Episode 76: Managing Underweight Children

Episode 76: Managing Underweight Children

In this episode of The Easy Feed Podcast, I’m diving into a topic that so many parents quietly worry about — children who are underweight or struggling to gain weight. Whether it’s a baby not feeding well, a toddler who’s suddenly lost interest in food, or a teenager skipping meals, understanding the “why” behind poor weight gain is key.

Drawing on more than 25 years of experience as a paediatric dietitian, I’ll take you through the medical, nutritional, and behavioural factors that can affect growth, and what you can do about them. From gut health to sensory issues and neurodivergence, we’ll unpack the signs to look out for, when to seek help, and how to support your child’s nutrition in a way that feels calm and achievable.

Links:
https://nourishwithkarina.com/feedingbabies
https://nourishwithkarina.com/membership

Highlights:

Introduciton (00:00.096)
Tracking Your Child’s Growth: Weight, Percentiles, and Understanding Poor Weight Gain (02:20.494)
Understanding Poor Weight Gain in Children: Causes, Feeding Challenges, and Growth Monitoring (04:36.49)
Why Some Children Struggle to Gain Weight: Allergies, Nutrient Deficiencies, Sensory Challenges & Medical Causes (06:53.622)
Understanding Poor Appetite and Weight Gain in Children: Medication, Anxiety, and Eating Challenges (09:07.276)
Maximising Nutrition for Children on Medication or With Neurodivergence: Strategies for Healthy Growth (11:27.478)
Maximising Nutrients and Gut Health for Healthy Growth in Children (13:41.336)
Gut Health, Nutrition, and Early Signs of Restrictive Eating in Children and Teens (16:01.09)
Understanding Underweight in Children and Teens: Causes, Nutrients, and Early Warning Signs (18:20.756)
Small Changes, Big Impact: Supporting Children’s Growth, Appetite, and Gut Health (20:34.572)

Show notes

READ TRANSCRIPT

Show Notes

Highlights

1. Understanding growth patterns
How to read growth charts correctly and know when to be concerned — and when not to.

2. Common causes of poor weight gain
From feeding issues in babies to food sensitivities, intolerances, and gut health problems in older children.

3. Supporting neurodivergent children
Practical ways to boost intake for children with ADHD or ASD, especially when appetite is reduced by medication.

4. Building healthy relationships with food
Spotting early signs of restrictive eating in teens and creating a positive food environment at home.

5. Making every bite count
Simple, evidence-based tips to increase calories and nutrients without mealtime stress.

Show Notes
Learn more about consultations

https://nourishwithkarina.com/nutrition-consultation

Contact: hello@nourishwithkarina.com
Instagram: @nourishwithkarina

Introduciton (00:00.096)
You're listening to the Easy Feed Podcast, episode number 76, Managing Underweight Children. Hi there, I'm Karina Savage and with over 20 years experience feeding children, including my own, I've learnt all the secrets that busy mums need to get their children eating better and actually enjoying healthy foods. So a huge welcome to the Easy Feed Podcast.

Welcome back to another episode. hope you're well. Today I wanted to record an episode, which I haven't done before. It's all about children who are underweight, struggling to gain weight for whatever reason, because this is a common issue that I see in my clinic online. And it's something that I've managed for my 25 years of my career, whether it's been neonates, babies who are struggling to gain weight properly.

Or it's toddlers and children who aren't absorbing and gaining weight properly, or it's teenagers who come with their own set of reasons as to why they aren't eating properly or they might be underweight. And it can be medical and it can also be restrictive. So I want to dive into all of that today, just to give you some context and understanding of the different underlying causes of why children might be underweight. And then some tips on I guess, what to do and...

how to manage when you are concerned about your child who might be underweight. So let's dive into it. So first of all, I want to talk about the fact that when children go from being babies to toddlers, the rate of weight gain and growth does slow down and their appetite can consequently change. And sometimes at this point, parents can get really worried about the fact that their child's just not eating as much as they used to.

But that's because the rate of weight gain. So if you look at the growth charts, that angle of how quickly they're gaining weight, it does level off a little bit. I mean, not a lot because they're obviously still growing, but it does definitely slow down. And that can therefore mean that they don't eat as much or don't appear to be as hungry. And that can sometimes worry parents. But what I do in my consults is I always get data. So weight.

Tracking Your Child’s Growth: Weight, Percentiles, and Understanding Poor Weight Gain (02:20.494)
height or length, depending on whether they're standing yet or not, and plotting those so that we have a history and I can see where they've come from, where they're at now. And I look at the pattern, I look at the growth pattern with their weight, with their height, I look at the percentiles and that helps to give you guidance on where the child's at and whether they actually are underweight or not.

