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Skinny Baby – What To Do And When To Worry About Your Baby

Skinny Baby – What To Do And When To Worry About Your Baby

21st century society is obsessed with physical appearance and fitting in so it’s no wonder that any abnormality in a baby’s growth or weight gain would trigger alarms in parents, especially if they’re dealing with an overly skinny baby.

However, not every skinny baby is necessarily malnourished or sick.

There are some babies who are born genetically lean with a fast-acting metabolism whose body mass index won’t rise no matter how much you feed them.

It’s just the way nature works sometimes and some kids don’t get that chubby look when they’re really young, but that doesn’t mean they’re unhealthy.

However, that’s also where the risk lies.

How can you know if your baby is genetically lean or is skinny for some other reason if both conditions practically look the same?

Well, read on to find out what the difference between the two is as well as how to remedy the situation.

Do You Have A Skinny Baby?

young mother holding newborn baby on bed

There are plenty of reasons as to why a child might be a bit too thin around the waist.

The easiest way to determine the cause is by taking him to a doctor so they can check if his growth curve matches that of the official growth charts.

These growth charts were developed by the World Health Organization (WHO) for parents to be able to track, more reliably, whether they have a slightly chubby baby, a skinny one, or a little one whose growth is progressing as expected.

They’re so well documented that even the Center for Disease Control (CDC) itself recommends relying on them for a correct diagnosis.

The charts are used for newborns all the way up to 2 year olds.

They determine their statistics by taking your baby’s weight and his age (on a month old basis) into account, placing them each on an axis and figuring out where these points meet.

That point will show you the baby’s weight percentile which you can then use to check if it’s over or under the norm.

There are different charts for girls and boys since they have different values that are considered healthy given the difference in growth.

You should keep this in mind, especially if you have a boy and a girl.

Using the body mass index (BMI) to determine whether you have a healthy baby is not recommended for kids under 2.

How To Determine Whether Your Little One Is Underweight Or Not

mother holding her sleeping baby hand in bed

To figure out whether your baby boy or girl has a healthy weight, it’s best to visit a pediatrician for a check-up.

While there are online resources for the WHO charts, getting a check up at a pediatrician or your family doctor for your little guy or girl will do more than just determine the healthiness of your child’s weight.

You can also go in for a general physical to make sure everything is alright and check whether there are any underlying medical issues that you need to address.

There are several factors that determine a child’s weight during the first 2 years or so:

1. Genetics

As with every person, genetics will always play a role in growth, big or small.

Depending on the parents, a baby may turn out to be either a skinny baby or one of the more chunky babies.

This is something that’s out of the parents’ control as it’s mostly the mishmash of genes that combine and create a wonderful little human and these genes will determine the speed of his metabolism.

It might happen that even with regular breastfeeding or formula-feeding, your child just ends up processing the breast milk or formula too fast or too slow when compared to another child.

Not every baby is the same which is why every baby requires different feeding schedules.

Make sure to carefully study your little one’s eating habits and determine the right amount and frequency for your child.

It’s highly unlikely that you’ll get the right balance the first time around, but trial and error is a common part of parenting, so keep trying until you get it right. Of course, talk to your doctor about your options.

​If you don’t try to adjust and fix the diet early, depending on the case, the child might end up with a milder case of obesity or could end up severely underweight so make sure you don’t delay that doctor’s visit.

Genetics also plays a role in shifting the expected period when developmental milestones are supposed to hit, which can affect when your child swaps to solid foods or when his digestive system matures which can determine how much weight he puts on.

2. The difference between formula-fed and breastfed babies

young mother holding baby in arms and feeding with milk bottle

How you feed your baby might play a big part in whether your child is over or underweight.

Kids who breastfeed might end up being slightly underweight mostly due to the issues that may come with either an imbalance of foremilk and hindmilk, various issues with milk supply, or the mother’s diet.

There’s also the potential risk of infantile lactose intolerance that might complicate weight gain.

On the other hand, a baby that’s bottle fed with baby formula will have a consistent feeding pattern.

