GUIDE
Before switching formula, try slower-flow nipples and better burping. If gas persists, partially hydrolyzed formulas like Gentlease or Total Comfort are the evidence-based next step.
Almost every newborn is gassy. Their digestive system is brand new and still figuring things out. Most of the time, the formula isn't the problem — but sometimes a switch can genuinely help. Here's how to tell the difference.
Your baby's digestive system is roughly the size of their fist and has never processed food before. Gas is an inevitable byproduct of digestion, and for newborns, the whole system is still learning how to move things along efficiently.
Here is what is actually happening: newborn intestines have not yet developed the coordinated muscle contractions (peristalsis) needed to move gas through efficiently. The gut microbiome is still establishing itself. And babies swallow air — during feeds, during crying, sometimes just because. All of this means gas.
The AAP notes that most newborn gassiness peaks around 4-6 weeks and gradually improves by 3-4 months as the digestive system matures. This timeline holds regardless of what formula you use.
So before you assume the formula is the problem, consider: is this just normal newborn gas?
Switching formula should not be your first move. The techniques below solve the problem for many babies — and they are free.
Fast-flow nipples cause babies to gulp air along with milk. If your baby is coughing, sputtering, or milk is leaking from the corners of their mouth, the flow is too fast. Drop to a slower nipple size — even newborn flow nipples for young babies.
Hold baby in a more upright position (about 45 degrees), keep the bottle horizontal so milk just barely fills the nipple, and let baby pull milk in at their own pace. This reduces air intake dramatically. Most hospital lactation consultants teach this technique.
Don't wait until the bottle is finished. Burp after every 1-2 ounces for young babies. Try different positions: over the shoulder, sitting upright on your lap, or face-down on your forearm. Some babies burp easily in one position and not another.
Keep baby upright for 10-15 minutes after feeding. Gravity helps gas rise and escape before it gets trapped lower in the digestive tract. This is especially helpful for babies who spit up a lot.
Air bubbles in the bottle mean air bubbles in the baby. Anti-colic bottles (like Dr. Brown's) use a vent system to reduce air in the milk. Mixing formula by swirling instead of shaking also reduces bubbles.
Give these changes at least a week before evaluating. If you are tracking feeds and symptoms in an app like tinylog, note when you made the change so you can look back and see whether things actually improved or if you are just having a better day.
| Step | Formula Type | When to Try | What Changes | Time to Evaluate |
|---|---|---|---|---|
| Step 1: Standard Formula | Enfamil NeuroPro, Similac 360, any standard | Starting point for all formula-fed babies | Baseline — intact proteins, full lactose | 2-3 weeks |
| Step 2: Feeding Technique | Same formula, different approach | Baby is gassy but otherwise thriving | Slower nipple, paced feeding, better burping, upright position after feeds | 1 week |
| Step 3: Partially Hydrolyzed | Gentlease, Total Comfort, GentlePro | Gas persists after technique changes for 1-2 weeks | Pre-broken-down proteins, usually reduced lactose | 1-2 weeks |
| Step 4: Extensively Hydrolyzed | Nutramigen, Alimentum | Symptoms persist on gentle formula + signs of possible CMPA | Fully broken-down casein protein. Requires pediatrician guidance. | 2-4 weeks |
| Step 5: Amino Acid-Based | EleCare, PurAmino | No improvement on extensively hydrolyzed — rare | Free amino acids instead of any intact protein. Pediatrician-directed only. | 2-4 weeks |
"Gentle" formulas are not just standard formula with something added. They are structurally different in ways that matter for digestion.
Protein hydrolysis is the key change. Standard formula contains intact cow's milk proteins — large molecules that require significant digestive work to break down. Partially hydrolyzed formulas pre-break these proteins into smaller pieces using enzymes, similar to what your baby's stomach would do. Smaller protein fragments are easier and faster to digest, which means less fermentation in the gut and less gas.
Reduced lactose is the other common change. Most gentle formulas replace some or all of the lactose with corn syrup solids or maltodextrin. This is not because lactose is bad — it is the primary carbohydrate in breast milk and the ideal sugar for infants. But reducing lactose can help babies whose lactase enzyme production is still ramping up, which is a normal developmental process.