BMI body mass index is another indicator and there are pediatric BMI charts that we can also use to assess whether a child is underweight or not. And I use all of that data in my consults to help guide parents accordingly and tell them, whether they really should be worried about their weight or not. And not that I want parents to be worried, but sometimes we do need to make it a real focus. Look, I've been referred patients by doctors who

have told them that their child is very underweight. And then when I get all the data points and we plot them out, we realize that actually they are tracking their own curve and they are actually okay. It's just that A, you've got to use the right growth charts and B, you have to be plotting them correctly so that you can really identify where they're at on the growth chart and whether or not they are actually tracking or whether their weight is flatlining or plateauing or dropping off percentiles.

Because that's when you do need to start to focus a little more on weight if they are crossing those percentiles. Okay. So now let's talk about some underlying causes of poor weight gain in children. And we'll start with babies. So with neonates, sometimes they are still establishing feeding and sometimes they need to be nasogastricly fed. Sometimes they're, and that's when you get a tube put down their nose because they still haven't, they're still too young to feed.

properly. Sometimes their gut is still too immature to be able to properly absorb nutrients effectively. So they may need specific formula to help them gain weight. So this is the kind of thing that I use to help patients with, I should say in a children's hospital where I spent the first 12 years of my career. Another cause of poor weight gain in babies is poor latch when they may not be able to latch properly or they're gulping a lot of air and they're very uncomfortable.

Understanding Poor Weight Gain in Children: Causes, Feeding Challenges, and Growth Monitoring (04:36.49)
It might be that they've got an allergy or an intolerance and therefore not able to feed effectively or not absorb properly. So there's a number of reasons why babies may not feed well and therefore not gain as much weight. It's very normal, I must say though, with newborns to lose some weight to start within that first week whilst they're establishing breastfeeding. And then they do recover that weight gain. And that can sometimes be a time when parents are really worried about the weight gain, but if you're being

advised by healthcare professionals in a hospital, they will tell you that they should tell you that that is absolutely normal. And it's all part of establishing that healthy feeding routine, that breastfeeding routine or the bottle feeding routine if you can't breastfeed, but it's normal. However, if that continues on, then it becomes a concern and then you need to get some help. But look in babies and toddlers teething will also impact a baby or child's willingness to eat or want to eat.

If their mouth is really sore, then they're not going to want to eat as much food and that can really knock off their appetite and sometimes their overall intake. So you may see a bit of a dip in their weight during those periods because they're just not interested in eating because it hurts them. And it's at those times that you may need to adapt the types of foods and the textures that you're giving them so that they are still able to eat effectively if they have got a sore mouth. Okay, moving into toddlers and children.

There are many reasons why a child may not eat well or may be underweight, but sensory food sensitivities can absolutely play a role. And if parents aren't in tune with managing those sensory preferences or those sensory challenges, then that can impact a child's intake and therefore their overall calorie intake and day in, day out, that can make a difference to their overall weight gain and growth.

gut intolerances, so lactose intolerance, fructose intolerance, sorbitol intolerance. So they're the kind of carbohydrate malabsorption issues that I see in children. They can also impact weight gain because if you're not digesting and absorbing the nutrients properly in the bowel and you're pooing too much of it out, then they're not able to get the calories from those carbohydrates. So that can impact weight gain as well. Sometimes children.

Why Some Children Struggle to Gain Weight: Allergies, Nutrient Deficiencies, Sensory Challenges & Medical Causes (06:53.622)
have allergies or intolerances to foods that make their tummies really sore. So they self-select to avoid those foods because they know it doesn't agree with them. And then that can also impact their total intake. Children who are constipated may also lose their appetite and not want to eat as much because they're full of poo. There's less room for food. It's not passing through properly. It can also affect their gut microbiome.

So kids who are constipated may also have issues with appetite and sometimes weight gain. mean, not all the time, but it can be a factor. Nutrient deficiency is another factor which will impact appetite and therefore can impact how much they eat. So nutrients, especially zinc and iron can impact appetite. It can really knock off a child's appetite, which means they don't want to eat as much. They don't put as much food in their mouth. They don't get as many calories. They don't gain weight as well.

They can be underweight. So it's important to be mindful of that in a child who is really leaning towards the white diet, doesn't eat much in the way of meat or protein foods that are richer in iron and zinc and that can impact their appetite. So just be mindful of that, especially if your child may have dark circles under their eyes. You those nutrient deficiencies can impact appetite. Well, one of the main medical causes for children who continue to

be underweight despite trying everything is undiagnosed celiac disease. Now look, it's only, you know, just over 1 % of the population in Australia. I do see a lot of children diagnosed with celiac. mean, that's, guess, part of my job, but it's important just to rule that out. If you've got a child who has ongoing poor weight gain, perhaps you've got a history of gut issues in the family.

autoimmune conditions, perhaps they have constipation or low iron. It is important to just get a screen for celiac just to rule that out. If there's ongoing poor weight gain. Back to the sensory side of things, neurodivergent children can absolutely have poor weight gain if they are struggling to eat enough because of perhaps food sensory issues. It might be medication as well that they're on. see plenty of children that are on.