This might end up causing your little one to go over the estimated weight, partly from the consistent feeding pattern and partly from the ingredients in the formula itself.

This won’t necessarily cause a massive problem but might raise a few alarms if you’re not aware.

It can all be solved, just like the first issue, by either increasing or decreasing the frequency of your feeds or making your breast milk fattier, so you don’t have to give up on your preferred way of feeding your child.

3. Low birth weight

A child’s birth weight sets a precedent for what his first two years might be like in terms of weight in general.

So, if your child is born with a low birth weight when there were no other complications such as a premature delivery or something similar, he’ll usually remain as such for a good while.

While this might be quite commonplace, there are some instances where it might pose a problem and your doctor is best suited to diagnose that so you can help remedy the situation before worse complications can occur.

At some point, supplementing your baby’s food with vitamins to help him absorb nutrients might be necessary as some kids with low birth weight have a failure to thrive.

This is usually present in kids who were prematurely born and spent some time in the NICU.

A child carried to full term is less likely to have these issues, but the chance still exists, so always keep an eye on your little one’s weight gain.

How Do I Know That My Kid Is Healthy?

newborn baby with hands up sleeping in white bassinet

Looking out for signs of an underweight baby isn’t the only thing you should be on the lookout for.

Some babies are built to be lean while others are built to be more chunky, and that’s perfectly normal.

However, it can all be a bit confusing.

Here are a few things to keep a lookout for so you know that your child is growing up just fine and hitting those developmental milestones:

1. Your child has baby rolls

If you see that your child has those rolls of baby fat that make him look like a fluffy little loaf of bread, then you can rest assured that he definitely has enough weight and that he’s progressing in his development just fine.

However, don’t freak out if your baby doesn’t have baby rolls. This is okay, especially if your doctor says that your baby is developing well.

2. Regular wet poops

smiling mother changing diaper to her newborn baby in the bedroom

If your child’s bowel movements are fine and he has around half a dozen wet diapers per day, then you can rest assured that your child is getting enough food to sustain him (as long as it’s not full-blown diarrhea).

Anything substantially less or more than that is a good indicator that something might be wrong.

The same goes for seeing lots of dry poops as well as any changes in its color, consistency, or the presence of mucus. Black specks in the stool might be harmless, but if you notice them, it would be better to consult a health care professional.

If any of this is the case, steps might need to be taken to ensure your child remains healthy.

3. Your child is hitting the developmental milestones

There are a number of childhood leaps that happen during your child’s first two years of life that are a good way of tracking whether or not things are progressing smoothly.

For instance, if his emotional range is expanding, it’s a good sign that everything is going according to plan.

The same goes for the steady development of motor skills like gaining the ability to roll over or the evolution of his cognitive abilities.

These milestones should be reached during a certain period of time and if they aren’t, something might be off.

You should check in with your family doctor to make sure everything is okay.

Some of the clear-cut signs that something is wrong are:

• The baby’s bowel movements are late, dry or the baby is constipated often,

• Lack of appetite and sometimes a refusal to breastfeed or bottle-feed,

• Your child’s movements feel slow, like he’s dragging himself and lacking energy.

Other Causes Of Malnourishment And Growth Problems

cute baby sleeping in a bassinet with white frame covered with cozy blanket

Failure to thrive might sound like a rather serious condition, but it’s just a fancy way of saying the loss of appetite due to an underlying issue that’s preventing the child from gaining weight.

It is solved by supplementing the lost nutrients over a few weeks until the baby is back on track.

There are a few things that cause failure to thrive and sometimes they require special diets to deal with them or they might go away on their own.


Gastroesophageal reflux disease (GERD) is not uncommon in babies.

The condition disrupts their appetites and eating because it sends some of the stomach contents back up the esophagus.

This then causes an uncomfortable burning feeling (thanks to the stomach acid) which might even cause the baby to refuse food.

It’s caused by a weakened lower esophageal sphincter that can’t close properly due to a still underdeveloped digestive system.

Reflux usually goes away on its own around the child’s first birthday.

Some parents who are formula-feeding switch to a special acid reflux formula.