To be clear: this does not mean your baby is lactose intolerant. True congenital lactose intolerance is exceptionally rare in infants — fewer than 50 cases have been documented in medical literature worldwide. The AAP considers it virtually nonexistent in babies under 12 months. What your baby might have is transient developmental lactase insufficiency, meaning their enzyme production is still catching up. This resolves on its own.
| Formula | Protein Change | Carbohydrate Change | Other Changes | Approximate Cost |
|---|---|---|---|---|
| Enfamil Gentlease | Partially hydrolyzed nonfat milk and whey | Corn syrup solids (reduced lactose — 20% vs 80% in standard) | Includes 2'-FL HMO, DHA, MFGM | ~$1.15/oz |
| Similac Total Comfort | 100% partially hydrolyzed whey | Corn syrup solids (reduced lactose) | Includes 2'-FL HMO, DHA, lutein. No palm oil. | ~$1.20/oz |
| Enfamil Reguline | Partially hydrolyzed nonfat milk and whey | Corn syrup solids, polydextrose, galactooligosaccharides | Prebiotics specifically for stool consistency. For babies with both gas and constipation. | ~$1.15/oz |
| Gerber Good Start GentlePro | 100% partially hydrolyzed whey (comfort proteins) | Lactose, corn maltodextrin | 2'-FL HMO, DHA. Retains more lactose than other gentle formulas. | ~$1.10/oz |
| Store Brand Gentle (various) | Partially hydrolyzed nonfat milk and whey | Corn syrup solids (reduced lactose) | Varies by brand. Same FDA requirements. Significantly cheaper. | ~$0.65-0.75/oz |
Log feeds and note symptoms like gas, fussiness, or spit-up. When you switch formulas or try a new technique, you'll have a clear before-and-after picture instead of relying on memory.
Every formula brand has a "gentle" version, and they all claim to reduce fussiness and gas. Here is what they leave out:
Most gentle formulas are very similar. Enfamil Gentlease and its store-brand equivalents have nearly identical ingredient lists. The main difference is the label and the price. Store-brand gentle formulas cost 40-50% less and meet the same FDA requirements.
"Clinically proven to reduce fussiness in 24 hours" needs context. You will see this claim on Gentlease packaging. The study behind it was funded by Mead Johnson (Enfamil's parent company), measured parent-reported fussiness (subjective), and compared switching to Gentlease vs. staying on a standard formula. When you switch any formula, parents tend to pay more attention and use better feeding technique. Placebo effect is real and powerful, especially when you are sleep-deprived and desperate.
Gas drops may not do much. Simethicone drops (Mylicon, Little Remedies) break up gas bubbles in the stomach but do not prevent gas from forming. A randomized controlled trial published in Pediatrics (Metcalf et al., 1994) found simethicone no more effective than placebo for infant colic. They are safe, so there is no harm in trying — but don't expect a miracle.
Switching formulas too quickly creates its own problem. Every formula switch causes a 3-5 day adjustment period where stools change and fussiness may temporarily increase. If you switch every few days, you never give any formula a fair trial, and you add digestive disruption on top of whatever was already happening.
Normal gas is uncomfortable but manageable. If your baby has gas PLUS any of the red-flag symptoms above, talk to your pediatrician before switching formula on your own.
Talk to your pediatrician about your baby's gas if:
Bring your feeding log. Seriously. Your pediatrician will want to know how much your baby is eating, how often, what formula you are using, when the gas seems worst, and what you have already tried. That data turns a vague "my baby is gassy" into a productive conversation with a clear next step. If you are using tinylog or a similar tracker, share the data.
For more on hypoallergenic formulas, including when you need one and how they compare, see our hypoallergenic formula guide.
Most newborn gas is normal and temporary. It peaks around 4-6 weeks and improves by 3-4 months regardless of formula type. Start with feeding technique changes — slower nipple, paced feeding, better burping — before switching formula.
If gas persists, partially hydrolyzed formulas like Enfamil Gentlease or Similac Total Comfort are the evidence-based next step. Give any new formula at least 1-2 weeks. Don't escalate to extensively hydrolyzed formulas without pediatrician guidance — they are expensive, they taste different (babies sometimes resist the switch), and they are designed for a specific condition (CMPA) that most gassy babies do not have.
The "best" formula for your gassy baby is ultimately whichever one resolves the symptoms while keeping your baby well-fed and growing. For our full formula comparison, see our best baby formulas guide.
This guide is for informational purposes only and is not a substitute for professional medical advice. If you have concerns about your baby's gas, fussiness, or feeding tolerance, please consult your pediatrician.
