 ounces (720-950 milliliters). This also depends on whether you've introduced any baby food.

Your newborn's diapers are another good indicator of when your baby is getting plenty to eat. You'll probably be changing at least six wet and four dirty (soiled or "poopy") diapers each day at first.

Newborns' stools (or poop) are thick and tarry in the beginning and then become more yellow or green as they get older. Formula-fed babies often have firmer, less seedy stools than breast-fed babies.

Wet diapers should have clear or very pale urine. If you see orange crystals in a wet diaper, contact your baby's doctor — these can be a sign of inadequate fluid intake or dehydration.

Other possible signs of underfeeding include:

• not gaining enough weight
• seeming unsatisfied, even after a complete feeding

To help determine whether your baby is eating enough, follow the schedule of regular well-child checkups so that your little one can be weighed and measured. If you're concerned or notice any signs that your baby isn't getting enough nutrition, call your doctor.

Why does my baby seem hungrier than usual?

As babies gain weight, they should begin to eat more at each feeding and go longer between feedings. Still, there may be times when your little one seems hungrier than usual.

Your baby may be going through a period of rapid growth (called a growth spurt). These can happen at any time, but in the early months growth spurts often occur at around:

• 7-14 days old
• between 3-6 weeks
• 4 months
• 6 months

During these times and whenever your baby seems especially hungry, follow his or her hunger cues and continue to feed on demand, increasing the amount of formula you give as needed.

Reviewed by: Joseph DiSanto, MD, and Karin Y. DiSanto, IBCLC
Date reviewed: January 2012