Baby Reflux Explained: What’s Normal, What’s Not, and What You Can Do

By Dr. Alli Chisholm, PT, DPT

Disclaimer: This post may contain affiliate links. If you purchase through my links, I may earn a small commission at no extra cost to you. I only recommend products I personally use and love with my own family and clients.

Baby reflux is one of the most common questions I get from new parents — and one of the biggest sources of stress. There’s so much information (and misinformation) online that it’s no wonder parents end up spiraling, wondering if something is “wrong” with their baby or if they’re missing something serious.

My goal here — as always — is to bring you the truth about baby reflux and spit-up, grounded in research, developmental science, and real-world experience working with hundreds of babies and parents through The Moving Peanut.

And first things first: let’s address the myth I hear all the time that honestly makes me cringe every time I see it floating around Instagram or in Facebook mom groups —

“Baby reflux is common but never normal.”

This is simply not true.

Trust me — I get it. My first baby spit up a lot. We were constantly covered in milk, doing endless laundry, and constantly googling “why does my baby spit up so much?”. And while we did have a few feeding concerns to address, she was never actually bothered by the spit-up.

Our pediatrician lovingly called her a “happy spitter,” which honestly felt a little triggering at the time — because how could anything that looked so dramatic possibly be normal?

If you’re in that season where your laundry pile seems never-ending, I personally loved using Dreft Stage 1: Newborn Laundry Detergent — it’s gentle, hypoallergenic, and actually gets the milk smell out without irritating baby skin.

Our first covered in spit up before bed (in our favorite SwaddleMe Pod, of course).

But I understand that term now. She was experiencing normal, physiological spit-up for her age. And while yes, it was messy (and I carried burp cloths everywhere we went), there wasn’t an underlying cause to worry about.

So let’s take a deep breath together and unpack what’s actually happening when babies spit up — what’s normal, what’s not, and how to support your baby in a way that’s backed by both science and sanity.

Spit-Up vs. Reflux: What’s the Difference?

Most babies spit up. Some do it occasionally, others after almost every feeding. The medical term for this is gastroesophageal reflux (GER) — and it’s a normal, physiological process that happens because your baby’s digestive system is still developing.

But when reflux starts causing pain, discomfort, poor weight gain, or feeding challenges, that’s when it becomes gastroesophageal reflux disease (GERD).

Here’s the key difference:

As one study notes, “Physiological gastroesophageal reflux (GER) must be distinguished from gastroesophageal reflux disease (GERD)... if the infant is growing well and not distressed, this is a benign, normal condition and should not be treated with anti-reflux medication.” (Leung & Hon, 2019)

Why Reflux Happens in Babies

Here’s what’s really behind most cases of spit-up and reflux:

1. An Immature Digestive System

Babies are born with a developing lower esophageal sphincter (LES) — the little muscle that keeps stomach contents from flowing back up. Because it’s not fully mature, milk can easily come back up the esophagus.

2. Tiny Stomach Capacity

At birth, a newborn’s stomach holds about 20 mL — less than an ounce. Yet a single letdown reflex can release 35–40 mL of milk (Bergman, 2013). That mismatch often leads to overflow.

3. Frequent Feedings

Newborns eat frequently — sometimes 8–12 times a day — which is exactly what they’re supposed to do for optimal growth (Kent et al., 2007). But frequent feeds mean more opportunities for spit-up.

4. Lying Flat

Babies spend a lot of time lying down, which naturally makes reflux more likely compared to an upright adult.

5. Overfeeding or Fast Let-Down

When too much milk comes in too quickly — whether from bottle flow or a strong letdown/oversupply — it can overwhelm your baby’s stomach and trigger reflux.

6. Food Sensitivities or Allergies

Cow’s milk protein intolerance or other sensitivities can irritate your baby’s gut and mimic reflux symptoms.

7. Underlying Medical Causes (Less Common)

Conditions like pyloric stenosis, eosinophilic esophagitis, or true GERD are much rarer but important to rule out if symptoms are severe.

Common Myths About Baby Reflux

Let’s address a few more myths that make new parents worry unnecessarily:

• Myth: “You must burp your baby after every feed or they’ll spit up.”
  → Truth: Although the sample size was small, one study found no significant difference in spit-up rates between burped and non-burped infants (Kaur et al., 2015).

