GUIDE
ByHeart vs. Similac
ByHeart focuses on protein innovation and includes lactoferrin. Similac leads with 2'-FL HMO and palm-free fat. ByHeart costs roughly 2x Similac. Both are FDA-compliant.
ByHeart is one of the most expensive and most talked-about new formula brands. Similac 360 Total Care is America's bestseller. This guide breaks down whether ByHeart's premium ingredients justify a price that is double Similac's.
The Honest Starting Point
ByHeart and Similac 360 Total Care represent two very different approaches to infant formula. ByHeart is a venture-backed startup that bets on protein innovation and bioactive additions like lactoferrin. Similac is backed by Abbott Laboratories, one of the largest healthcare companies in the world, with decades of market dominance and the broadest distribution network of any formula brand.
Both are FDA-compliant. Both are nutritionally complete. The $100–125 monthly cost difference is the central question: does ByHeart's formulation philosophy produce meaningfully different outcomes for your baby?
The honest answer: we do not know yet. ByHeart's ingredients are thoughtfully chosen and scientifically interesting, but the evidence that they produce measurably better outcomes in healthy, full-term babies compared to Similac is not established. If the premium fits your budget, ByHeart is a well-made formula. If it does not, Similac (or a store brand) will nourish your baby just as well.
For feeding amounts by age, see our baby feeding chart.
| Feature | ByHeart | Similac 360 Total Care | What It Means |
|---|---|---|---|
| Manufacturer | ByHeart (founded 2019) | Abbott Laboratories (est. 1888) | Startup vs. one of the largest healthcare companies in the world |
| Protein source | Organic grass-fed whole milk protein (not separated) | Nonfat milk, whey protein concentrate | ByHeart keeps protein intact. Similac separates and recombines. |
| Fat source | Patented blend: organic high oleic sunflower, coconut, soy oils | High oleic safflower, soy, coconut oils (no palm olein) | Neither uses palm olein. Different proprietary blends. |
| Carbohydrate source | Organic lactose | Lactose | Both use lactose. No corn syrup solids in either. |
| Signature ingredients | Lactoferrin, whole protein, patented fat blend | 2'-FL HMO (human milk oligosaccharide) | Different bioactive strategies. Both target breast milk components. |
| DHA source | Algal oil | Algal oil (Schizochytrium sp.) | Both use algal DHA. |
| FDA approved | Yes | Yes | Both meet all FDA requirements under 21 CFR 107 |
| Price per oz (powder) | ~$2.20–$2.60/oz prepared | ~$1.10–$1.30/oz prepared | ByHeart costs roughly 2x Similac per ounce |
| Available at | byheart.com, limited retail | Everywhere — grocery, pharmacy, online | Similac is available at every major retailer. ByHeart is primarily online. |
The Ingredient Differences That Actually Matter
Both formulas avoid palm olein and corn syrup solids. The differences are in protein approach and bioactive additions.
Protein: whole vs. separated
ByHeart uses whole protein from organic grass-fed milk. Similac separates milk into skim and whey and recombines them. ByHeart argues their approach is closer to breast milk and may be gentler on digestion. The clinical evidence for this specific claim in term infants is limited.
Lactoferrin vs. HMO: different bioactive bets
ByHeart includes bovine lactoferrin, an immune-supporting protein found in breast milk. Research on lactoferrin supplementation is promising, particularly in preterm infants. Similac includes 2'-FL HMO, a prebiotic oligosaccharide that supports gut health. Both are real breast milk components with some evidence of benefit, but neither has been definitively proven to produce different outcomes when added to formula for healthy term babies.
These are different bets on which breast milk component matters most to replicate. Neither brand is wrong — they are prioritizing different aspects of a complex biological fluid.
Fat blends
Both avoid palm olein — a shared advantage. ByHeart has a patented fat blend; Similac uses high oleic safflower, soy, and coconut oils. The practical impact on your baby is likely minimal.
What the Marketing Doesn't Tell You
ByHeart markets itself as the formula that "finally gets it right" — implying that all previous formulas got it wrong. In reality, Similac and other conventional formulas have successfully nourished billions of babies. ByHeart's innovations are incremental improvements, not a fundamental breakthrough.
ByHeart conducted its own clinical trial, which showed growth equivalence to breast milk. This is the baseline expectation for all formula, not a unique achievement. Every FDA-compliant formula supports adequate growth.