In severe cases, surgery might be necessary.

2. Celiac disease

newborn baby crying on the bed next to mother

Another, more debilitating issue can be Celiac disease.

Recently, it has gained more attention in the medical field as it’s becoming a more prevalent issue.

It’s an intolerance to gluten, something that’s a common ingredient in a lot of food you’ll find on the market and is part of the daily diet of almost every person.

However, having a gluten allergy or intolerance isn’t the end of the world.

The market has adapted to include gluten-free options so even those suffering from Celiac disease can live a healthy and full life with little to no issue.

It’s just a matter of making up the lost ground from before the issue was discovered as it’s known to cause a level of malnutrition and failure to thrive.

3. Any form of severe health condition or heart condition

Speaking of debilitating issues, there’s nothing worse than medical conditions with no currently known cures that stay with our kids for their entire lives.

Cerebral palsy, diabetes, various forms of heart disease, cystic fibrosis, and the like are known to have an adverse effect on a child’s diet and overall appetite, ultimately leading to issues with consuming food.

As there are no known cures for such conditions, you can only help your child manage the symptoms to live a healthier life.

Your child might require a specific diet or treatment to maintain a healthy weight.

Helping A Skinny Baby Gain Weight

beautiful mother feeding her baby with milk bottle

As this can be a rather common issue, the solution to some of the less dangerous reasons for a baby who’s a bit underweight can be rather simple. These are some of the ones that your doctor might suggest:

1. Increase the frequency of your feeds

This is the most common solution.

If the baby isn’t gaining enough weight, then maybe he isn’t getting enough food.

So, the solution is to feed the baby more often if possible to supplement the missing nutrients.

For moms who breastfeed their kids often, but can’t keep up with the necessary demand as there’s simply not enough supply, a few doses of baby formula in between nursing can be a great solution.

The same goes for formula-fed babies, though they’ll exclusively have to rely on formula in case of potential lactose intolerance or other allergies that correlate with breast milk.

2. More variety helps

mother feeding her newborn baby with milk bottle on the bed

Once your child is at least a year old and has swapped over to solids, the problem might be in the food that you’re offering.

Your baby might not like how the food tastes, or even its texture. As a result, your baby might gain weight slowly.

The best solution here that doctors will often suggest is to introduce some more variety into your baby’s diet.

That way you’ll have a more robust selection and can figure out which foods your baby likes most.

Alternatively, they might suggest simply getting more nutritious foods in smaller packages, that way kids get tricked into eating more even though it looks like less.

Things like active and engaging feeding time help too, like the good ol’ choo choo train and the airplane tactic.

Always Remember That Your Doctor Is Your Best Friend

young mother holding her baby girl while doctor examining her

Dealing with a chubby or skinny baby can potentially be a sign of a really serious underlying health issue.

But many serious health conditions are preventable if you get the right medical help in time.

This is why it’s important to always rely on your child’s pediatrician when it comes to these issues as they’re the first people who are likely to know the answer to the problem.

They can perform a live diagnosis for your baby boy or girl to determine the exact cause of your child’s poor weight gain and how it can be treated.

Just because advice exists on the internet, doesn’t mean that it’s going to be the one that works out for your child.

Most of the advice you find online is of a general nature, so it’s not going to provide a solution to every single case.

Your little one might be an exception to the rule.

That’s why doctors are there to properly assess your child and prescribe a treatment.

Treat anything you read on the internet as more of a guideline rather than the absolute truth.

In Conclusion

a newborn baby sleeping peacefully on bed in white sheets

The causes of a skinny baby are quite varied in their severity.

More often than not, the causes are quite harmless and can be resolved through a little bit of guidance.

However, all kids are unique in their own right and what works for your child might not work for another and vice versa.

If this is the case, then you can talk to your child’s pediatrician and develop a diet that’s tailor-made for your child.

They’ll be able to stabilize your little one’s nutrition and get the weight right back on track.

If your little one is reaching all of his child leaps in good time, then you have little to worry about.

As long as your baby is growing continuously and developing further, then that means that he’s well-fed.

Until next time, mammas.

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