Understanding Poor Appetite and Weight Gain in Children: Medication, Anxiety, and Eating Challenges (09:07.276)
medication for their ASD or their ADHD and it can really impact their appetite during the day. So these children may eat breakfast, but then may not eat again until late afternoon or dinner because they just don't have the appetite and that can really impact their overall calorie intake and therefore weight gain. So we need to be really strategic in that situation with how we feed them and what we feed them. Other factors that will influence a child's appetite is anxiety at the dinner table.

And sometimes this can play out with fussy eaters if there's a lot of pressure and stress at the dinner table. Sometimes children have anxiety for other reasons. And if they're anxious at meal times, this can really heighten their fight or flight response. And they may be further away from trying new foods or wanting to eat foods at dinner time because they are so anxious. And finally, children who are a bit older, who become more body conscious may develop body image issues.

They may start to really focus on being healthy and sometimes that focus can go a little too far and sometimes it evolves into restrictive eating or disordered eating. And I've certainly seen the whole spectrum there. I've worked with the worst of the worst and that, you know, the, nasty eating disorder and with children in hospital.

It's not fun and I really work hard when I do see patients online or in clinic to support these children, really get back on track and develop a healthy relationship with food that they can carry with them for life because restrictive eating can definitely impact overall nutrition intake and weight gain and therefore growth and development. You don't tend to see this as much in children under 10, it's more, you know, the teenage group.

that you see this presenting in and, there's obviously a concern and it needs to be managed appropriately with the right health professionals involved. I just want to elaborate a little more on those children who are on stimulant medication for ADHD like Ritalin, Concerta or Vyvanse. You may notice that they really reduce their intake over the school day and it is absolutely normal.

Maximising Nutrition for Children on Medication or With Neurodivergence: Strategies for Healthy Growth (11:27.478)
But if your child is already on the lean side, then it is really important that you start to address trying to maximise their intake at other parts of the day, whether it's front loading them at breakfast time and then loading them up again in the afternoon, evening, when they get home. It's really important to be strategic with.

Not only the types of foods, but the amounts of food and really trying to get them to eat as much as possible during those times when their appetite is a little higher, because medication can definitely influence their overall intake. And it's important to try to ensure that they are meeting all their nutrient needs as well as their total calorie needs. And sometimes supplements are important and required in neurodivergent children.

And that's through no fault of the parent. It's just situation. So if you do have a neurodivergent child and you are worried about their weight, please reach out to me and we can book an online consultation with all of my sessions. Using my provider number, we have private health rebates available or Medicare or NDIS rebates available too. So there's plenty of opportunities there and it's always better to have a professional look at your child, look at the whole situation holistically. look at weight, height.

blood results, food diary, assess nutrient intake, potential nutrient deficiencies, and then guide you accordingly. According to their sensory preferences, we talk about meal times, we talk about them holistically so that they have a really robust plan for how to manage them moving forward. It's going to tick their calorie intake, their protein intake, their nutrient intake, their sensory preferences. We talk about extra nutritional supplements that may be beneficial to neurodivergent children.

Because in a child who is underway and neurodivergent, there's a lot that nutrition can really impact their concentration, their focus, their growth and development. So I love helping parents who can then help their children because with a bit of extra nutrition, they can really thrive. At the end of the day, with any child who's underway, for whatever reason, we can't force food down their throat or we don't want to force food down their throat.

Maximising Nutrients and Gut Health for Healthy Growth in Children (13:41.336)
So it's about being very intentional and strategic with our approach so that we are still achieving the end goal without creating a drama for the child. We're doing it without them even realizing. We do need to make every bite count and it's not only about quantity, it's about quality. And that's where I come in to give you all of the tips to maximise every nutrient and every calorie so that we are getting everything in that your child needs. And we can't forget about...

gut health either, because it's probably not talked about as much. talk a lot about, you know, gut health being important for immune health, but gut health will also impact how we gain weight and how we metabolize food. So you can have two people that eat exactly the same food, exactly the same diet. I hate that word, but that's the name for it, I guess. And they will.

metabolize that food differently and gain weight differently based on their gut microbiome and how their gut microbiome metabolizes that food. So we digest and absorb food differently based on our gut microbes. Our hunger and fullness hormones are also directly impacted by our gut microbiome. And so people can have a very different

response with their hunger and fullness hormones based on their gut microbiome. And those that have a poorer gut microbiome, meaning there's a dysbiosis, so there's more bad bugs than good bugs, those people can have a poorer response in terms of hunger and fullness and it can therefore impact how much they eat. And sometimes in

Adults too, it can also mean that they overeat. So when a child's gut is healthy and balanced, these hormones stay in sync and then the hunger and fullness signals work much better. And how do we maximise gut health? Well, I've talked about this in other episodes, but fibre is the number one way that you're going to support your child's gut health. This is assuming that there's no allergies or inflammation that's already happening because that needs to be addressed first.