Similac's 360 Total Care branding implies completeness — "total care" suggests nothing else is needed. This is marketing language for a standard infant formula with one added bioactive (HMO).
The $100–125 monthly gap between these formulas — and the $160–210 gap between ByHeart and store brands — is significant for most families. There is no evidence that spending more on formula produces a healthier baby. If you can comfortably afford ByHeart, it is a thoughtful product. If the cost creates financial stress, that stress is worse for your family than any ingredient difference between formulas.
| Product | Typical Price | Cost Per Oz (Prepared) | Monthly Estimate |
|---|---|---|---|
| ByHeart Whole Nutrition (powder, 22 oz) | $46–$54 | ~$2.40/oz prepared | ~$250–$300/month |
| Similac 360 Total Care (powder, 20.6 oz) | $33–$38 | ~$1.20/oz prepared | ~$150–$175/month |
| Store brand (for reference) | $16–$23 | ~$0.70–$0.85/oz prepared | ~$90–$120/month |
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Taste, Mixing, and Practical Differences
Taste: ByHeart has a slightly creamier taste. Similac is milder. Babies may prefer one over the other.
Mixing: Both dissolve well. ByHeart can be slightly thicker. A formula pitcher works for either.
Availability: Similac is available everywhere. ByHeart is primarily direct-to-consumer. This is a significant practical difference — when you run out at 2 AM, Similac is at the nearest pharmacy. ByHeart requires advance planning.
Supply reliability: Similac's massive production scale means more consistent supply. ByHeart, as a smaller producer, may have occasional stock issues. Having a backup formula your baby has tried is smart with any DTC brand.
WIC: Similac is WIC-eligible in many states. ByHeart is not. If you receive WIC benefits, Similac is likely the practical choice.
When to Talk to Your Pediatrician
Switching between ByHeart and Similac does not require a doctor's visit for most healthy babies. Contact your pediatrician if your baby shows signs of intolerance.
Signs to Discuss With Your Pediatrician
- Your baby is consistently refusing feeds or eating significantly less than expected
- Persistent vomiting (not just spit-up) after most feedings
- Blood or mucus in stools
- Significant fussiness that does not improve after 1–2 weeks on a new formula
- Poor weight gain or weight loss
- Signs of allergic reaction: hives, facial swelling, wheezing, or difficulty breathing (seek immediate care)
Most formula discomfort (mild gas, occasional spit-up) is normal. Give any new formula at least 1–2 weeks before deciding it is not working.
The Bottom Line
ByHeart offers genuine formulation innovation at a significant premium. Similac offers a proven formula with broad availability at roughly half the price. Neither is clearly superior for healthy babies.
Choose ByHeart if: you value whole-protein formulation and lactoferrin, the $250–300/month cost is comfortable, and limited retail availability is manageable.
Choose Similac if: you want broad availability, HMO prebiotic addition, a lower price point, or access to Similac's full range of specialty formulas.
Either works well if: your baby is healthy and full-term. Both are nutritionally complete and FDA-compliant.
If you are switching, tracking feeds and symptoms for 1–2 weeks gives you real data. tinylog logs everything so you can see whether the switch made a difference.
For more, see ByHeart vs. Enfamil, Bobbie vs. ByHeart, and Enfamil vs. Similac.
Related Guides
- Best Baby Formulas 2026 — An evidence-based guide
- ByHeart vs. Enfamil — Is the premium price worth it
- Enfamil vs. Similac — A complete comparison
Sources
- U.S. Food and Drug Administration. "21 CFR Part 107 — Infant Formula." Code of Federal Regulations.
- American Academy of Pediatrics. "Choosing an Infant Formula." HealthyChildren.org, 2024.
- Manzoni P, et al. "Bovine lactoferrin supplementation for prevention of late-onset sepsis in very low-birth-weight neonates." JAMA, 2009.
- Marriage BJ, et al. "Infants fed a lower calorie formula with 2'-FL show growth and 2'-FL uptake similar to breastfed infants." Journal of Pediatric Gastroenterology and Nutrition, 2015.
- U.S. FDA. "Infant Formula Guidance Documents and Regulatory Information." fda.gov, 2023.
This guide is for informational purposes only and is not a substitute for professional medical advice. Formula recommendations should be discussed with your pediatrician, especially for babies with allergies, reflux, or other medical conditions.