• Myth: “Propping the baby up in their crib helps reflux.”
  → Truth: Elevating or side-lying a baby during sleep does not reduce reflux episodes and actually increases the risk of SIDS (Moon, 2016). Always keep sleep flat and on the back, unless otherwise directly by a medical professional working specifically with you and your child.

• Myth: “All reflux requires medication.”
  → Truth: Most reflux is physiological and improves on its own. Medications should only be used for diagnosed GERD under medical supervision.

When to Worry: Signs Reflux Might Be GERD

While spit-up is normal, these are signs to call your provider for further evaluation:

• Poor or inconsistent weight gain

• Frequent projectile vomiting

• Blood in spit-up or stool

• Arching or crying during or after feeds

• Chronic coughing, choking, or gagging

• Difficulty feeding or refusing feeds

• Signs of dehydration (fewer wet diapers, sunken soft spot)

If these sound familiar, it’s worth digging deeper into what’s going on — including feeding patterns, possible oversupply, allergies, and latch mechanics.

How to Help Your Baby (Without Panic or Overwhelm)

1. Feed Responsively

Watch your baby’s cues instead of sticking to rigid schedules. Overfeeding (especially when baby uses feeding to soothe instead of hunger) can worsen reflux.

2. Upright Positioning After Feeds

Hold your baby upright for 20–30 minutes after feeding. Avoid tight waistbands (including tightly-fastened diapers), car seats, or baby swings right after a feed.

Our own spit-uppy baby being held upright in a baby wrap post-feed.

3. Burp Strategically (Not Obsessively)

Burping can help some babies — but it’s not a magic fix. Try pausing mid-feed to allow a short break for air release if your baby seems fussy.

4. Adjust Flow or Feeding Technique

If bottle-feeding, use a slow-flow nipple and paced feeding technique to reduce air intake. If breastfeeding, evaluate for oversupply or forceful let-down.

👉 To see a list of my recommended bottles as a lactation-informed infant physical therapist, check out my Holiday Gift Guide for Babies 0–6 Months: Parent-Approved Developmental Toys & Essentials.

5. Address Possible Sensitivities

If you suspect dairy intolerance, consider a short maternal dairy elimination trial or switch to a hypoallergenic formula under guidance.

6. Reserve Medication for GERD

Medications like famotidine or omeprazole are for cases of confirmed GERD causing pain or growth issues — not for mild spit-up. (Lightdale & Gremse, 2013)

7. Consider Probiotics

Certain strains, like Lactobacillus reuteri, may help reduce reflux symptoms in some babies by supporting gut health (Indrio et al., 2014).

💡 Parent tip: If your baby’s reflux means constant outfit changes (for both of you!), I recommend washing everything in a fragrance-free, baby-safe detergent like Dreft Stage 1: Newborn. It’s been my go-to for years — gentle enough for sensitive skin, but strong enough to handle those milk-soaked sleepers.

The Tongue Tie Connection: What the Research Actually Says

You might’ve heard that tongue ties cause reflux — and while this theory circulates widely online, the research doesn’t support a direct cause-and-effect relationship.

Tongue ties can absolutely affect feeding mechanics, sometimes leading to more air intake or inefficient milk transfer, which can contribute to reflux-like symptoms. However, most studies show there’s no strong evidence that tongue ties directly cause reflux (Walsh et al., 2017; Douglas & Geddes, 2018).

One study did report that babies who underwent frenotomy (tongue-tie release) showed a sustained improvement in reflux-like symptoms six months after the procedure (Slagter et al., 2021). However — and this is important — that study did not include a control group (a group of babies with tongue ties who did not have a release). Without that comparison, it’s difficult to know whether the improvement was due to the procedure itself or simply the natural maturation of the baby’s digestive and anatomical systems that occurs during that stage of development.

In short: while tongue ties may indirectly worsen reflux symptoms through feeding challenges, they’re not a root cause of reflux. If you suspect a tongue tie, the most important step is a comprehensive feeding assessment, not a rush to surgery. A skilled provider can help you understand whether your baby’s symptoms are truly related to latch, oversupply, or other underlying causes before making any decisions.

Bottom Line: Reflux Isn’t Always a Problem

Me as a tired, new mom-of-two, covered in spit up (while I was embarrassed by this photo initially, I love it now, seeing how happy I am with my beautiful newborn, despite how tired - and stinky - I was).

Here’s what I want you to know: most of the time, baby reflux is a normal part of infancy — messy, yes, but not dangerous.