Gut Health, Nutrition, and Early Signs of Restrictive Eating in Children and Teens (16:01.09)
But fiber helps feed those gut microbes, the good gut microbes so that we have more of those good gut microbes and they are in good populations and there is a good diversity of these good, healthy microbes. So the gut is in a good balance and it's in a happy place. And when it is in a happy place, then everything's going to work better. There's going to be much healthier messages that go to the brain. So we're going to have better focus, mood, concentration, behavior.

We're also going to better digest and absorb nutrients and metabolize food in a better way so that we are healthier. Okay. I just want to finish off by talking a little bit more about teens and restrictive teens, because it's certainly an area that I've worked with in the past. I have a lot of experience with all different stages of eating disorders. And as a parent, I think it's really important just to be mindful of

early warning signs for children who do become restricted. And I think it's important that children understand that, you know, there's healthy foods and everyday foods and sometimes foods. But if you find that your child starts to become really hyper-focused on healthy foods, how much they're eating, or start to talk about carbs as being bad or fats as being bad or really eyeballing you as you're cooking dinner and telling you that, you know,

You shouldn't be adding so much oil or, you know, they're becoming really obsessed with food. Often they will actually still love to cook food and cook food for everybody else all day long, but they won't necessarily eat it themselves. If you're starting to see these early warning signs of, you know, hyper focus on food, then just be aware of it because it's really important that

We teach our teenagers how to have that healthy relationship with food if they haven't already developed it. Or sometimes they have developed it and then they sort of get thrown off on a tangent. might be peers at school. It might be something someone said. It might be that they've seen someone else eat a certain way or they've seen something online or social media, which is a nightmare in terms of body image and all of that. So it's, who knows where sometimes this, you know, initial seed

Understanding Underweight in Children and Teens: Causes, Nutrients, and Early Warning Signs (18:20.756)
of information comes from, but something can just trigger something in their mind. And all of a sudden they start weighing themselves, start staring at themselves in the mirror and they start becoming really hyper-focused on everything that goes into their mouth, planning their food, weighing their food, measuring their food. Just be really mindful of these warning signs because they are all warning signs that you need to book an appointment with someone like me.

to chat about it, to chat about how you can help your child to get back on track with just loving food and loving life really, because the more focus they get on the food and the more weight that they lose, the more vicious the cycle becomes. And then it can snowball out of control into an eating disorder. And so that's not something that we want, but it can definitely happen the more underweight they get. So.

I didn't want this podcast episode to be all about this, but I just wanted to mention that because it is something that I do see it is definitely out there and it's just important to be mindful of. And it happens to boys and girls. Okay. I'll wrap it up now. In summary, there's many reasons why children might be underweight and why their appetite may be affected. And whether it's a neonate, a baby, a child, or a teenager is really important to be

mindful of why they might be underweight. And once we can better understand why they're underweight, then we can put an action plan together that specifically addresses their underlying root cause of why they're underweight. And then we can really start to see some changes happen. Is not only making sure that their overall calorie intake is adequate, making sure their protein intake is adequate and their nutrients, their vitamins and minerals. So that includes fiber for gut health.

And that way, if we're all the nutrient boxes, then we're giving your child the best possible future. And really that's all you can do. So I recommend if you are concerned, seeing your doctor, seeing your pediatrician, reaching out to me, you can also find out more information on my website, nourishwithkarina.com, head to the consultation page and we can chat more about how I can help your child.

Small Changes, Big Impact: Supporting Children’s Growth, Appetite, and Gut Health (20:34.572)
Because often all we need to do is tweak a few things or tweak things across the day. And over the days and the weeks and the months, that really adds up to a huge change and a huge difference to your child. And don't forget about their gut health because that will also play a role. And I'm happy to help out there too. So I'll leave it there, but if you've loved this episode and you enjoy listening to me, then please leave me a review so that we can get this podcast out to more families. Reach out to me on Instagram.

send me an email hello at nourishwithkarina.com. I always love chatting and I will chat to you again next time. Bye for now.