Enfamil AR vs Enfamil A2 (2026): Which Formula Is Better?

Same Brand, Different Problems

Enfamil AR (~$30/12.9 oz) and Enfamil A2 (~$35/19.5 oz) are both made by Mead Johnson (Reckitt), but they address completely different infant feeding challenges. Enfamil AR uses rice starch to thicken formula in the stomach and reduce spit-up — it's built for reflux. Enfamil A2 uses exclusively A2 beta-casein protein from specially selected cows, targeting babies who experience gas, fussiness, or digestive discomfort that may be related to A1 protein sensitivity.

The critical distinction: AR fixes a mechanical problem (formula coming back up), while A2 addresses a digestive problem (formula causing discomfort going down). Identifying which issue your baby has is the key to choosing correctly.

Enfamil AR: The Anti-Reflux Formula

Enfamil AR contains rice starch that stays liquid in the bottle but thickens when exposed to stomach acid. This added weight helps keep formula in the stomach rather than traveling back up the esophagus. Clinical studies show it reduces spit-up episodes by approximately 50%.

• Price: ~$30 for 12.9 oz powder
• Active ingredient: Rice starch — thickens in stomach acid to reduce reflux
• Protein: Intact nonfat milk + whey protein concentrate (contains both A1 and A2 proteins)
• Carbs: Lactose + rice starch
• Fats: Palm olein, soy, coconut, high-oleic sunflower oils with DHA/ARA
• Target symptom: Frequent spit-up, diagnosed GER
• Bottle prep: Standard nipple; may need vigorous shaking to dissolve fully

Enfamil A2: The Gentle Digestion Formula

Enfamil A2 uses milk exclusively from cows that naturally produce only A2 beta-casein protein. Standard cow's milk contains a mix of A1 and A2 proteins. Some research suggests the A1 protein produces a peptide called BCM-7 during digestion, which may contribute to digestive discomfort, gas, and bloating in sensitive individuals. By eliminating A1, Enfamil A2 aims to provide gentler digestion while keeping intact (non-hydrolyzed) milk protein.

• Price: ~$35 for 19.5 oz powder
• Active feature: A2-only beta-casein protein — eliminates A1 protein that may cause digestive discomfort
• Protein: Intact A2 cow's milk protein (both whey and casein, but only A2 variant)
• Carbs: Lactose (no rice starch or corn syrup solids)
• Fats: Palm olein, soy, coconut, high-oleic sunflower oils with DHA/ARA
• Target symptom: Gas, fussiness, bloating, digestive discomfort not caused by full milk protein allergy
• Bottle prep: Mixes like a standard formula — straightforward preparation

Head-to-Head Ingredient Comparison

Since both are Enfamil products, they share the same base vitamin/mineral fortification and DHA/ARA levels. The differences are in the functional ingredients:

• Protein type: AR uses standard cow's milk protein (A1 + A2 mix). A2 uses exclusively A2 protein. Neither is hydrolyzed — both use intact protein, so neither is appropriate for confirmed cow's milk protein allergy (CMPA).
• Thickening agent: AR includes rice starch. A2 has no thickener — it won't reduce spit-up.
• Carbohydrate source: Both use lactose as the primary carb. AR adds rice starch on top. A2 uses lactose only.
• Fat blend: Nearly identical vegetable oil blends in both formulas.
• Prebiotics: Neither includes significant prebiotic fiber (unlike some other Enfamil lines).
• Calorie density: Both provide standard 20 kcal/fl oz when prepared as directed.

Price and Availability

• Enfamil AR: ~$30 for 12.9 oz (~$2.33/oz powder). Available at most US retailers. Eligible for Enfamil coupons/rewards and WIC in some states.
• Enfamil A2: ~$35 for 19.5 oz (~$1.79/oz powder). Available at most US retailers. Slightly less ubiquitous than AR but easily found online.
• Per-ounce value: A2 is actually cheaper per ounce of powder. But if your baby has reflux, the per-ounce cost is irrelevant — you need the formula that addresses the symptom.

Stool and Digestive Differences

• Enfamil AR stools: Tend to be firmer due to rice starch. Some babies experience constipation. Stools may appear greenish. This is an expected trade-off of the thickening mechanism.
• Enfamil A2 stools: Parents commonly report softer, more comfortable stools compared to standard A1/A2 formulas. Less gas and bloating are frequently noted as well.
• If AR causes constipation: Talk to your pediatrician — they may suggest tummy massage techniques, bicycle legs, or (for babies 6+ months) small amounts of water or prune juice.

Decision Guide: Which Enfamil Does Your Baby Need?

• Choose Enfamil AR if: Your baby spits up frequently and in large amounts, your pediatrician has identified reflux (GER), or spit-up is affecting weight gain or causing visible discomfort during/after feeds
• Choose Enfamil A2 if: Your baby is gassy, fussy, or bloated without significant spit-up; you suspect A1 protein sensitivity; or your baby has digestive discomfort on standard formula but doesn't have a confirmed milk protein allergy
• If your baby has BOTH reflux AND gas/fussiness: Consult your pediatrician. The root cause matters — sometimes reflux itself causes gas (from swallowing air during spit-up episodes), and solving reflux with AR may resolve the fussiness too. Alternatively, an underlying milk protein sensitivity could be causing both symptoms, requiring a different approach entirely (like Nutramigen).
• If symptoms are mild: Try the standard Enfamil NeuroPro first. If spit-up is the primary issue, switch to AR. If gas/fussiness is the primary issue, try A2.

Common Mistakes Parents Make

• Using AR for gas: Rice starch thickens formula to prevent spit-up. It does nothing for gas, bloating, or digestive discomfort — and may actually worsen constipation.
• Using A2 for reflux: A2 protein is easier to digest for some babies, but easier digestion ≠ less spit-up. Reflux is a mechanical issue that requires a thickening agent.
• Switching too quickly: Give each formula at least 5-7 days before evaluating. Some digestive adjustment is normal when switching any formula.
• Self-diagnosing: Both reflux and digestive sensitivity overlap with symptoms of cow's milk protein allergy (CMPA). If AR doesn't help reflux or A2 doesn't help fussiness, consult your pediatrician — the issue may require a hydrolyzed or amino acid-based formula.

The Bottom Line

Enfamil AR and Enfamil A2 are both specialty formulas from the same manufacturer, but they target completely different symptoms. AR's rice starch physically reduces spit-up — it's for reflux babies. A2's exclusive A2 protein reduces digestive discomfort — it's for gassy, fussy babies. Matching the formula to your baby's actual symptom is the entire decision. If your baby spits up: AR. If your baby has gas and fussiness without significant spit-up: A2. If your baby has both: that's a pediatrician conversation, because the root cause determines the right approach.