I wish I could go back and tell my first-time mom self that. Because while I spent so much time trying to fix what wasn’t actually broken, what my baby really needed most was comfort, connection, and for me to trust that her body was doing exactly what it needed to do.

Your baby’s digestive system is learning, growing, and adapting, and the vast majority of babies outgrow reflux by 12–18 months.

But if your gut says something more is going on — or if your baby seems in pain, fussy, or is struggling with feeds — trust that instinct. There are always ways to uncover the why and make feeding more comfortable for everyone involved.

Parent Essentials for “Reflux Season”

These are a few things that made life easier when the spit-up felt endless:

• Dreft Stage 1: Newborn Laundry Detergent – gentle on baby skin, tough on milk stains

• My favorite bottles for calmer, more controlled bottle-feeds are listed in this guide

• Muslin burp cloths you’ll actually want stacked everywhere

• Ergobaby Newborn Carrier – perfect for keeping your baby upright after feeds while freeing up your hands (and giving you a little breathing room!)

Disclaimer: This post contains affiliate links, which means I may earn a small commission at no extra cost to you. I only share products I truly love and recommend to the families I work with.

Need Support?

If your baby is struggling with reflux, feeding challenges, or tension that’s making feeding uncomfortable, you don’t have to figure it out alone.

I specialize in virtual pediatric physical therapy and wellness coaching for parents like you — helping you uncover the root causes behind symptoms like reflux, tightness, or head preference so you can confidently support your baby’s comfort and development from home.

👉 Book your virtual assessment here to get personalized guidance for your baby — or grab my free guide, How to Help Your Baby Love Tummy Time (Even If They Cry Every Time) to start supporting healthy digestion and motor development right now.

References

• Bergman, N. (2013). The capacity of the newborn stomach.

• Douglas, P. S., & Geddes, D. T. (2018). Practice-based interpretation of the evidence on tongue-tie, breastfeeding, and frenotomy. Frontiers in Pediatrics, 6, 252. https://doi.org/10.3389/fped.2018.00252

• Indrio, F., et al. (2014). Probiotic supplementation in the first 6 months of life reduces gastrointestinal disorders in children: A randomized controlled trial. JAMA Pediatrics, 168(3), 228–233. https://doi.org/10.1001/jamapediatrics.2013.4367

• Kaur, G., Singh, G., & Gupta, M. (2015). Burping versus no burping in infants: Randomized controlled trial. Journal of Child Health Care, 19(4), 474–482. https://doi.org/10.1177/1367493514523943

• Kent, J. C., Mitoulas, L. R., Cregan, M. D., Ramsay, D. T., Doherty, D. A., & Hartmann, P. E. (2007). Volume and frequency of breastfeedings and fat content of breast milk throughout the day. Pediatrics, 117(3), e387–e395. https://doi.org/10.1542/peds.2005-1417

• Leung, A. K. C., & Hon, K. L. (2019). Gastroesophageal reflux in children: An updated review. World Journal of Pediatrics, 15(3), 240–248. https://doi.org/10.1007/s12519-019-00229-6
  Lightdale, J. R., & Gremse, D. A. (2013). Gastroesophageal reflux: Management guidance for the pediatrician. Pediatrics, 131(5), e1684–e1695. https://doi.org/10.1542/peds.2013-0421

• Moon, R. Y. (2016). SIDS and other sleep-related infant deaths: Updated 2016 recommendations for a safe infant sleeping environment. Pediatrics, 138(5), e20162938. https://doi.org/10.1542/peds.2016-2938

• Rosen, R., et al. (2018). Pediatric gastroesophageal reflux clinical practice guidelines: Joint recommendations of NASPGHAN and ESPGHAN. Journal of Pediatric Gastroenterology and Nutrition, 66(3), 516–554. https://doi.org/10.1097/MPG.0000000000001889

• Slagter, K. W., Raghoebar, G. M., Hamming, I., Meijer, J., & Vissink, A. (2021). Effect of frenotomy on breastfeeding and reflux: Results from the BRIEF prospective longitudinal cohort study. Clinical Oral Investigations, 25(6), 3431–3439. https://doi.org/10.1007/s00784-020-03665-7

• Walsh, J., Links, A., Boss, E., & Tunkel, D. (2017). Ankyloglossia and lingual frenotomy: National trends in inpatient diagnosis and management in the United States, 1997–2012. Otolaryngology–Head and Neck Surgery, 156(4), 735–740. https://doi.org/10.1177/0194599816689648