Depending on age, different foods can help your baby gain weight. Babies under 6 months should be given breastmilk or formula, while older children can have foods such as oatmeal, avocado, and eggs.

baby eating oatmealShare on Pinterest
d3sign/Getty Images

If you’re worried that your baby might weigh too little, keep in mind that newborns normally lose 7 to 8% (and up to 10%) of their birth weight in their first few days of life, which they regain by about the end of their second week.

Until they reach the 6-month mark, infants should gain about 1 poundTrusted Source (0.45 kg) or more each month. They should weigh about tripleTrusted Source their birth weight around the end of their first year.

These numbers are averages, and a healthy baby may have different weight gain numbers depending on their birth weight, rate of linear growth, and other factors. You can ask your baby’s pediatrician about weight gain at any time, such as at their well-baby exam.

If your baby is 6 months or older and your healthcare practitioner have ruled out medical reasons for your baby’s slow weight gain, such as heart or digestive issues, consider feeding them calorie-dense whole foods. These may encourageTrusted Source healthy weight gain.

Breastfed newborns will feed 8–12 timesTrusted Source in a 24-hour day for the first few weeks. After this, once appropriate weight gain is established, some babies may feed less frequently.

Be sure to let your infant fully empty your breast. This is recommended because hindmilk, which comes out at the end of a feeding, may have more fatTrusted Source than foremilk, which comes out at the beginning.

Additionally, avoid wearing tight-fitting bras or tops. These types of clothes can prevent your milk from flowing freely.

Your doctor may ask about any latching issues and investigate any underlying medical issues that may affect your baby’s nutrient absorption or metabolism at this age.

Speak with a pediatrician for guidance if you’re considering whether to supplement breastfeeding with formula or are wondering which formula to choose. These choices are complicated and depend on many personal factors, and a doctor can help you make informed decisions.

You may also consider talking with a lactation consultant.

Most babies will start to show readiness to eat solid foods around the 6-month mark. Speak with your healthcare professional about when to start your baby on complementary solid foods.

Try to introduce new foods one at a time. This way, if your child has an allergic reaction, you have a better sense of what might have caused it.

Avocado

Avocado can be a good transitional food for babies starting on solids.

The healthy fats in avocadoTrusted Source, combined with its relatively mild taste, make this a great food for when you’re trying to get your baby to gain weight. Be sure to mash it up or puree it before giving it to your baby.

Oatmeal

To make oatmeal suitable for your baby, blend plain oats cooked in water, adding water as needed to achieve a soupy texture. To make it heartier, cook and thin out the oatmeal with formula or breastmilk instead.

You can gradually thicken it as your baby gets more comfortable.

Oatmeal contains beta glucan, which is a form of soluble dietary fiber. This may help strengthen your baby’s immune system. Oatmeal may also help reduce inflammation and constipation.

Oatmeal is fairly neutral in taste, which makes it easy to combine with other hearty, healthy foods. For instance, you can spoon in puréed fruit and cinnamon for more flavor.

Avoid honey

Though you may add honey to your own oatmeal, never feed it to a baby under 1 year old. Doing so can put them at risk of botulism and pose a choking hazard.

Peanut butter

Peanut butter packs protein and fatsTrusted Source — both of which can encourage weight gain in your baby.

However, whole peanuts should not be given, as they are a choking hazard.

The latest evidence supports feeding infants as young as 6 months foods that commonly cause allergies. This includes peanut butter. Research suggests this approach may help prevent allergies from developing.

It’s important to watch for signs of allergies, including:

If one or more of these symptoms occur, seek medical help immediately.

Never feed your baby peanut butter straight from the jar, as doing so may pose a choking hazard. The best way to feed them natural peanut butter, or any other type of nut butter, is to blend it with:

If you’ve already introduced dairy, yogurt is also an option.

If your child is at a higher riskTrusted Source of allergies or has had eczema, speak with a healthcare professional before feeding them any nut butters or higher-risk foods. They may advise waiting until they’re older and then want to supervise this in their office or suggest an allergy test first.

Common food allergies

In addition to peanuts, the most common food allergies includeTrusted Source:

Eggs

Scrambled eggs can serve as a complementary food for babies. Eggs contain docosahexaenoic acid (DHA), a type of omega-3 fatty acid that is essential for proper brain development in early childhood.

Fish

You don’t have to hold off until the 9-month mark to introduce fish, but it might be easier for babies to handle the texture at this age.

Fish is rich in protein and healthy fats. Try to seek out low mercury fish, such as:

  • salmon
  • herring
  • trout

These and other fish also contain DHA.

You can pair fish with a full-fat yogurt dip for added nutrients.

When babies hit their 12-month milestone, you may find that they’re eating less. This is because their growth rate slows. Most toddlers will only put on about 5 poundsTrusted Source between their first and second birthday.

Of course, they are still growing and still need lots of nourishment. They are just not growing quite as rapidly as they were in those first 12 months of life.

Don’t be worried if your champion eater suddenly slows down or plateaus at this phase. If they still have the energy to play and seem alert, they’re probably doing just fine.

Olive or avocado oils

Your toddler should get a fair amount of healthy fats. In fact, 30–40% of your toddler’s calories should come from fats.

They need roughly 1,000-1400 caloriesTrusted Source each day at this age. This translates to about 30–50 grams of fat per day.

If your toddler needs a bit more support, consider adding a splash of olive oil or avocado oil to their food, about 1/4–1/2 tablespoon (4–7 mL) to start.

You can add it into a bowl of soup or hummus or sop some whole grain bread into it.

Take care not to feed your baby too much oil, as doing so could cause gastric upset or diarrhea.

Should you be worried about your child’s weight?

Unless a healthcare professional has identified an issue with your baby’s weight, you probably don’t need to worry.

Keep in mind that babies born prematurely and those with special health needs may not track along with general growth charts.

That said, it is a good idea to voice any concerns you may have with your child’s healthcare professional. Take note of what you observe that troubles you, in as much detail as possible. For example, you could record the times, dates, amounts, and types of food your child has eaten.

If your baby seems lethargic, is refusing to feed, or isn’t meeting developmental milestones, you should make an appointment to speak with a healthcare professional, such as a pediatrician. In addition to a medical evaluation, they may refer you to another specialist, lactation consultant, occupational therapist, or dietitian.

There are many nourishing foods to help support your baby’s growth, including eggs, avocados, and peanut butter.

If your baby is under 6 months, try to provide enough opportunities for them to breastfeed or drink enough formula according to their hunger cues.

If you notice that your child is refusing to eat, seems lethargic, or is not meeting developmental milestones, talk to your child’s doctor. They can help you find a solution or refer you to another medical professional who can.